Task Manager Programming Guide

Task Manager Programming Guide
TB8100 base station
Task Manager
Programming Guide
Application Note TN-1154-AN
26 April 2007
Contents
1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Creating Task Manager Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.3 Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.4 Timers, Counters, and Flags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2
How Task Manager works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1 Overruns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.2 Transition Into and Out of Run mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3
Tips For Programming Task Manager Tasks . . . . . . . . . . . . . . . . . . . . . . . . 15
3.1 Laying Out Your Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.2 Enhancements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4
Simple Task Manager Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.1 Responding to a Digital Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.2 Setting a Digital Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.3 Controlling the Auxiliary Power Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.4 Keying the Transmitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.5 Notifying Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.6 Notifying Major Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.7 Notifying External Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.8 Notifying Alarms from a Linking Transceiver . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.9 Disabling a Configured Function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.10 Changing Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.11 Selecting Profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.12 Remote Control Using a Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5
Task Manager Application Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.1 Repeater Changeover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.2 Data and Speech Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.3 Base Station with Automatic Charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5.4 Base Station that Controls Landing Lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
5.5 Scanning Repeater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
5.6 Improvements to Alarm Center Dial-Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
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6
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
7
Testing and Debugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
8
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Associated Documentation
TB8100 Service Kit User’s Manual (MBA-00010-xx) and online Help.
TN-947-AN TB8100 Base Station Computer Controlled Interface Protocol
1
Introduction
This technical note aims to give guidance to system integrators who need to
make use of Task Manager’s more advanced capabilities. It complements the
Service Kit online Help and manual, which provide detailed information on
Service Kit forms and on individual Task Manager inputs and actions.
Task Manager is a powerful processing engine that adds intelligence to each
base station, enhancing its flexibility and configurability. As part of the
firmware running on the reciter’s digital board, Task Manager is able to
respond to various inputs or operating parameters. Task Manager monitors
a wide range of base station parameters. If one of them changes, Task
Manager can take appropriate action, for example by changing channel,
setting the digital output, or disabling a configured function. What action (if
any) Task Manager takes depends on the tasks it has been given. Using the
Service Kit, you are able to define these tasks.
TB8100 base stations are fully functional without any Task Manager tasks.
Many base stations do not need a single Task Manager task. Others may need
a few tasks to carry out simple functions such as sending a regular alarm log
to the Alarm Center or using the digital inputs and outputs. In a standard
base station, Task Manager is able to process up to 20 tasks. For more
complex applications such as scanning, the ‘Advanced Profiles and Task
Manager’ license (TBAS020) is required. This makes it possible for Task
Manager to process up to 200 tasks.
External computer equipment can carry out similar functions to Task
Manager. Using the proprietary Tait computer-controlled interface (CCI)
protocol, it can read the state of base station parameters and instruct the base
station to carry out any of the actions that Task Manager can. For more
details, see TN-947-AN.
Tasks are statements in a very simple programming language. Tasks say what
action is to be carried out when a monitored parameter changes. All tasks
have one of two forms:
IF <input>, THEN <action>
IF NOT <input> THEN <action>.
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For example:
IF Receiving valid signal THEN Activate digital output 1.
IF NOT Receiving valid signal THEN Deactivate digital output 1.
This example code works as follows. Task Manager continually monitors the
receiver gate, along with many other base station parameters. When the
receiver unmutes, the input ‘receiving valid signal’ becomes true. When
Task Manager next processes its tasks, it executes the first task, which results
in the action of activating digital output 1.
Similarly, when the call ends, the receiver gate mutes. The condition ‘IF
NOT receiving valid signal’ becomes true. When Task Manager next
processes its tasks, it executes the second task, which deactivates digital
output 1.
This simple code example shows how Task Manager can use a digital output
pin to tell external equipment whether the receiver is unmuted.
Task Manager only operates when the base station is in Run mode. The
Service Kit does not need to be connected for the tasks to be performed.
1.1
Creating Task Manager Tasks
To change the way Task Manager works, you add and modify tasks using the
Service Kit, and then you program the changes into the base station. In
effect, you are creating scripts that make the base station perform simple
actions. This customizes the way the base station operates without
modifying its firmware. Figure 1 shows an example Task Manager form
with its list of tasks. To create a task, you select an input and an action, each
from a drop-down list, and then insert it into one of the folders or subfolders
in the task list. Comments function as headings under which tasks are
grouped. For more details on working with this form, see the Service Kit
manual or online Help. Help buttons alongside the input and action boxes
provide context-sensitive Help for the particular input or action that you
have selected.
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Figure 1
Task Manager form
Selected input
1.2
Help
Selected action
Help
Inputs
Task Manager inputs are binary in nature. They can only have two states: on
or off, enabled or disabled, set or cleared. Inputs are of two main types,
‘basic’ and ‘override.’ For a list of all inputs, see Table 1 on page 13.
Basic inputs
Basic inputs come from various parts of the base station. They include all
alarms. At the beginning of the processing cycle (see “How Task Manager
works” on page 9), basic inputs are latched; their state cannot change until
the current processing cycle is completed.
Override inputs
Override inputs can only become true through a Task Manager override
action. They are internal to Task Manager. When an override action occurs,
the change is immediately available and can affect the processing of
subsequent tasks in the list.
Other inputs
For counters, timers and flags, see “Timers, Counters, and Flags” on page 8.
The state of each digital output is also available as an input to Task Manager.
For custom inputs, see “Custom inputs” on page 17.
Input Menus
Figure 2 gives an overview of the drop-down menus that allow you to select
an input. The main menu contains general items and the submenus group
inputs that relate to Alarms, signalling profiles, channel profiles, and system
I/O.
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Figure 2
1.3
Input menus
Actions
Task Manager actions are similarly binary in nature. They can turn a digital
output on or off, set or clear a flag, enable or disable a function. They trigger
an action but cannot provide any parameters that configure that action.
Actions are of two main types, ‘override’ and ‘do now’. These actions have
different effects.
Override actions
Override actions enable, disable, or toggle a configured base station
function. As most of these functions are enabled by default, the main use of
override actions is to let you turn off a function such as talk through
repeater, power saving, or even the receiver as a whole.
Override actions work by changing the state of a system flag, which is a
particular kind of Task Manager variable. System flags can only be changed
by an override action. Their status is made available at the end of the
processing cycle to other software processes, influencing their logic. The
status of system flags is displayed in Monitor > Base Station > System Flags.
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Each override action has a corresponding system flag. When an override
action is carried out (for example Enable power saving), it ‘enables’
(turns on) the equivalent system flag (in this case, the ‘Power save’ system
flag). Enabling this flag makes the equivalent override input (in this case,
Power saving enabled) become true. Any tasks with that input will be
processed.
