Generating a PWM Signal Modulated by an Analog Input
EVM Application #4
Generating a PWM
Signal Modulated by an
Analog Input Using the
TMS320F240 EVM
APPLICATION REPORT: SPRA413
David Figoli
Digital Signal Processing Solutions
January 1999
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Contents
Abstract ......................................................................................................................... 7
Product Support............................................................................................................ 8
World Wide Web ....................................................................................................... 8
Email......................................................................................................................... 8
Overview........................................................................................................................ 9
Module(s) Used......................................................................................................... 9
Input ......................................................................................................................... 9
Output ....................................................................................................................... 9
Background and Methodology................................................................................... 10
Analog-to-Digital Converter ....................................................................................... 11
test
EVM Application #4
Generating a PWM Signal Modulated
by an Analog Input Using the
TMS320F240 EVM
Abstract
This EVM application converts an input value with the analog-todigital converter (ADC) module of the Texas Instruments (TIä)
TMS320F240 Evaluation Module (EVM) and outputs a pulse width
modulated (PWM) signal corresponding to the digital conversion
of the analog input.
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
7
SPRA413
Product Support
World Wide Web
Our World Wide Web site at www.ti.com contains the most up to
date product information, revisions, and additions. Users
registering with TI&ME can build custom information pages and
receive new product updates automatically via email.
Email
For technical issues or clarification on TI products, please send a
detailed email to dsph@ti.com. Questions receive prompt
attention and are usually answered within one business day.
8
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
SPRA413
Overview
This application converts an input value with the analog-to-digital
converter (ADC) module of the TI TMS320F240 EVM and outputs
a pulse width modulated (PWM) signal corresponding to the digital
conversion of the analog input. In other words, the pulse width of
the PWM signal will be proportional to the input value and
represents an equivalent analog output signal. The PWM signal
will be created asymmetrically. This application is implemented
using C2xx Assembly code. The algorithm described in this
application report was implemented using the TMS320F240 EVM.
Module(s) Used
q
q
q
10 bit Analog-to-Digital Converter
Event Manager Module
General Purpose Timer 1
Input
ADCIN0
Output
T1PWM / T1CMP
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
9
SPRA413
Background and Methodology
This application uses the ADC and the Event Manager Module to
convert an input signal (with the ADC) and output a proportional
pulse width signal (with a General Purpose Timer of the Event
Manager). The setup of this program is similar to the setup for
Application #2 (PWM1.ASM) except instead of going to a look-up
table to find the next value for the compare register, the program
uses the value that is located in the ADCFIFO register.
The initial setup of the PWM signal is similar to the setup that was
done for Application #1 and #2. The PLL Module, Digital I/O Port,
and the Event Manager Module need to be set up properly to set
up the PWM signal. Similar to the Timer Module of the Event
Manager Module, the ADC also shares some of its pins with the
pins of the I/O Port. As a result, in the setup of the Digital I/O Port,
the Event Manager Module and the ADC need to be configured so
that their respective pins are TxPWM/TxCMP outputs and ADCINx
inputs, rather than generic I/O pins.
Similar to Application #2 (PWM1.ASM), this application uses the
General Purpose Timer's period register to generate an interrupt
that updates the compare register.
10
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
SPRA413
Analog-to-Digital Converter
Once the Event Manager registers are set up to generate a PWM
signal, then the ADC needs to be set up. Since the ADC has a
FIFO register that can store two converted values at a time, the
ADC can be set up to convert continuously. By converting
continuously, the ADC's values will not be dependent on the
interrupt service routine to be restarted. Because the ADC will be
converting continuously, the value that is in the ADCFIFO register
will be a recent conversion.
Because the ADC has a resolution of 10 bits and the registers of
the timers are 16 bits, scaling has to be done so that the resulting
pulse width can have a duty cycle of 0 to 100 percent of the PWM
period. The ADC converts the input values and places them into
the ADCFIFO register. The ADCFIFO register is 16 bits wide, yet
the ADC only has a 10 bit resolution. As a result the converted
value’s most significant bit occupies the most significant bit of the
register, thereby always leaving the 6 least significant bits of the
register filled with zeros.
