CONTROLLING THE POWER TO CARD SLOTS
7.1
7.2
7.3
7.4
7
Controlling The Power To Card Slots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Controlling Power Through The Windows Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Controlling Power Through The SDK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Card Slot Control API Elements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
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Chapter 7: Controlling The Power To Card Slots
Controlling The Power To Card Slots
7.1 Controlling The Power To Card Slots
The Mobile Devices SDK provides functions that control the power status of card slots. There are situations,
such as in hospitals or airports, where it is necessary to temporarily prevent radios from transmitting. Using
SDK functions to disable power to the card slot containing the radio achieves this. Most Windows CE-based
Psion Teklogix hand-held, and vehicle-mount, computers have this feature available on all their card slots;
however, there are some exceptions. Refer to the table below for details.
For those card slots that cannot be powered off, the driver for the card slot is unloaded, and all further
attempts by the application to communicate with the card slot are ignored; however, the card slot remains
fully powered, so the outcome depends on the behaviour of the radio card under these circumstances.
The following table lists the Psion Teklogix Windows CE-based computers, their card slots, and whether the
card slots can be controlled by the SDK:
Psion Teklogix
Computer
7530
Card Slot Type
SDK Hardware
Name
Software
Control Of
Power State
Cards Accepted
SD-MMC
SD-MMC
Yes
SD card
MMC card
7535
8525
CF
PCMCIA Slot 0
Yes
CF card
SD-MMC
SD-MMC
(see note 1)
No
SD card
CF
PCMCIA Slot 0
(see note 2)
Yes
CF card
SD-MMC
SD-MMC
Yes
SD card
MMC card
MMC card
CF
PCMCIA Slot 0
Yes
CF card
PCMCIA
PCMCIA Slot 1
Yes
PCMCIA card
CF card in adaptor
8530
SD-MMC
SD-MMC
Yes
SD card
MMC card
CF
PCMCIA Slot 0
Yes
CF card
PCMCIA
PCMCIA Slot 1
Yes
PCMCIA card
CF card in adaptor
Psion Teklogix Mobile Devices SDK Developers Guide
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Chapter 7: Controlling The Power To Card Slots
Controlling Power Through The Windows Control Panel
Psion Teklogix
Computer
NETBOOK PRO
(deprecated)
Card Slot Type
SDK Hardware
Name
Software
Control Of
Power State
Cards Accepted
SD-MMC
SD-MMC
Yes
SD card
CF
PCMCIA Slot 0
Yes
CF card
PCMCIA
PCMCIA Slot 1
Yes
PCMCIA card
CF card in adaptor
Workabout Pro
SD-MMC
SD-MMC
Yes
SD card (memory only)
MMC card (memory only)
Note 1:
Note 2:
CF
PCMCIA Slot 0
Yes
CF card
PCMCIA
(upgradable on
100-pin connector)
PCMCIA Slot 1
(see note 3)
Yes
PCMCIA card
On the 7535, calls to the power state setting method for PCMCIA Slot 1 are ignored.
On the WORKABOUT PRO, when the PCMCIA slot is not installed, calls to the power state setting method for PCMCIA Slot 1 throw an exception.
Power to software-controllable card slots is controlled using the following processes:
•
•
Through the Windows CE Control Panel Power Properties window.
Through application software using the SDK.
The power state can be set by either method. The most recently set state, from whichever source, applies.
7.2 Controlling Power Through The Windows Control Panel
Power to the software-controllable card slots can be controlled through the Windows Control Panel. Psion
Teklogix hand-held computers have a Power icon on the Control Panel. Selecting this icon opens the Power
Properties window; then select the Card Slots tab. For each card slot on the hand-held computer the following
are listed:
•
•
•
The name of the card slot.
One of:
• The name of the peripheral occupying the card slot.
• Disabled.
• Empty Slot.
A checkbox indicating whether the card slot is enabled or disabled.
Clicking on the checkbox, and then clicking on the Apply button, toggles the power state of the card slot.
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Psion Teklogix Mobile Devices SDK Developers Guide
Chapter 7: Controlling The Power To Card Slots
Controlling Power Through The SDK
Refer to the user manual for the Psion Teklogix hand-held, or vehicle-mount, computer for instructions. The
following user guides are available for the Windows CE-based hand-held and vehicle-mount computers:
•
•
•
•
•
•
•
Psion Teklogix 7535 Hand-Held Computer User Manual (Part number 8100007).
7530G2 Hand-Held Computer User Manual (Part number 8100081).
7535G2 Hand-Held Computer User Manual (Part number 8100075).
WORKABOUT PRO M/C Hand-Held Computer User Manual (Part number 8000024).
NETBOOK PRO Hand-Held Computer User Manual (Part number 8100012).
Psion Teklogix 8525/8530 Vehicle-Mount Computer User Manual (Part number 8100038).
8525G2/8530G2 Vehicle-Mount Computer User Manual (Part number 8100083).
7.3 Controlling Power Through The SDK
Each of the API libraries has methods for the following (refer to the documentation for the relevant API
library for details):
Method Purpose
Input & Output
Set the power state
Input: <Hardware name> and <Power state>
Get the power state
Input: <Hardware name>
Output: <Power state>
Where: <Hardware name> identifies the card slot. See “Controlling The Power To Card Slots” on
page 39 for valid values.
<Power state> has one of the following values:
PowerState_Off
PowerState_On
PowerState_Unknown (only valid when querying the power state)
Querying The Power State
When the power state of a card slot is queried, the result is interpreted as follows:
PowerState_Off: This state is returned when one of the following conditions is met:
• There is a card in the slot and the card slot is powered down.
• There is no card in the card slot.
PowerState_On: This state is returned when there is a card in the slot and the slot is powered up.
PowerState_Unknown: This state is returned when the power state of the slot cannot be determined.
Changing The Power State
When a slot is in PowerState_On: It is powered down by one of the following:
•
•
Using the SDK method for setting the power state.
Through the Windows CE Control Panel.
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Chapter 7: Controlling The Power To Card Slots
Card Slot Control API Elements
When a slot is in PowerState_Off: It is powered up by one of the following:
•
•
•
Using the SDK method for setting the power state.
Through the Windows Control Panel.
Performing a clean start of the Windows operating system (requires Psion Teklogix
security level).
Events
If there is a card in the card slot when the power state is changed, the following events are generated:
•
•
Changing the state from PowerState_On to PowerState_Off generates a card removal event.
Changing the state from PowerState_Off to PowerState_On generates a card insertion event.
While the card slot is in PowerState_On, the following events occur:
•
•
Inserting a card generates a card insertion event.
Removing a card generated a card removal event.
While the slot is in PowerState_Off, no card insertion or card removal events are generated.
7.4 Card Slot Control API Elements
C++: The card slots on all Psion Teklogix computers are controlled using the
PsionTeklogix::Peripherals namespace.
Java: The card slots on all Psion Teklogix computers are controlled using the Peripherals class in the
com.teklogix.system package.
.NET: The card slots on all Psion Teklogix computers are controlled using the
PsionTeklogix.Peripherals namespace.
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