‘Do Now’ actions
‘Do now’ actions are carried out immediately after the task is processed.
Task Manager does not wait until the end of the processing cycle before
making the action available externally. If another ‘do now’ action is
processed while the first is still being carried out, it has no effect. If, for
example, a task list has two tasks with the action Send CWID now, and
both are executed, only one CWID will be sent.
Other actions
There are actions based on the state of counters, timers and flags, see
“Timers, Counters, and Flags” on page 8. There are also custom actions,
see “Custom actions” on page 18. Channel actions and digital output
actions do not behave quite like override or like do now actions. The result
of these actions is immediately available internally to Task Manager, but is
only made available externally at the end of the processing cycle. Consider,
for example, a task list with the following:
IF Input A THEN Go to channel 5
IF Input A THEN Make current channel the default
IF Input B THEN Go to channel 6
The first task sets the (internal) channel number to 5. The second task makes
channel 5 the default (even though the base station is still operating
externally on its previous channel). The third task changes the internal
channel number to 6. At the end of the processing cycle, the base station
changes to channel 6. It does not try to change to channel 5.
The situation is similar with digital output actions:
IF Input A THEN Activate digital output 1
If digital output 1 active THEN Send CWID now
If Input B Then Deactivate digital output 1
In this example, the CWID will be sent, but digital output 1 will not in fact
be activated.
Action Menus
Figure 3 gives an overview of the drop-down menus that allow you to select
an action. The main menu contains general items and the submenus group
actions that relate to Alarms, signalling profiles, channel profiles, and system
I/O.
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Figure 3
1.4
Action menus
Timers, Counters, and Flags
Timers, counters, and flags enhance Task Manager’s capabilities. Actions can
set them and inputs can read them. They are exclusively internal to Task
Manager and can only affect the state of Task Manager inputs.
Task Manager monitors their state and can trigger an action if a timer
expires, a counter reaches its maximum, or a flag is set or cleared. The
Service Kit can monitor the current state of all timers, counters, and flags.
Timers
Timers can be considered as a number of 10 ms intervals that must elapse
before the timer reaches its maximum and the input ‘Timer expired’ is
triggered. Tasks can start and stop timers.When a timer is started, it returns
to the beginning of its timing period. Stopping a timer halts timing, so that
the timer cannot expire and cause any actions.
Timers can be used to add a delay between an event and the desired resulting
action. They can also be used to repeatedly toggle a function on and off, for
example to impose a duty cycle on it. If the on time and the off time are
unequal, two timers are needed.
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A timer can have a maximum value of 0 ms, which means that it expires
instantly.
Short timers may not be accurate. A 10 ms timer will expire at the next 10
ms interval (‘tick’). This could in practice be anywhere between 1 and 10
ms after a task starts the timer, depending on how long Task Manager takes
to process its tasks. However, if there are overruns, it could take significantly
longer than 10 ms. Tait therefore recomments that you avoid short timers
(<50 ms) if the task list has more than 10 enabled tasks.
Counters
Counters cannot go past maximum value or roll over (start again after
reaching the maximum). Actions can increment or decrement them. Only
when they reach the maximum can they trigger actions.
Flags
Tasks can set a flag, and the setting of a flag can be an input to an action.
This is a useful method of making visible a particular status. It is important
to distinguish these flags from system flags. These flags are internal to Task
Manager, can be given a meaningful name, and are available for use in tasks.
They play no role at all until tasks are created that set them or read them.
System flags affect the logic of software processes in the reciter and have fixed
names. They also have a default setting that is re-established on entry into
Run mode.
2
How Task Manager works
Basic description
The basic Task Manager concept is shown in Figure 4. A Task Manager
‘tick’ occurs every 10 milliseconds. At each tick, Task Manager begins
processing the tasks in its task list. First it reads the state of the inputs, then
it processes the tasks in its list, beginning with the first and ending with the
last. If the input of a task has not changed, nothing happens. If the input has
changed, processing the task causes the previous state of an output to be
overwritten. Finally, once the tasks in the list have been processed, Task
Manager carries out the actions by sending instructions to other software
processes running on the base station.
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Figure 4
Task Manager processing cycle
10 ms
tick
Read inputs
Process tasks
Update outputs
Send instructions
Actions triggered by
events
It is important to emphasise that Task Manager only executes an task action
if the task input changes from false to true. In other words, tasks are triggered
by events, not states. Take, for example, the following task:
IF digital input 01 active THEN Increment counter 1.
The counter does not increment by 1 every 10 ms when digital input 1 is
active. It only increments when digital input 1 changes from being inactive
to active.
The situation is similar with inverted inputs, for example:
IF NOT digital input 01 active THEN Increment counter 1.
The counter does not increment by 1 every 10 ms when digital input 1 is
inactive. It only increments when the input part of the task becomes true,
that is, when digital input 1 changes from active to inactive.
Tasks processed in
order
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Task Manager processes its tasks strictly in order. It begins with the first task
in the task list with a changed input and ends with the last. This means that
tasks in the General folder are processed first and tasks in the Alarms folder
last. Statements within profile folders (for example the folder for the default
channel folder) are only processed if that profile is referenced by the current
channel.
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More detailed
description
Figure 5 shows in more detail the way Task Manager operates.
Task Manager monitors external base station parameters and updates
information about their state. This information consists of the basic inputs,
which are most of the inputs into the Task processing engine (there are
system flags, flags, counters, and timers as well). When the 10 ms ‘tick’
occurs, Task Manager starts processing the task list. First it latches the basic
inputs so that they do not change during the processing cycle (if for
example, an alarm occurs during task processing, it will not be processed
until the next processing cycle). Then Task Manager processes the
combinatorial logic of any custom inputs, so as to determine whether the
custom input has changed state. Next it starts going through the task list,
from top to bottom. (An optimisation means that it in fact only processes
tasks with changed inputs.) It executes each task, carrying out the required
action.
Figure 5
Task Manager operation
Task Manager
Task processing
Base
station
parameters
Compute
custom
inputs
Inputs
Do now actions
Actions
Task Manager Variables
Monitoring
Alarms
Rx gate
Carrier
Digital inputs
Run mode
etc
Basic
inputs
flags
timers
counters
System flags
Channel actions
Digital output actions
Enable/disable
‘Do now’ actions are immediately made available to external software
processes. All other actions initially only set Task Manager variables. The
new state of these variables is immediately available internally. Later, when
processing the task list is completed, these new variable states are sent to
external software processes, changing channel, setting digital outputs, or
enabling/disabling their operation.
For example:
IF digital input 01 active THEN Enable power saving
IF Power saving enabled THEN Set flag (1)
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In this case, the first task has the override action of enabling power saving.