If the values in the ADCFIFO register were used without
modification, the pulse width would have a discontinuity as the
input value went from 1/1024 of Vref to 0V. This discontinuity would
result because the compare register would switch from 40h to 00h
during the transition from 1/1024 of Vref to 0V. To avoid this
discontinuity, the ADCFIFO register result is shifted to the right so
that the least significant bit, which resided at bit 6, now resides at
bit 0. By shifting ADCFIFO, the maximum values go from FFC0h
to 3FFh, and the minimum value (above 0) goes from 40h to 1h.
By shifting the ADCFIFO results, the period register can be set to
a 10 bit maximum of 3FFh. Because the period register is set to
the maximum value 3FFh, with the CPUCLK at 20MHz, the
resulting PWM frequency will be 19.5kHz.
Like the previous applications, this application is interrupt driven,
and once the registers are set up, the program can be ended. The
PWM output continues to run because of the interrupt structure,
but when the program is halted, the PWM signal stops.
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
11
SPRA413
;******************************************************************
; File Name:
adc0.asm
; Originator:
Digital Control systems Apps group - Houston
; Target System:
'C24x Evaluation Board
;
; Description:
Uses the ADC and outputs the conversion to the
;
compare register of the Event Manager to modify
;
duty cycle of a PWM signal in proportion to the
;
input analog value.
; Last Updated:
;
20 June 1997
; *********************************************************************
.include f240regs.h
; --------------------------------------------------------------------
; I/O Mapped EVM Registers
; --------------------------------------------------------------------
DAC0
DAC1
DAC2
DAC3
DACUPDATE
.set
.set
.set
.set
.set
0000h
0001h
0002h
0003h
0004h
;Input data
;Input data
;Input data
;Input data
;DAC Update
register
register
register
register
Register
for
for
for
for
DAC0
DAC1
DAC2
DAC3
;---------------------------------------------------------------------
; Variable Declarations for B2
;---------------------------------------------------------------------
.bss
.bss
.bss
.bss
.bss
GPR0,1
DAC0VAL,1
DAC1VAL,1
DAC2VAL,1
DAC3VAL,1
;General Purpose Register
;DAC0 Channel Value
;DAC0 Channel Value
;DAC0 Channel Value
;DAC0 Channel Value
;---------------------------------------------------------------------
; Vector address declarations
;---------------------------------------------------------------------
RSVECT
INT1
INT2
INT3
INT4
INT5
INT6
RESERVED
SW_INT8
SW_INT9
SW_INT10
SW_INT11
SW_INT12
SW_INT13
SW_INT14
SW_INT15
SW_INT16
TRAP
12
.sect
B
B
B
B
B
B
B
B
B
B
B
B
B
B
B
B
B
B
".vectors"
START
PHANTOM
CHG_CMPR
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Reset Vector
Interrupt Level 1
Interrupt Level 2
Interrupt Level 3
Interrupt Level 4
Interrupt Level 5
Interrupt Level 6
Reserved
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
Trap vector
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
SPRA413
NMINT
EMU_TRAP
SW_INT20
SW_INT21
SW_INT22
SW_INT23
B
B
B
B
B
B
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
PHANTOM
;
;
;
;
;
;
Non-maskable Interrupt
Emulator Trap
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
User S/W Interrupt
;=====================================================================
; M A I N
C O D E
- starts here
;=====================================================================
START:
SETC
.text
NOP
INTM
;Disable interrupts
SPLK #0002h,IMR ;Mask all interrupts except INT2
LACC IFR
;Read Interrupt flags
SACL IFR
;Clear all interrupt flags
CLRC SXM
CLRC OVM
CLRC CNF
;Clear Sign Extension Mode
;Reset Overflow Mode
;Config Block B0 to Data mem
;-----------------------------------
; Set up PLL Module
;-----------------------------------
LDP
#00E0h
;The following line is necessary if a previous program set the PLL
;to a different setting than the settings which the application
;uses. By disabling the PLL, the CKCR1 register can be modified so
;that the PLL can run at the new settings when it is re-enabled.
