I solved my own problem. Thanks Micah for helping.
Nate
--- In msp430@msp4..., "neptunetg" <neptunetg@y...> wrote:
> The demo code is below. I'm using a
MSP430F413. This demo is
> available on TI's website. The header describes exactly what it
> does. All I need is the transmit portion of this code, but I'm
> having a pickle of a time getting it extracted and modified. My
> transmit port is P1.2 . Basically, I want to put an 8 bit value
in
> what they are calling RXTXData, call the routine
and send it out
the
> port 1.2 at 9600 baud. Thanks for replying.
>
> Nate
>
> ;******************************************************************
**
> **********
> ; MSP-FET430P410 Demo - Timer_A, UART 9600 Echo, DCO SMCLK
> ;
> ; Description: Use Timer_A CCR0 hardware output modes and SCCI
> data latch to
> ; implement UART function @ 9600 baud. Software does not
directly
> read and
> ; write to RX and TX pins, instead proper use of output modes
and
> SCCI data
> ; latch are demonstrated. Using these hardware features
eliminates
> ISR
> ; latency effects as hardware ensures that input and output bit
> latching and
> ; timing are perfectly synchronised with Timer_A regardless of
> other
> ; software activity. In the Mainloop the UART function readies
the
> UART to
> ; receive one character and waits in LPM0 with all activity
> interrupt driven.
> ; After a character has been received, the UART receive function
> forces exit
> ; from LPM0 in the Mainloop which echo's back the received
> character.
> ; ACLK = LFXT1 = 32768Hz, MCLK = SMCLK = default DCO = 32 x ACLK
> 1048576Hz
> ; //* An external watch crystal between XIN & XOUT is required
for
> ACLK *//
> ;
> ; MSP430F413
> ; -----------------
> ; /|\| XIN|-
> ; | | | 32kHz
> ; --|RST XOUT|-
> ; | |
> ; | P1.0/CCI0A/TX|-------->
> ; | | 9600 8N1
> ; | P1.1/CCI0B/RX|<--------
> ;
> ; M. Buccini
> ; Texas Instruments Inc.
> ; Feb 2005
> ; Built with IAR Embedded Workbench Version: 3.21A
> ;******************************************************************
**
> **********
> #include <msp430x41x.h>
>
> ; CPU Registers Used
> #define RXTXData R4
> #define BitCnt R5
> ;
> RXD EQU 002h ; RXD on P1.1
> TXD EQU 001h ; TXD on P1.0
> ;
> ; Conditions for 9600 Baud SW UART, SMCLK = 1048576
> Bitime_5 EQU 0055 ; ~ 0.5 bit length
> Bitime EQU 0109 ; ~ 9620 baud
> ;
> ;------------------------------
--
> ----------
> ORG 0E000h ;
> ;------------------------------
--
> ----------
> RESET mov.w #300h,SP ; Initialize
stackpointer
> SetupWDT mov.w #WDTPW+WDTHOLD,&WDTCTL
; Stop Watchdog Timer
> SetupFLL bis.b #XCAP14PF,&FLL_CTL0 ; Configure load caps
> SetupTA mov.w #TASSEL1+MC1,&TACTL ; SMCLK, continous mode
> SetupC0 mov.w #OUT,&CCTL0 ; TXD Idle as Mark
> SetupP1_2 bis.b #TXD+RXD,&P1SEL ; P1.0/1 TA0 for
TXD/RXD
> function
> bis.b #TXD,&P1DIR ; TXD output on P1
> eint ; Enable general
> interrupts
> ;
> Mainloop call #RX_Ready ; UART ready to RX one
> Byte
> bis.w #LPM0,SR ; Enter LPM0 Until
Byte
> RXed
> call #TX_Byte ; TX Back RXed Byte
> Received
> jmp Mainloop ;
> ;
> ;------------------------------
--
> ----------
> TX_Byte ; Subroutine Transmits Character from RXTXData Buffer
> ;------------------------------
--
> ----------
> mov.w &TAR,&CCR0 ; Current state of TA
> counter
> add.w #Bitime,&CCR0 ; Some time till first
> bit
> bis.w #0100h, RXTXData ; Add mark stop bit to
> RXTXData
> rla.w RXTXData ; Add space start bit
> mov.w #10,BitCnt ; Load Bit counter,
> 8data + ST/SP
> mov.w #OUTMOD0+CCIE,&CCTL0 ; TXD = mark = idle
> TX_Wait bit.w #CCIE,&CCTL0 ; Wait for TX
completion
> jnz TX_Wait ;
> ret ;
> ;
> ;------------------------------
--
> ----------
> RX_Ready ; Subroutine Readies UART to Receive Character into
> RXTXData Buffer
> ;------------------------------
--
> ----------
> mov.w #08,BitCnt ; Load Bit Counter, 8
> data bits
> SetupRX mov.w
#SCS+CCIS0+OUTMOD0+CM1+CAP+CCIE,&CCTL0 ;
> Sync,Neg Edge,cap
> ret ;
> ;
> ;------------------------------
--
> ----------
> TA0_ISR ; RXTXData Buffer holds UART Data
> ;------------------------------
--
> ----------
> add.w #Bitime,&CCR0 ; Time to next bit
> bit.w #CCIS0,&CCTL0 ; RX on CCI0B?