This changes a system flag. The new state of the Power saving system flag is
immediately available as a Task Manager input, which happens to be the
input of the very next task on the list. Accordingly, Flag 1 will be set. Only
after the processing of the task list is complete does Task Manager instruct
the base station to enable power saving.
The important point to note is that the input ‘power saving enabled’ became
true, even though Task Manager had not yet issued an instruction to the base
station to enable power saving.
2.1
Overruns
If the inputs to more than about 10 tasks have become true since the last
10 ms tick, Task Manager may be unable to process its task list within 10 ms,
so that overruns occur, as shown in Figure 6. Complex custom inputs may
also add to the time that Task Manager needs. If there is an overrun, Task
Manager skips the processing of the task list but still does the following
essential things. Immediately after each tick it reads the state of digital inputs.
It also makes sure that it advances timers by the required number of 10 ms
ticks once it has finished the previous processing cycle. The result is that
tasks triggered by a timer may occur later than expected. In Figure 6, a timer
that should have expired at tick 5 will not expire till well after tick 6 and will
only be processed after tick 7. Of course, this is only of concern where exact
timing is required.
Figure 6
Task Manager Overruns
Tick 1
10 ms
Tick 2
20 ms
TM Events
b
Tick 3
30 ms
b
CD E
Tick 4
40 ms
b
C
D
TM has
overrun tick 3
Key: b
C
D
E
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Tick 5
50 ms
b
E C
Tick 6
60 ms
b
C
Because it
overran, TM does
not process tick 3
Tick 7
70 ms
b
D
b
E CC
TM has
overrun ticks
5&6
C D
E
Because it overran,
TM does not
process ticks 5 & 6
Reading digital inputs
Advancing timers by 10ms
Processing tasks
Updating outputs and performing actions
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2.2
Transition Into and Out of Run mode
When the base station goes into Run mode, Task Manager starts operating.
The input ‘Base station in Run mode’ becomes true and any tasks with that
input are processed. In addition, other tasks are processed. This happens
because Task Manager sets the previous state flag of all tasks to ‘unknown,’
so that Task Manager sees a transition from ‘unknown’ to the default setting,
which can be false or true. So, for example, tasks with ‘IF receiver enabled’
as an input will be processed, because Task Manager sees a transition from
‘unknown’ to ‘true.’ However, tasks with ‘IF NOT receiver enabled’ will not
be processed.
The transition to Run mode also sets all system flags to their defaults. If, for
example, a Task Manager override has disabled subaudible decoding, and
then the base station goes out of and back into Run mode, subaudible
decoding will be re-enabled (most system flags are enabled by default).
Table 1 lists all Task Manager inputs, indicating whether they are ‘external’
(basic) or ‘internal’ (a system flag, counter, timer or flag) and displaying the
default settings of internal inputs.
When the base station goes out of Run mode into Standby mode, Task
Manager stops operating. Task Manager variables (for example the system
flags) are frozen but can be read by other processes. However, in a recent
optimisation (version 3.00), Task Manager does carry out one processing
cycle after the base station goes into Standby mode. This makes it possible
for it to process tasks with the input ‘IF NOT base station in Run mode,’
for example to set a digital output while in Standby mode:
IF NOT Base station in Run mode THEN Activate digital output 1
IF Base station in Run mode THEN Deactivate digital output 1
Table 1
Task Manager inputs
Classification
General
Input
Type
Default
Another receiver in rack
External
n/a
Auxiliary Supply Enabled
Internal
Disabled
Base station in run mode
External
n/a
Counter at maximum (ident)
Internal
0
External channel select enabled
Internal
Enabled
Flag set (ident)
Internal
n/a
Power saving enabled
Internal
Enabled
Syslog service enabled
Internal
Enabled
Timer expired (ident)
Internal
0
Tx relay enabled
Internal
Enabled
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Table 1
Task Manager inputs (Continued)
Classification
Alarms
Channel Profile
Signalling Profile
System I/O
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Input
Type
Default
(all alarms)
External
n/a
Over the air alarm on
Internal
Disabled
Over the line alarm on
Internal
Disabled
CWID enabled
Internal
Enabled
External Tx Key input enabled
Internal
Enabled
Intercom enabled
Internal
Enabled
Line controlled base enabled
Internal
Enabled
Loopback enabled
Internal
Disabled
PA carrier present
External
n/a
PA keyed by Tx Key line
External
n/a
PA keyed by valid Rx
External
n/a
Receiver enabled
Internal
Enabled
Receiving valid signal
External
n/a
Rx Gate line active
External
n/a
Talk through repeated enabled
Internal
Enabled
Transmitter enabled
Internal
Enabled
Transmit power overridden
Internal
Disabled
Subtone decoding enabled
Internal
Enabled
Subtone encoding enabled
Internal
Enabled
Tone 01 detected – Tone 16 detected External
n/a
Balanced input low
External
n/a
Digital Input 01 active – Digital Input External
16 active
n/a
Digital Output 01 active – Digital
Output 08 active
Internal
Deactivated
RSSI high
External
n/a
RSSI low
External
n/a
Unbalanced input low
External
n/a
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3
Tips For Programming Task Manager Tasks
Pay attention to the following when you create sets of Task Manager tasks:
Important
Do not create the task:
IF Base station in Run mode THEN Reset base
station
This results in an inoperable base station. Be careful with
any tasks using powerful actions such as Reset base
station.
Create tasks for
events, not states
Make sure that your thinking is oriented to events and not states when you
create tasks. Tasks are triggered by events. An action only occurs if the input
changes from false to true.
Inverses are always
available
It may appear that there is no suitable input for a task, when the inverse of
an input fits exactly. For example, there is no input ‘Balanced input receiving
signal,’ but you can use ‘IF NOT balanced input low,’ and configure the
threshold between not receiving a signal and receiving one in the Thresholds
form.
Tasks often need to
be in pairs
When you create a task to carry out an action, you often need to create an
opposite task to reverse that action.
IF digital input 1 active THEN disable subaudible encoding
IF NOT digital input 1 active THEN enable subaudible coding
If you only have the first task, subaudible signalling would be disabled the
first time digital input 1 goes active and would continue to be disabled
indefinitely, even if digital input 1 is turned on and off.
IF receiving valid signal THEN start timer 1
IF NOT receiving valid signal THEN stop timer 1
Do now actions, on the other hand, are usually standalone:
IF Tone 2 detected THEN Reset base station
Order can be
important
If a task changes a system flag, a counter, a timer, or a flag, the new state is
available immediately. Other Task Manager variables are also available
immediately. Other task actions do not cause a change until Task Manager
performs its actions at the end of the processing cycle.