SPLK #0000000001000001b,CKCR0 ;CLKMD=PLL Disable
;SYSCLK=CPUCLK/2
;
5432109876543210
SPLK #0000000010111011b,CKCR1 ;CLKIN(OSC)=10MHz
;CPUCLK=20MHz
;CKCR1 - Clock Control Register 1
;
Bits 7-4
(1011)CKINF(3)-CKINF(0) - Crystal or Clock-In
Frequency
;
Frequency = 10MHz
;
Bit 3
(1)
PLLDIV(2) - PLL divide by 2 bit
;
Divide PLL input by 2
;
Bits 2-0
(011) PLLFB(2)-PLLFB(0) - PLL multiplication ratio
;
PLL Multiplication Ratio = 4
;
SPLK
5432109876543210
#0000000011000011b,CKCR0 ;CLKMD=PLL Enable
;SYSCLK=CPUCLK/2
;CKCR0 - Clock Control Register 0
;
Bits 7-6
(11) CLKMD(1),CLKMD(0) - Operational mode of Clock
; Module PLL Enabled
; Run on CLKIN on exiting low power mode
;
Bits 5-4
(00) PLLOCK(1),PLLOCK(0) - PLL Status. READ ONLY
;
Bits 3-2
(00) PLLPM(1),PLLPM(0) - Low Power Mode - LPM0
;
Bit 1
(0)
ACLKENA - 1MHz ACLK Enable
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
13
SPRA413
;
;
;
Bit 0
;
(1)
ACLK Enabled
PLLPS - System Clock Prescale Value
f(sysclk)=f(cpuclk)/2
5432109876543210
SPLK #0100000011000000b,SYSCR ;CLKOUT=CPUCLK
;SYSCR - System Control Register
;
Bit 15-14
(01) RESET1,RESET0 - Software Reset Bits
;
No Action
;
Bits 13-8
(000000)
Reserved
;
Bit 7-6
(11) CLKSRC1,CLKSRC0 - CLKOUT-Pin Source Select
;
CPUCLK: CPU clock output mode
;
Bit 5-0
(000000)
Reserved
SPLK #006Fh, WDCR
KICK_DOG
;Disable WD if VCCP=5V
;
(JP6 in pos. 2-3)
;Reset Watchdog
;-----------------------------------
; Set up Digital I/O Port
;-----------------------------------
LDP
;
#225
;DP=225, Data Page to Configure OCRA
5432109876543210
SPLK #0011100000001111b,OCRA
;OCRA - Output Control Register A
;
Bit 15
(0)
CRA.15 - IOPB7
;
Bit 14
(0)
CRA.14 - IOPB6
;
Bit 13
(1)
CRA.13 - T3PWM/T3CMP
;
Bit 12
(1)
CRA.12 - T2PWM/T2CMP
;
Bit 11
(1)
CRA.11 - T1PWM/T1CMP
;
Bit 10
(0)
CRA.10 - IOPB2
;
Bit 9
(0)
CRA.9 - IOPB1
;
Bit 8
(0)
CRA.8 - IOPB0
;
Bits 7-4
(0000)Reserved
;
Bit 3
(1)
CRA.3 - ADCIN8
;
Bit 2
(1)
CRA.2 - ADCIN9
;
Bit 1
(1)
CRA.1 - ADCIN1
;
Bit 0
(1)
CRA.0 - ADCIN0
;*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-
;- Event Manager Module Reset
;*
;This section resets all of the Event Manager Module
;
Registers. This is necessary for silicon revision 1.1;
;
but not necessary for silicon revisions 2.0 and later.