> jnz UART_RX ; Jump --> RX
> UART_TX cmp.w #00h,BitCnt ;
> jne TX_Next ; Next bit?
> bic.w #CCIE,&CCTL0 ; All Bits TX or RX,
> Disable Int.
> reti ;
> TX_Next bic.w #OUTMOD2,&CCTL0 ; TX Mark
> rra.w RXTXData ; LSB is shifted to
carry
> jc TX_Test ; Jump
--> bit = 1
> TX_Space bis.w #OUTMOD2,&CCTL0 ; TX Space
> TX_Test dec.w BitCnt ; All bits sent (or
> received)?
> reti ;
> ;
> UART_RX bit.w #CAP,&CCTL0 ; Capture mode = start
> bit edge
> jz RX_Bit ; Start bit edge?
> RX_Edge bic.w #CAP,&CCTL0 ; Switch to compare
mode
> add.w #Bitime_5,&CCR0 ;
First databit 1.5
bits
> from edge
> reti ;
> RX_Bit bit.w #SCCI,&CCTL0 ; Get bit waiting in
> receive latch
> rrc.b RXTXData ; Store received bit
> RX_Test dec.w BitCnt ; All bits RXed?
> jnz RX_Next ; Next bit?
> ;>>>>>>>>>> Decode of Received Byte Here
>
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
> RX_Comp bic.w #CCIE,&CCTL0 ; All bits RXed,
disable
> interrupt
> mov.w #GIE,0(SP) ; Decode byte = active
> in Mainloop
>
;>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<
<<
> <<<<<<<<<
> RX_Next reti ;
> ;
> ;------------------------------
--
> ----------
> ; Interrupt Vectors
> ;------------------------------
--
> ----------
> ORG 0FFFEh ; RESET Vector
> DW RESET ;
> ORG 0FFECh ; Timer_A0 Vector
> DW TA0_ISR ;
The demo code is below. I'm using a MSP430F413. This demo is
available on TI's website. The header describes exactly what it
does. All I need is the transmit portion of this code, but I'm
having a pickle of a time getting it extracted and modified. My
transmit port is P1.2 . Basically, I want to put an 8 bit value in
what they are calling RXTXData, call the routine and send it out the
port 1.2 at 9600 baud. Thanks for replying.
Nate
;********************************************************************
**********
; MSP-FET430P410 Demo - Timer_A, UART 9600 Echo, DCO SMCLK
;
; Description: Use Timer_A CCR0 hardware output modes and SCCI
data latch to
; implement UART function @ 9600 baud. Software does not directly
read and
; write to RX and TX pins, instead proper use of output modes and
SCCI data
; latch are demonstrated. Using these hardware features eliminates
ISR
; latency effects as hardware ensures that input and output bit
latching and
; timing are perfectly synchronised with Timer_A regardless of
other
; software activity. In the Mainloop the UART function readies the
UART to
; receive one character and waits in LPM0 with all activity
interrupt driven.
; After a character has been received, the UART receive function
forces exit
; from LPM0 in the Mainloop which echo's back the received
character.
; ACLK = LFXT1 = 32768Hz, MCLK = SMCLK = default DCO = 32 x ACLK 1048576Hz
; //* An external watch crystal between XIN & XOUT is required for
ACLK *//
;
; MSP430F413
; -----------------
; /|\| XIN|-
; | | | 32kHz
; --|RST XOUT|-
; | |
; | P1.0/CCI0A/TX|-------->
; | | 9600 8N1
; | P1.1/CCI0B/RX|<--------
;
; M. Buccini
; Texas Instruments Inc.