A task that uses a system flag, a counter, or a flag as an input will be processed
in the current processing cycle if it comes after the action that sets it but not
if it comes before.
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For example, in the following pair of tasks, making the digital line active
causes a counter to reach its maximum, which in turn enables loopback:
IF Digital input 1 active THEN Increment counter 1
IF Counter at maximum (counter 1) THEN Enable loopback
If the order of these two tasks was reversed, loopback would be not be
enabled in the same 10 ms processing cycle. However, the next processing
cycle would register that the counter had reached its maximum and the task
would be processed.
You probably need
tasks for the
initialisation
process
Your Task Manager code needs to be able to handle power outages and
transitions to Standby mode and back to Run mode, as well as the initial
start-up. The Task Manager input Base station in Run mode can be used
for any tasks you need to carry out the initialisation process. A power outage
results in a return to default settings, not to the settings that Task Manager
has established during its operation. Check that the default settings of system
flags and the inputs derived from them are as you want (see Table 1 on
page 13). For example if you want the talk-through repeater function to be
normally disabled, you need a task to change the start-up default:
IF Base station in Run mode THEN Disable talk through
repeater
In trunking systems, you can enable auxiliary power in Run mode, but
disable it in Standby mode:
IF Base station in Run mode THEN Enable auxiliary supply
IF NOT Base station in Run mode THEN Disable auxiliary supply
This turns off the trunking equipment when you take the base station out
of service.
3.1
Laying Out Your Code
Folders
Tasks must be inserted into one of the available folders. It is not necessary to
put an alarm task in the Alarms folder or a General task in the General
folder. Occasionally, you may want to put a general task in the Alarms folder
to ensure that it is processed at the end of the processing cycle.
You cannot put a task in the top-level Channel Profiles or Signalling Profiles
folder, these can only contain folders for each defined profile. Tasks in a
profile folder are only processed if the current channel uses that profile.
Using comments
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Comments are used as titles for the tasks indented underneath them. The
title should describe the purpose or the function of the group of tasks. This
will help future maintainers.
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Using indenting
Indenting a task assigns it to the comment above. Indenting a comment lets
you create a subheading for the tasks that follow.
Hiding code
Folders and comments have a little box alongside that displays a + or a -.
Click on the box to display or hide the item’s subfolders or assigned tasks.
Hiding items stops the screen getting too cluttered.
Disabling tasks
You can disable tasks in the task list that you do not want to be processed.
This lets you, for example, maintain a common task list for all base stations
in the system, as part of a master configuration file. Simply disable the tasks
not applicable to each particular base station.
3.2
Enhancements
Task Manager has a number of additional features that help to increase the
power of its task statements.
Profile Folders
Putting Task Manager tasks in a profile folder means that they are only
available if the current channel uses that profile. This means that it is possible
to set up a base station to switch between two (or more) sets of Task Manager
tasks. Set up two channels with the same frequency information, but assign
different channel profiles. Place different sets of Task Manager tasks into the
different profiles. Then set up General Task Manager tasks to switch
between channels. For example:
IF Tone 1 detected THEN Go to channel Repeater
IF Tone 2 detected THEN Go to channel LineCtrl
Where Repeater and LineCtrl are the names of two channels in the channel
table.
Using the channel profiles in this way can save you from having to use lots
of combinational logic. However, it does take ~300 ms to change channel.
During this time, tasks that run in profile folders are not available.
Custom inputs
You cannot create entirely new inputs, but you can combine a number of
existing inputs to form a custom input. You select the inputs and specify the
combinational logic that will be used to make the custom input true or false
when the states of the various inputs are combined. For example, you might
create a custom input using a number of minor alarms that will trigger
sending a status message to the Alarm Center.
Custom inputs are specified as a logic tree as shown below. Evaluation is
done from left to right.
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The above custom input is evaluated in this way. First,Counter at
maximum (1) is OR'ed with External reference absent and then
Unbalanced input low is XOR'ed with Digital input 01 active.
Finally, the results of those two operations is AND'ed.
Custom inputs are not allowed directly in other custom inputs. One way
around this is for the custom input to set and clear a flag. This makes it
possible to combine more than eight items in a custom input. For example:
Custom input 1 combines eight alarms
Custom input 2 combines another four alarms
When custom input 1 becomes true, it sets Flag 1
When custom input 2 becomes true, it sets Flag 2.
Custom input 3 combines Flag 1 and Flag 2.
Note
Custom actions
You cannot export and import custom inputs and custom actions.
If the Task Manager code uses these input and action types intensively in a system with many base stations, Tait recommends that
you save the whole configuration file and use it as the basis of new
configurations for the other base stations.
You can combine a number of actions into a custom action. This can
simplify the code.
For example, you could set up custom actions for enabling and disabling
CTCSS. Each custom action contains all of the actions required to enable or
disable the function.
The ‘Enable CTCSS’ custom action consists of:
Enable subaudible decoding
Enable subaudible encoding
Set flag (CTCSS_Active)
The ‘Disable CTCSS’ custom action consists of:
Disable subaudible decoding
Disable subaudible encoding
Clear flag (CTCSS_Active)
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With these custom actions, you only need two tasks to use a digital input to
enable and disable CTCSS:
IF digital input (02) active THEN Enable CTCSS
IF NOT digital input (02) active THEN Disable CTCSS
Custom alarms
4
Task Manager has 16 custom alarms and it can raise or clear these alarms, for
example in response to the activation of a digital input. Custom alarms make
it possible for the base station to notify a syslog collector or the alarm center
that an external alarm has been triggered.
Simple Task Manager Functions
The following section gives some example Task Manager code fragments.
These let you carry out simple functions. They can also serve as building
blocks in more complex applications.
4.1
Responding to a Digital Input
Digital inputs have no built-in function; you construct tasks that determine
the base station’s response to their activation or deactivation. Here are some
suggestions.
Subtone Decode
Disable Pin
When digital input # is active, the base station disables the decoding of
subaudible signalling.
IF Digital input # active THEN Disable subaudible decoding
IF NOT Digital input # active THEN Enable subaudible decoding
Cancel Alarms Pin
When the digital input is activated, Task Manager action ceases to dial up an
Alarm Center to send alarm logs and status messages.
IF Digital input # active THEN Disable alarm service
IF NOT Digital input # active THEN Enable alarm service
External alarm
response
If the digital input is wired to (for example) the site facility’s door alarm, the
dispatcher can be alerted to the triggering of this alarm.
IF Digital input # active THEN Start over the line alarm
IF NOT Digital input # active THEN Stop over the line alarm
4.2
Setting a Digital Output
Digital outputs also have no built-in function in the base station; they are
under the control of Task Manager so that you can determine their function.