;*
;;*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-
LDP
SPLK
14
#232
;DP=232 Data Page for the Event Manager
#0000h,GPTCON ;Clear General Purpose Time Control
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
SPRA413
SPLK
SPLK
SPLK
#0000h,T1CON
#0000h,T2CON
#0000h,T3CON
SPLK
SPLK
#0000h,COMCON ;Clear Compare Control
#0000h,ACTR
;Clear Full Compare Action Control
Register
#0000h,SACTR ;Clear Simple Compare Action
Control Register
#0000h,DBTCON ;Clear Dead-Band Timer Control
Register
;
SPLK
;
SPLK
;
;Clear GP Timer 1 Control
;Clear GP Timer 2 Control
;Clear GP Timer 3 Control
SPLK
#0000h,CAPCON ;Clear Capture Control
SPLK
SPLK
SPLK
#0FFFFh,EVIFRA ;Clear Interrupt Flag Register A
#0FFFFh,EVIFRB ;Clear Interrupt Flag Register B
#0FFFFh,EVIFRC ;Clear Interrupt Flag Register C
SPLK
SPLK
SPLK
#0000h,EVIMRA ;Clear Event Manager Mask Register A
#0000h,EVIMRB ;Clear Event Manager Mask Register B
#0000h,EVIMRC ;Clear Event Manager Mask Register C
;*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-
;-
End of RESET section for silicon revision 1.1
*
;*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*;-----------------------------------
; Set up Event Manager Module
;-----------------------------------
T1COMPARE
T1PERIOD
.set 11111111b
.set 1111111111b
LDP
;
;
;
;Value does not matter
;Maximum ADC Value
#232
;DP=232, Data Page for Event
Manager Addresses
SPLK #T1COMPARE,T1CMPR
;Compare value for 50%
duty cycle
2109876543210
SPLK #0000001010101b,GPTCON
;GPTCON - GP Timer Control Register
;
Bit 15
(0)
T3STAT - GP Timer 3 Status. READ ONLY
;
Bit 14
(0)
T2STAT - GP Timer 2 Status. READ ONLY
;
Bit 13
(0)
T1STAT - GP Timer 1 Status. READ ONLY
;
Bits 12-11
(00) T3TOADC - ADC start by event of GP Timer 3
;
No event starts ADC
;
Bits 10-9
(00) T2TOADC - ADC start by event of GP Timer 2
;
No event starts ADC
;
Bits 8-7
(00) T1TOADC - ADC start by event of GP Timer 1
;
No event starts ADC
;
Bit 6
(1)
TCOMPOE - Compare output enable
;
Enable all three GP timer compare outputs
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
15
SPRA413
;
;
;
;
;
;
Bits 5-4
Bits 3-2
Bits 1-0
SPLK
SPLK
SPLK
SPLK
(01) T3PIN - Polarity of GP Timer 3 compare
output, Active Low
(01) T2PIN - Polarity of GP Timer 2 compare
output, Active Low
(01) T1PIN - Polarity of GP Timer 1 compare
output, Active Low
#T1PERIOD,T1PR
#0000h,T1CNT
#0000h,T2CNT
#0000h,T3CNT
;
SPLK
;Period value for
;Clear GP Timer 1
;Clear GP Timer 2
;Clera GP Timer 3
20kHz signal
Counter
Counter
Counter
5432109876543210
#0001000000001010b,T1CON
;T1CON - GP Timer 1 Control Register
; Bits 15-14
(00) FREE,SOFT - Emulation Control Bits
;
Stop immediately on emulation suspend
;
Bits 13-11
(010) TMODE2-TMODE0 - Count Mode Selection
;
Continuous-Up Count Mode
;
Bits 10-8
(000) TPS2-TPS0 - Input Clock Prescaler
;
Divide by 1
;
Bit 7
(0)
Reserved
;
Bit 6
(0)
TENABLE - Timer Enable