; Feb 2005
; Built with IAR Embedded Workbench Version: 3.21A
;********************************************************************
**********
#include <msp430x41x.h>
; CPU Registers Used
#define RXTXData R4
#define BitCnt R5
;
RXD EQU 002h ; RXD on P1.1
TXD EQU 001h ; TXD on P1.0
;
; Conditions for 9600 Baud SW UART, SMCLK = 1048576
Bitime_5 EQU 0055 ; ~ 0.5 bit length
Bitime EQU 0109 ; ~ 9620 baud
;
;--------------------------------
----------
ORG 0E000h ;
;--------------------------------
----------
RESET mov.w #300h,SP ; Initialize stackpointer
SetupWDT mov.w #WDTPW+WDTHOLD,&WDTCTL ; Stop Watchdog Timer
SetupFLL bis.b #XCAP14PF,&FLL_CTL0 ; Configure load caps
SetupTA mov.w #TASSEL1+MC1,&TACTL ; SMCLK, continous mode
SetupC0 mov.w #OUT,&CCTL0 ; TXD Idle as Mark
SetupP1_2 bis.b #TXD+RXD,&P1SEL ; P1.0/1 TA0 for TXD/RXD
function
bis.b #TXD,&P1DIR ; TXD output on P1
eint ; Enable general
interrupts
;
Mainloop call #RX_Ready ; UART ready to RX one
Byte
bis.w #LPM0,SR ; Enter LPM0 Until Byte
RXed
call #TX_Byte ; TX Back RXed Byte
Received
jmp Mainloop ;
;
;--------------------------------
----------
TX_Byte ; Subroutine Transmits Character from RXTXData Buffer
;--------------------------------
----------
mov.w &TAR,&CCR0 ; Current state of TA
counter
add.w #Bitime,&CCR0 ; Some time till first
bit
bis.w #0100h, RXTXData ; Add mark stop bit to
RXTXData
rla.w RXTXData ; Add space start bit
mov.w #10,BitCnt ; Load Bit counter,
8data + ST/SP
mov.w #OUTMOD0+CCIE,&CCTL0 ; TXD = mark = idle
TX_Wait bit.w #CCIE,&CCTL0 ; Wait for TX completion
jnz TX_Wait ;
ret ;
;
;--------------------------------
----------
RX_Ready ; Subroutine Readies UART to Receive Character into
RXTXData Buffer
;--------------------------------
----------
mov.w #08,BitCnt ; Load Bit Counter, 8
data bits
SetupRX mov.w
#SCS+CCIS0+OUTMOD0+CM1+CAP+CCIE,&CCTL0 ;
Sync,Neg Edge,cap
ret ;
;
;--------------------------------
----------
TA0_ISR ; RXTXData Buffer holds UART Data
;--------------------------------
----------
add.w #Bitime,&CCR0 ; Time to next bit
bit.w #CCIS0,&CCTL0 ; RX on CCI0B?
jnz UART_RX ; Jump --> RX
UART_TX cmp.w #00h,BitCnt ;
jne TX_Next ; Next bit?
bic.w #CCIE,&CCTL0 ; All Bits TX or RX,
Disable Int.
reti ;
TX_Next bic.w #OUTMOD2,&CCTL0 ; TX Mark
rra.w RXTXData ; LSB is shifted to carry
jc TX_Test ; Jump --> bit = 1
TX_Space bis.w #OUTMOD2,&CCTL0 ; TX Space
TX_Test dec.w BitCnt ; All bits sent (or
received)?
reti ;
;
UART_RX bit.w #CAP,&CCTL0 ; Capture mode = start
bit edge
jz RX_Bit ; Start bit edge?
RX_Edge bic.w #CAP,&CCTL0 ; Switch to compare mode
add.w #Bitime_5,&CCR0 ; First databit 1.5 bits
from edge
reti ;
RX_Bit bit.w #SCCI,&CCTL0 ; Get bit waiting in
receive latch
rrc.b RXTXData ; Store received bit
RX_Test dec.w BitCnt ; All bits RXed?
jnz RX_Next ; Next bit?
;>>>>>>>>>> Decode of Received Byte Here
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
RX_Comp bic.w #CCIE,&CCTL0 ; All bits RXed, disable
interrupt
mov.w #GIE,0(SP) ; Decode byte = active
in Mainloop
;>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<
<<<<<<<<<
RX_Next reti ;
;
;--------------------------------
----------
; Interrupt Vectors
;--------------------------------
----------
ORG 0FFFEh ; RESET Vector
DW RESET ;
ORG 0FFECh ; Timer_A0 Vector
DW TA0_ISR ;
Reply by Micah Stevens●July 29, 20052005-07-29
Send your routine, and also the type of MSP you're using..
On Friday 29 July 2005 9:39 am, neptunetg wrote:
> Can anyone please help me? I'm having a rather difficult time
> implementing a UART Transmit at 9600 Baud. I have been trying to
> modify the APP NOTE that waits for a character to be received and then
> echos that character. I just want to write an ASCII character to the
> UART. I am using port 1.2 for my output and I don't know if thats
> complicating matters or not. Any code snippet would be greatly
> appreciated.
>
> Thanks!
>
>
>
>
>
>
> .
>
>
>
>
>
>
> SPONSORED LINKS
> Msp430 Texas instruments Hardware
>
>
> .
Reply by neptunetg●July 29, 20052005-07-29
Can anyone please help me? I'm having a rather difficult time
implementing a UART Transmit at 9600 Baud. I have been trying to
modify the APP NOTE that waits for a character to be received and then
echos that character. I just want to write an ASCII character to the
UART. I am using port 1.2 for my output and I don't know if thats
complicating matters or not. Any code snippet would be greatly
appreciated.
Thanks!