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4.3
Controlling the Auxiliary Power Output
In the default configuration setting, the auxiliary power output at the rear
of the PMU is automatically turned on when mains power is on. Task
Manager is not involved. However, you can configure the auxiliary power
output to be under the control of Task Manager (Configure > Base Station
> Miscellaneous). This is the only way to turn the auxiliary power output
on, if the base station only uses DC power.
1.
Select Configure > Base Station > Miscellaneous.
2.
In the Auxiliary power control list, select Task Manager.
3.
Create a Task Manager task such as the following:
IF Base station in Run mode THEN Enable auxiliary supply
4.
If you want the auxiliary power supply to be turned off when the base
station is in Standby mode, add the following task:
IF NOT Base station in Run mode THEN Disable auxiliary supply
The following flowchart shows the conditions under which auxiliary power
is on or off when the base station is in Run mode.
Start
N
Submodule
present
No auxiliary
power
Y
Config:
Auxiliary power
control
Mains
Task
Manager
Turn auxiliary
power off
Disable
TM action:
Aux. supply
PMU
power
source
DC
Auxiliary
power is off
AC
Auxiliary power
is on
Enable
Turn auxiliary
power on
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4.4
Keying the Transmitter
Task Manager can key or unkey the transmitter. The effect is exactly the
same as if the Tx Key line were activated or de-activated.
For example:
IF Digital input # active THEN Enable TM Tx Key
IF NOT Digital input # active THEN Disable TM Tx Key
Disabling the Task Manager Tx Key does not override the signal on the Tx
Key line. The following flowchart shows the conditions under which the PA
is keyed.
Start
Inactive
External Tx
Key line
Active
TM action:
External
Tx Key
Disabled
Enabled
Key
transmitter
TM action:
TM Tx Key
Disable
No action
or
unkey transmitter
Enable
Key
transmitter
4.5
Notifying Alarms
Alarms are notified only by Task Manager action. These actions can be
triggered at regular intervals, using a timer, and/or in response to alarms
(Base station alarm on for any alarm, a custom input for up to eight
alarms.)
Note
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Disabling an alarm does not stop it triggering a Task Manager
action. To stop an alarm triggering an action, disable the task itself.
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Enabling Email/
Alarm Log
If your system has an Alarm Center, Task Manager action can send the alarm
log (Send alarm log now) or send the alarm log together with the status
of all alarm parameters (Email status now). Tasks can do this at regular
intervals (for example, once a week) and/or in response to an alarm.
IF Base station in Run mode THEN Start timer (1 week timer)
IF Timer expired (1 week timer) THEN Email status now
IF Timer expired (1 week timer) THEN Start timer (1 week timer)
Note that the base station has a configurable minimum interval between one
sending of the alarm log or status message and another, to prevent flooding
the Alarm Center with calls.
Suppose, for example, the minimum interval is 30 minutes, and the
following task is set up:
IF Reverse power high THEN Email status now
If the reverse power alarm is triggered, the base station will dial out to the
Alarm Center and send its alarm log and status message. If the fault is
intermittent and the alarm continues to go on and off, the base station will
not dial out again until 30 minutes after the previous dial-out. It will then
send the alarm log and status as they currently are, not as they were when
the alarm was triggered for a second time. In other words, items for sending
to the Alarm Center are not queued.
Enabling over-theair or over-the-line
pips
Alarms can also be notified by sending pips over the air or down the line.
Temporarily
cancelling alarm
logging
It may be useful to be able to temporarily stop sending alarms to the Alarm
Center, for example if testing or commissioning is generating frequent
alarms.
IF Base station alarm on THEN Start over the air alarm
IF NOT Base station alarm on THEN Stop over the line alarm
IF Tone 02 detected THEN Disable email service
IF Tone 03 detected THEN Enable email service
4.6
Notifying Major Alarms
By creating a custom input, you can set up Task Manager to notify an alarm
only if that alarm is important. (In a similar manner Task Manager can take
a different action if a relatively unimportant alarm occurs.)
First define a custom input that includes all the alarms that are important for
the application, for example:
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Then create a pair of Task Manager tasks using the custom input and
providing an appropriate notification method, for example:
IF Major alarm THEN Activate digital output 1
IF NOT Major alarm THEN Deactivate digital output 1
4.7
Notifying External Alarms
External equipment at the site such as a door alarm or an air conditioner can
generate alarms that activate a base station digital input. To notify this alarm
to the alarm center or syslog collector or to record the event in the alarm
log, you need to use a custom alarm.
IF Digital input 01 active THEN Raise custom alarm (door open)
IF Digital input 01 active THEN Email status now
IF NOT Digital input 01 active THEN Clear custom alarm (door
open)
(The custom alarm has been renamed ‘door open’ from the default name
‘Custom Alarm 1’).
As clearing an alarm does not create an entry in the fault log, you may want
to create an additional alarm that is triggered when the door is closed.
IF NOT Digital input 01 active THEN Raise custom alarm (door
closed)
IF NOT Digital input 01 active THEN Email status now
IF Digital input 01 active THEN Clear custom alarm (door closed)
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Note
4.8
When custom alarms are notified to an alarm center, they appear
in the fault log of the email message but not in the list of current
alarms.
Notifying Alarms from a Linking Transceiver
The remote transceiver in an RF link often does not have a line connection,
and so cannot directly notify any alarm to the alarm center or syslog
collector. However, Task Manager can be used to provide indirect
notification via the RF link to the local base station and from there to the
alarm center or syslog collector.
In the remote transceiver, Task Manager changes channel or signalling
profile when an alarm is triggered so that different subaudible signalling is
transmitted. The local base station detects the new signalling, which triggers
a Task Manager action to raise a custom alarm. For this, an Advanced
Profiles and Task Manager licence is required.
Remote Transceiver
Tasks
When the remote transceiver has an alarm, it changes to a channel with
different subaudible signalling.
IF Base station alarm on THEN Go to channel Channel 002
IF NOT Base station alarm on THEN Go to channel Channel 001
(Alternatively, you could enable Task Manager selection of signalling profiles
and Task Manager could change signalling profile instead of changing
channel. This may be preferable if there are other reasons for changing
channel.)
Note
Local Base Station
Tasks
In practice, it will be better to create a custom input that combines
major alarms, so that unimportant alarms do not result in a notification.
When the local base station detects the different subaudible signalling, it
raises the alarm.
IF Tone 02 detected THEN Raise custom alarm (remote link
alarm)
IF NOT Tone 02 detected THEN Clear custom alarm (remote link
alarm)
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4.9
Disabling a Configured Function
Task Manager can disable a number of configured base station functions. It
does this by changing the state of the relevant system flag. The Service Kit
displays all system flags (Monitor > Task Manager > System Flags).