;
Disable timer operations
;
Bits 5-4
(00) TCLKS1,TCLKS0 - Clock Source Select
;
Internal Clock Source
;
Bits 3-2
(10) TCLD1,TCLD0 - Timer Compare Register
;
Reload Condition Immediately
;
Bit 1
(1)
TECMPR - Timer compare enable
;
Enable timer compare operation
;
Bit 0
(0)
Reserved
;
5432109876543210
SPLK #0000000000000000b,T2CON
;GP Timer 2 - Not Used
;T2CON - GP Timer 2 Control Register
;
Bits 15-14
(00) FREE,SOFT - Emulation Control Bits
;
Stop immediately on emulation suspend
;
Bits 13-11
(000) TMODE2-TMODE0 - Count Mode Selection
;
Stop/Hold
;
Bits 10-8
(000) TPS2-TPS0 - Input Clock Prescaler
;
Divide by 1
;
Bit 7
(0)
TSWT1 - GP Timer 1 timer enable bit
;
Use own TENABLE bit
;
Bit 6
(0)
TENABLE - Timer Enable
;
Disable timer operations
;
Bits 5-4
(00) TCLKS1,TCLKS0 - Clock Source Select
;
Internal Clock Source
;
Bits 3-2
(00) TCLD1,TCLD0 - Timer Compare Register
16
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
SPRA413
;
;
;
;
;
;
;
Bit 1
(0)
Bit 0
(0)
Reload Condition
When counter is 0
TECMPR - Timer compare enable
Disable timer compare operation
SELT1PR - Period Register select
Use own period register
5432109876543210
SPLK #0000000000000000b,T3CON
;GP Timer 3 - Not Used
;T3CON - GP Timer 3 Control Register
;
Bits 15-14
(00) FREE,SOFT - Emulation Control Bits
;
Stop immediately on emulation suspend
;
Bits 13-11
(000) TMODE2-TMODE0 - Count Mode Selection
;
Stop/Hold
;
Bits 10-8
(000) TPS2-TPS0 - Input Clock Prescaler
;
Divide by 1
;
Bit 7
(0)
TSWT1 - GP Timer 1 timer enable bit
;
Use own TENABLE bit
;
Bit 6
(0)
TENABLE - Timer Enable
;
Disable timer operations
;
Bits 5-4
(00) TCLKS1,TCLKS0 - Clock Source Select
;
Internal Clock Source
;
Bits 3-2
(00) TCLD1,TCLD0 - Timer Compare Register
;
Reload Condition
;
When counter is 0
;
Bit 1
(0)
TECMPR - Timer compare enable
;
Disable timer compare operation
;
Bit 0
(0)
SELT1PR - Period Register select
;
Use own period register
;
5432109876543210
SPLK #0000000010000000b,EVIMRA ;Enables the T1PINT
;-----------------------------------
; Set up ADC Module
;-----------------------------------
LDP
;
#224
;DP = 224 Data Page for ADC Registers
5432109876543210
SPLK #1000110100000000b,ADCTRL1
;ADCTRL1 - ADC Control Register 1
;
Bit 15
(1)
Suspend-SOFT ;
Complete Conversion before halting emulator
;
Bit 14
(0)
Suspend-FREE ;
Operations is determined by Suspend-SOFT
;
Bit 13
(0)
ADCIMSTART - ADC start converting immediately
;
Immediate Start of Conversion
;
Bit 12
(0)
ADC2EN - Enable/Disable ADC2
;
Disable ADC2
;Bit 11
(1)
ADC1EN - Enable/Disable ADC1
;
Enable ADC1
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
17
SPRA413
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Bit 10
Bit 9
Bit 8
Bit 7
Bits 6-4
Bits 3-1
Bit 0
(1)
ADCCONRUN - ADC Continuous Conversion Mode
Continuous Conversion
(1)
ADCINTEN - Enable ADC Interrupt
Request Interrupt when ADCINTFLAG is set