For example:
IF Digital input 03 active THEN Disable talk through repeater
IF NOT Digital input 03 active THEN Enable talk through
repeater
4.10
Changing Channel
The current operating channel is generally selected by the configuration (set
the default channel in Configure > Base Station > General) or by hardware
(you switch digital inputs after enabling and configuring hardware channel
selection in Configure > Base Station > System Interface).
Task Manager offers additional methods for selecting the current operating
channel. If the base station has an Advanced Profiles and Task Manager
feature license, these methods can be used to change any channel setting.
Simply create channels and profiles with the configurations desired and use
Task Manager tasks to change from one to another.
Make sure that your Task Manager code gives the expected result after
power outages and transitions out of and back into Run mode.
Selecting a different
channel
Task Manager has actions that can select a different channel from that
specified by the configuration: Go to channel nn and Go to next
channel.
IF Tone 03 detected THEN Go to channel Channel 004
IF Tone 04 detected THEN Go to channel Channel 003
These actions do not work if hardware channel selection is enabled.
Shifting channel
selection between
hardware and
configuration
Task Manager can shift the control of channel selection between the digital
inputs and the configuration. You must have enabled and configured
hardware channel selection and selected a default channel using the Service
Kit.
Task Manager controls the system flag H/W channel select. This flag is
enabled by default, which means that hardware channel selection will work.
If you disable this flag, control of channel selection reverts to software, and
the channel configured as the default becomes the current operating
channel.
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IF Tone 03 detected THEN Disable external channel select
IF Tone 04 detected THEN Enable external channel select
Tip
Shifting channel
selection between
Task Manager and
hardware
Alternatively, use the digital inputs to instruct the base station to
use the software-selected channel. Simply set the digital inputs to
select channel number 000.
Task Manager change channel actions override the default channel selected
by the configuration, but they do not override hardware channel selection.
If hardware channel selection is enabled, the base station continues to
operate on the channel selected by hardware, even if Task Manager processes
a change channel action. However, the Task Manager action does change
the internal ‘software channel number.’ If hardware channel selection is
subsequently disabled, the base station will change to the channel specified
by the latest Task Manager action.
For example
IF Base station in Run mode THEN Go to channel Channel 002
IF Base station in Run mode THEN Start timer (Timer 01)
IF Timer (Timer 01) expired THEN Disable external channel
select
In this example, the base station will operate initially using the channel
defined by the digital inputs, for example Channel 001, even though Task
Manager has selected Channel 002. The base station does remember
Channel 002 as its ‘software channel number.’ Once the timer expires, Task
Manager disables hardware channel selection and the base station changes to
Channel 002.
Changing the
default channel
You can use Task Manager to change the default channel. This is the
equivalent of changing the configuration. The new default channel appears
in the General form (Configure > Base Station > General).
Monitoring the
current channel
For all the above channel selection methods, the Channel form (Monitor >
Monitoring > Channel) displays the channel currently in use.
4.11
Selecting Profiles
Generally, the base station uses the channel profile and the signalling profile
that are assigned to the current operating channel. However, Task Manager
can override the channel table’s selection of channel and/or signalling
profiles and then its own tasks select the profiles used. This gives greater
flexibility in the assigning of profiles and a greater number of combinations
of assigned profiles and other channel settings.
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The following flowchart shows how profiles are selected.
Start
TM action:
TM channel profile
selection
Disabled
Channel table
selects profile
Enabled
TM action:
Select channel
profile n
No
Default channel
profile is used
Yes
Channel
profile n is
used
Enabling Task
Manager selection
of profiles
The system flags TM signalling profile and TM channel profile are disabled
by default. When they are disabled, the base station uses the profiles assigned
to the current operating channel.
When these system flags are enabled, control of profile selection is passed to
Task Manager. If Task Manager does not select a profile, the base station uses
the default profile. If a Task Manager task selects a profile, the base station
uses that profile.
Disabling the Task Manager selection of profiles can be used to pass the
control of profiles back to the channel table. If a Task Manager task selects a
profile, the base station ‘remembers’ that profile, and if control subsequently
passes back to Task Manager, that profile will be used.
Selecting channel
profiles
Here is an example set of Task Manager tasks:
IF Base station in Run mode THEN Enable TM channel profile
selection
IF Digital input 01 active THEN Select channel profile (Ch prof 2)
IF Digital input 02 active THEN Select channel profile (Ch prof 3)
Selecting signaling
profiles
Here is an example set of Task Manager tasks:
IF Base station in Run mode THEN Enable TM signalling profile selection
IF Digital input 03 active THEN Select signalling profile (Sig prof 2)
IF Digital input 04 active THEN Select signalling profile (Sig prof 3)
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Monitoring profiles
4.12
You can monitor the base station and see which profiles it is currently using.
The Channel form (Monitor > Monitoring > Channel) displays the profiles
currently in use, even if they are selected by Task Manager, not the current
channel. You cannot tell from this form whether Task Manager has selected
the profile, but you can select Monitor > Task Manager > System Flags. If
the TM signalling profile or the TM channel profile flag is enabled, Task
Manager has selected the corresponding profile.
Remote Control Using a Radio
If the base station has an Advanced Profiles and Task Manager feature
license, you can program radio to transmit using different subaudible
signaling and use each CTCSS tone or DCS code to carry out a different
action.
The following example controls the talk through repeater function:
IF Tone 02 detected THEN Disable talk through repeater
IF Tone 03 detected THEN Enable talk through repeater
5
Task Manager Application Examples
Task Manager makes it possible for you to build complex functions into the
base station. Here are some examples of to give you an idea of what can be
done.
Important
5.1
While Tait has carefully tested Task Manager, no guarantee
can be given that these examples will work correctly for
your system. Make sure that you thoroughly test any set of
Task Manager tasks before commissioning the system.
Repeater Changeover
A line-controlled base station is connected to a console that provides tone
on idle. The following Task Manager tasks automatically convert the
TB8100 to a talk-through repeater if the line fails. When the line is reestablished, the TB8100 reverts to line-controlled operation.
IF Base station in Run mode THEN Disable talk through
repeater
This disables the base station’s talk through repeater mode whenever it enters
Run mode.
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IF Balanced input low THEN Enable talk through repeater
IF Balanced input low THEN Disable line-controlled base
station
IF Balanced input low THEN Start over the air alarm
If the line fails, the input line level falls below the prescribed minimum. This
triggers Task Manager actions that switch off the line-controlled base station
mode, enable the talk through repeater mode, and start sending alarm pips
over the air.
IF NOT Balanced input low THEN Disable talk through repeater
IF NOT Balanced input low THEN Enable line-controlled base
station
IF NOT Balanced input low THEN Stop over the air alarm
When the line is re-established, Task Manager actions re-establish the linecontrolled base station function and stop the alarm.