(1)
ADCINTFLAG - ADC Interrupt Flag
Clear Interrupt Flab Bit
(0)
ADCEOC - End of Conversion Bit READ ONLY
(000) ADC2CHSEL - ADC2 Channel Select
Channel 8
(000) ADC1CHSEL - ADC1 Channel Select
Channel 0
(0)
ADCSOC - ADC Start of conversion bit
No Action
5432109876543210
SPLK #0000000000000101b,ADCTRL2
;ADCTRL2 - ADC Control Register 2
;
Bits 15-11
(00000)Reserved
;
Bit 10
(0)
ADCEVSOC - Event Manager SOC mask bit
;
Mask ADCEVSOC
;
Bit 9
(0)
ADCEXTSOC - External SOC mask bit
;
Mask ADCEXTSOC
;
Bit 8
(0)
Reserved
;
Bits 7-6
(00) ADCFIFO1 - Data Register FIFO1 Status
;
READ ONLY
;
Bit 5
(0)
Reserved
;
Bits 4-3
(00) ADCFIFO2 - Data Register FIFO2 Status
;
READ ONLY
;
Bits 2-0
(101) ADCPSCALE - ADC Input Clock Prescaler
;
Prescale Value 16
;
SYSCLK Period = 0.1usec
;
0.1usec x 16 x 6 = 9.6 usec >= 6usec
;----------------------------------; Set up EVM DAC Module
;----------------------------------;This section lets youuse the DAC as an input into the ADC if
; there is not an easily available source(a waveform generator).
LDP
#0
SPLK #4h,GPR0
OUT
GPR0,WSGR
18
SPLK
SPLK
SPLK
SPLK
#03FFh,DAC0VAL
#07FFh,DAC1VAL
#0BFFh,DAC2VAL
#0FFFh,DAC3VAL
OUT
OUT
DAC0VAL,DAC0
DAC1VAL,DAC1
;The DAC requires that
;I/O accesses require 1WS
;DACOUT0 = 1.25V
;DACOUT1 = 2.50V
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
SPRA413
OUT
OUT
OUT
;
DAC2VAL,DAC2
;DACOUT2 = 3.75V
DAC3VAL,DAC3
;DACOUT3 = 5.00V
DAC3VAL,DACUPDATE
;Output the values on the
DAC pins
LDP
#232
SBIT1 T1CON,B6_MSK
;Sets Bit 6 of T1CON
;T1CON - GP Timer 1 Control Register
;
Bit 6
(1)
TENABLE - Timer Enable
;
Enable Timer Operations
LDP
#224
SBIT1 ADCTRL1,B0_MSK
CLRC INTM
END
B
;Sets Bit 0 of ADCTRL1
;Enable Interrupts
END
;-----------------------------------------------------------------------------
;Interrupt Service Routine that Changes the Compare Register
;-----------------------------------------------------------------------------
CHG_CMPR
LDP
#224
;DP = 224 Data Page for ADC Registers
LACC ADCTRL1 ;ACC = ADCTRL1 \ Clears the ADC Int
SACL ADCTRL1 ;ADCTRL1 = ACC / flag if set
LACC ADCFIFO1 ;Load the converted value
RPT
#5
;Shift the value to the right 6 times
SFR
;since 6 LSBs are always 0
LDP
#232
;
SACL T1CMPR
LACC EVIFRA
;
SACL EVIFRA
CLRC INTM
RET
;DP = 232 Data Page for Event
Manager Module
;Store ADC Value into T1CMPR
;ACC = EVIFRA \ Clears the
EVIFR Int
;EVIFRA = ACC / Flags if set
;Enable Interrupts
;===================================================================
; I S R - PHANTOM
;
; Description:
Dummy ISR, used to trap spurious interrupts.
;
; Modifies:
Nothing
;
; Last Update:
16 June 95
;===================================================================
PHANTOM
KICK_DOG
;Resets WD counter
B PHANTOM
Generating a PWM Signal Modulated by an Analog Input Using the TMS320F240 EVM
19
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