5.2
Data and Speech Service
A repeater needs to relay speech as well as data. The speech needs to be preemphasised while the data needs the full band from < 50 Hz to 3000 Hz.
Speech is sent with a CTCSS tone.
The base station needs to be able to automatically change between repeating
pre-emphasised audio and repeating full band audio.
To achieve this, follow these steps:
1.
Set up Channel 1 as a speech repeater. The channel profile (Signal
Path tab) is set to De-emph Speech Band / Pre-emph Speech Band.
2.
Set up Channel 2 as a data repeater. The channel profile (Signal Path
tab) is set to Flat Full Band.
3.
Set Timer 1 to 150 milliseconds, corresponding to the time that the
base station needs to decode subaudible signalling.
4.
Create two custom inputs:
Data Chan Detected, which consists of Timer 1 expired AND
Tone 1 NOT detected.
Speech Chan Detected, which consists of Timer 1 expired AND
Tone 1 detected.
5.
Create the following Task Manager tasks for Channel 1:
IF Receiving valid signal THEN Start timer 1
IF NOT Receiving valid signal THEN Stop timer 1
IF Data Chan Detected THEN Go to channel 002
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Receiving a valid signal on Channel 1 starts a timer. If no subaudible
signalling is detected when the timer expires, the custom input Data
Channel Detected becomes true and Task Manager instructs the base station
to go to channel 002.
6.
Create the following Task Manager tasks for Channel 2
IF Receiving valid signal THEN Start timer 1
IF NOT Receiving valid signal THEN Stop timer 1
IF Speech Chan Detected THEN Go to channel 001
Receiving a valid signal on Channel 2 starts a timer. If subaudible signalling
is detected before the timer expires, the custom input Speech Channel
Detected becomes true and Task Manager instructs the base station to go to
channel 001.
5.3
Base Station with Automatic Charging
If the battery voltage goes low, the base station operates on lower power,
starts the generator and sends transmitter pips. As soon as the battery voltage
is back to normal, transmitter power is increased. The generator continues
for one hour (or until a high battery voltage alarm is triggered). This ensures
that the battery is properly charged.
To set this up, follow these steps:
1.
Set up Channel 1 at 100 watts for mains power and 60 watts for battery power.
2.
Set up Channel 2 as a low battery channel, with only 25 watts output
power.
3.
Set up Timer 1 as Generator On timer with a duration of one hour.
4.
Set up a custom action End of Charging with the following actions:
Deactivate Digital Output 1 AND
Stop timer 1 (Generator On timer)
Stop over the air alarm
5.
Set up the following Task Manager tasks:
IF Battery voltage low THEN Go to channel 002
IF NOT Battery voltage low THEN Go to channel 001
When the battery voltage is low, this switches operation to Channel 002,
which has a reduced PA output power.
IF Battery voltage low THEN Activate Digital Output #1.
IF Battery voltage low THEN Start over the air alarm
IF Battery voltage low THEN Start timer #1.
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When the battery voltage is low, a digital output is set, which starts the
generator. Additional actions turn on over the air pips and start a timer that
will turn the generator off.
IF Battery voltage high THEN End of Charging
IF Timer #1 expired THEN End of Charging
These two tasks stop the generator when the battery voltage gets too high
or when the Generator On time expires.
5.4
Base Station that Controls Landing Lights
A small private airport does not have full time air traffic control. When
landing at night, the pilot needs to switch on the runway lights. Pilots have
VHF radios without CTCSS, Selcall, or any other signalling. The pilot
presses PTT three times within two seconds to switch on the lights.
1.
Wire Digital Output #6 to control the lights.
2.
Give Counter #1 a maximum of 3.
3.
Give Timer #1 a maximum of 2 seconds.
4.
Give Timer #2 a maximum of 30 minutes
5.
Set up the following Task Manager tasks:
IF Receiving valid signal THEN Start timer (Timer 1)
IF Receiving valid signal THEN Increment counter (Counter 1)
IF Timer expired (Timer 1) THEN Reset counter (Counter 1)
This set of tasks detects three presses of PTT, provided they occur
before Timer #1 expires.
IF Counter at maximum (Counter 1) THEN Start timer (Timer 2)
IF Counter at maximum (Counter 1) THEN Activate Digital
Output 6
IF Counter at maximum (Counter 1) THEN Reset counter
(Counter 1)
This set of tasks starts the lights timer, turns the lights on, and re-starts
the counter for detecting three presses of PTT.
IF Timer expired (Timer 2) THEN Deactivate Digital Output 6
This task turns the lights off when the 30 minutes has elapsed.
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5.5
Scanning Repeater
In a two-repeater site, Task Manager makes it possible for either repeater to
turn into a scanning repeater if the other repeater fails. The scanning
repeater handles both channels, providing a complete backup system.
When a repeater fails, the other starts scanning. It changes to a channel, waits
a few 100ms, checks the received signal, and, if nothing is there, it goes to
the next channel. If there is a signal, it will just repeat it as usual, complete
with all the signalling and line output requirements for that channel. Here a
single base station is providing the same service but with a poorer
throughput.
IF Base station in Run mode THEN Start timer (ChangeChannel)
IF Receiving valid signal THEN Stop timer (ChangeChannel)
IF Receiving valid signal THEN Stop timer (On Channel)
IF NOT Receiving valid signal THEN Start timer (On Channel)
IF Timer expired (ChangeChannel) THEN Go to next channel
IF Timer expired (ChangeChannel) THEN Start timer
(ChangeChannel)
IF Timer expired (On Channel) THEN Go to next channel
IF Timer expired (On Channel) THEN Start timer (ChangeChannel)
The channel change time is currently ~300ms. The CTCSS decode time is
~150ms. Hence it takes about 450ms to scan a channel with CTCSS tones.
Tait therefore recommends that you set the ChangeChannel timer to
500ms. The OnChannel timer needs to be long enough to make sure that
the conversation has ended.
This example is a straightforward scanner. It will search through all the
channels in the channel table looking for activity. A small variation on this
can make it stay on its home channel until an external signal triggers the
scanning.
5.6
Improvements to Alarm Center Dial-Out
Task Manager can prevent a base station dialling out to the Alarm Center
when an alarm triggers briefly and is then cleared.
Alarm dial-out only
if alarm continues
for one minute
This example set of tasks ensures that there is an alarm dial-out only if the
alarm is still active when a one-minute timer expires. A flag is used to
prevent the timer being repeatedly restarted if an alarm is chattering.
To set this up, follow these steps:
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1.
Set up the flag Timer running.
2.
Set up the timer Alarm timer with a maximum of 1 minute.
3.
Create the custom input Alarm still on. It consists of:
Timer expired (Alarm timer) AND Base station alarm on
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4.
Create the following tasks in the General folder.
IF Base station alarm on THEN Set flag (Timer running)
IF Flag set (Timer running) THEN Start timer (Alarm timer)
IF Timer expired (Alarm timer) THEN Clear flag (Timer running)
IF Alarm still on THEN Email status now.
Alarm dial-out if
alarm continues for
one minute or is
triggered three
times within a
minute
This example improves on the previous set of tasks by ensuring that there
still is an alarm dial-out if an alarm triggers briefly but repeatedly.
To set this up, follow these steps:
1.
Set up the flag Timer running.
2.
Set up the timer Alarm timer with a maximum of 1 minute.
3.
Set up the counter Alarm counter with a maximum of 3.
4.
Create the custom input Alarm still on. It consists of:
Timer expired (Alarm timer) AND Base station alarm on
5.
Create the custom action Start over. It consists of:
Clear flag (Timer running)
Stop timer (Alarm timer)
Reset counter (Alarm counter)
6.
Create the following tasks in the General folder.
IF Base station alarm on THEN Set flag (Timer running)
IF Base station alarm on THEN Increment counter (Alarm
counter)
IF Flag set (Timer running) THEN Start timer (Alarm timer)
IF Timer expired (Alarm timer) THEN Clear flag (Timer running)
IF Alarm still on THEN Email status now.
IF Counter at maximum (Alarm counter) THEN Email status now
IF Timer expired (Alarm timer) THEN Start over
IF Counter at maximum (Alarm counter) THEN Start over
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6
Specifications
The following are the maximum parameter values and maximum number of
items that Task Manager supports.
Item
7
Maximum
Tasks and comments (lines in task list)
500
Enabled tasks (with Advanced Profiles and Task
Manager feature license)
200
Enabled tasks (without Advanced Profiles and Task
Manager feature license)
20
Custom inputs
20
Custom actions
20
Custom alarms
16
Timers
16
Maximum timer duration
7 days or 168 hours
Counters
16
Counter maximum
200,000
Flags
16
Log of recent actions
40 task actions
Testing and Debugging
Any Task Manager applications you create should be thoroughly tested
before going live. It may be helpful to set up the base station on the bench
with a CTU. This makes it easy to toggle digital inputs, read digital output,
feed noise into the receiver, and so on. The following are some tips to help
you.
Viewing the Log
The Recent Actions form displays the Task Manager log. This displays the
last 40 tasks that were actioned. The log is cleared on entering Run mode.
You may therefore want to save the log to a file before going into Standby
mode or turning the base station off.
Note
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If you modify the base station’s task list, the Service Kit will not
correctly display tasks that were actioned beforehand.
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Checking System
Flag states
The System Flags form displays the current status of all system flags. This
shows you what base station functions Task Manager has disabled or reenabled.
Viewing flags/
counters/timers
There are monitoring forms for flags, counters, and timers. They display the
current status of each group of items.
Optimising Service
Kit display
The Service Kit polls the base station for updates. If the polling interval is
long, you will not see Task Manager changes until well after they have
occurred. You might want to temporarily reduce the polling interval while
you are testing and debugging (Select Tools > Configure Connections,
select the connection and click Edit).
Using flags for
debugging
When debugging, you can add tasks that set or clear flags, and then view the
state of the flag to see if the condition to perform an action is present or not.
For example:
IF Tx Relay enabled THEN Set flag 1
IF NOT Tx Relay enabled THEN Clear flag 1
If you run out of flags, use a counter with a maximum value of ‘1’, or a
digital input that is not present on your system interface.
Shortening timers
When testing timers, you can speed up the evaluation time by reducing
timer durations.
Printing the task list
To print the list of tasks and other Task Manager information, from the
Service Kit select File > Print. Select Base station - Task Manager, and, if
appropriate, other categories such as Task Manager - Custom Actions.
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8
Troubleshooting
If Task Manager is behaving in an unexpected way, check the following list.
Missing a toggled
input
If an external input is toggled twice during a processing cycle, the change
might not be seen. For example, if an input becomes true and then false
again within the processing cycle, tasks with that input may not be
processed. At the beginning of each 10 ms processing cycle, basic inputs are
latched. By the time the next processing cycle processes the task, its input
has become false again.
Outputs only
change once
Actions (setting system flags, setting the channel number, ‘do now’ actions)
are only sent to other external TB8100 software processes at the end of the
processing cycle. This means that tasks can carry out an external action
several times, causing several internal changes, but there will only be a single
external action, at the end of the processing cycle.
Action can trigger
other actions
without ever
becoming visible
itself
External actions have an immediate effect internally. This means that their
new value is immediately available to subsequent tasks in the task list. For
example, an action could disable the receiver system flag, and this could
trigger a second action. If a third action enabled the receiver system flag, the
results of the second action would become visible, but the receiver would
never actually be disabled.
Flag does not clear
when expected
It can happen that a flag does not clear when expected. If the flag is set at
the beginning of the processing cycle, cleared at its end, and then set again
at the beginning of the next cycle, tasks with ‘IF flag n set’ as their input do
not know that the input has changed and so are not processed.
Task in channel
profiles not
actioned until an
external channel
change
Task Manager only processes tasks in profiles that are assigned to the current
channel. If Task Manager changes channel, a change in the profile
assignment only occurs once the channel has actually changed. This takes
about 300 ms. It does not occur as soon as Task Manager has set the new
channel internally.
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Publication Information
Issuing Authority
This TN was issued by:
Distribution Level
Associate.
Publication History
Amendment Record
Publication Date
Kurt Ebrecht
Technical Publications Manager
Author
28 April 2006
I Scott/S McQueen/L Chisholm
15 September 2006
L Chisholm
26 April 2007
L Chisholm
Publication Date
Page
Amendment
28 April 2006
First release
15 September 2006
Expanded 4.6 Changing channel. Added 4.7
Changing Profiles. 5.6 Improvements to Alarm
Center Dial-Out. Warning about some TM tasks.
26 April 2007
Additional TM actions: custom alarms, keying
transmitter, notifying major alarms. Flowcharts for
some simple Task Manager functions.
Tait Contact Information
Corporate Head
Office
New Zealand
Tait Electronics Limited
P.O. Box 1645
Christchurch
New Zealand
For the address and telephone number of regional offices, refer to the
TaitWorld website:
Website: http://www.taitworld.com
Technical Support
For assistance with specific technical issues, contact Technical Support:
E-mail: support@taitworld.com
Website: http://support.taitworld.com
TN-1154-AN
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© Tait Electronics Limited 26 April 2007
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