MSP430 Timer_A UART

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Hey there,

I'm trying to make a simple project work. There's a demo:
MSP430F20xx Demo - Timer_A, Ultra-Low Pwr UART 2400 Echo, 32kHz ACLK
from TI, it does work but I wanted to use p1.2&p1.6 ports instead of
p1.1&p1.5
(TA1 instead of TA0) so I changed lines


RXD EQU 002h ; RXD on P1.1
TXD EQU 020h ; TXD on P1.5


with


RXD EQU 004h ; RXD on P1.2
TXD EQU 040h ; TXD on P1.6


after that I changed &CCTL0 and &CCR0 with &CCTL1 and &CCR1
respectively.
It won't work Any suggestions?


This is the code:


RXD equ 004h ; RXD on P1.2
TXD equ 040h ; TXD on P1.6


; RAM Registers Used
RXTXData equ 0200h ; Register for RX or TX UART
Data
BitCnt equ 0202h ; Register used to count UART
bits
MYTXA equ 'A'
;
; Conditions for 1200 Baud SW UART, ACLK = 32768
Bitime_5 equ 014 ; .5 bit length + small
adjustment
Bitime equ 027 ; 427us bit length ~ 2341 baud


;--------------------------------------------------------------------------­---



ORG 0F800h ; Program Start
;--------------------------------------------------------------------------­---



RESET mov.w #280h,SP ; Initialize Stackpointer
call #Init_Sys ; Initialize System
Peripherals
again
mov.w &MYTXA,&RXTXData
call #TX_Byte ; TX Back RXed Byte
Received
jmp again


Mainloop call #RX_Ready ; UART ready to RX one Byte

bis.w #LPM3,SR ; Enter LPM3 Until Byte
RXed
call #TX_Byte ; TX Back RXed Byte
Received
jmp Mainloop ;
;
;--------------------------------------------------------------------------­---



Init_Sys ; Subroutine to set-up peripherals
;--------------------------------------------------------------------------­---



StopWDT mov.w #WDTPW+WDTHOLD,&WDTCTL ; Stop WDT
SetupTA mov.w #TASSEL0+MC1,&TACTL ; ACLK, continous mode
SetupC0 mov.w #OUT,&CCTL1 ; TXD Idle as Mark
SetupP1_2 bis.b #TXD,&P1SEL ; P1.1/TA0 for TXD function

bis.b #TXD,&P1DIR ; TXD output on P1
bis.b #RXD,&P1SEL ; P2.2/TA0 as RXD input
eint ; General Enable Interrupts

ret ;
;
;--------------------------------------------------------------------------­---



TX_Byte ; Subroutine that Transmit One Byte from RXTXData Buffer.
;--------------------------------------------------------------------------­---



TX_1 mov.w &TAR,&CCR1 ; Current state of TA
counter
cmp.w &TAR,&CCR1 ; !!Prevent async
capature!!
jne TX_1
add.w #Bitime,&CCR1 ; 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, 8 data
+ SP
mov.w #OUTMOD0+CCIE,&CCTL1 ; TXD = mark = idle
;CCIS0+
TX_Wait bit.w #CCIE,&CCTL1 ; Wait for TX completion
jnz TX_Wait ;
ret ;
;
;--------------------------------------------------------------------------­---



RX_Ready ; Subroutine that will Receive One Byte into RXTXData Buffer.

;--------------------------------------------------------------------------­---



mov.w #08,&BitCnt ; Load Bit Counter, 8 data

bits
SetupRX mov.w #SCS+CCIS0+OUTMOD0+CM1+CAP+CCIE,&CCTL1 ; Sync,Neg
Edge,Cap
ret ;
;
;--------------------------------------------------------------------------­---



TAx_ISR ; CCR1/UART ISR: RXTXData Buffer holds UART Data.
;--------------------------------------------------------------------------­---



add.w #Bitime,&CCR1 ; Time to Next Bit
bit.w #CCIS1,&CCTL1 ; RX on ISCCIB?
jnz UART_RX ; Jump --> RX
UART_TX cmp.w #00h,&BitCnt ;
jne TX_Next ; Next bit?
bic.w #CCIE,&CCTL1 ; All Bits TX or RX,
Disable Int.
reti ;
TX_Next bic.w #OUTMOD_4,&CCTL1 ; TX Mark
rra.w &RXTXData ; LSB is shifted to carry
jc TX_Test ; Jump --> bit = 1
TX_Space bis.w #OUTMOD_4,&CCTL1 ; TX Space
TX_Test dec.w &BitCnt ; All bits sent (or
received)?
reti ;
;
UART_RX bit.w #CAP,&CCTL1 ; Compare mode for start
bit edge
jz RX_Bit ; Start bit edge?
RX_Edge bic.w #CAP,&CCTL1 ; Switch to Compare mode
add.w #Bitime_5,&CCR1 ; First databit 1.5 bits
from edge
reti ;
RX_Bit bit.w #SCCI,&CCTL1 ; Get bit waiting in
receive latch
rrc.b &RXTXData ; Store received bit
RX_Test dec.w &BitCnt ; All bits sent (or
received)?
jnz RX_Next ; Next bit?
;>>>>>>>>>> Decode of Received Byte Here
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
RX_Comp bic.w #CCIE,&CCTL1 ; All Bits RXed, Disable
Interrupt
mov.w #GIE,0(SP) ; Decode Byte= Active in
Mainloop
;>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

RX_Next reti ;
;
;--------------------------------------------------------------------------­---



; Interrupt Vectors Used MSP430x11x1
;--------------------------------------------------------------------------­---



ORG 0FFFEh ; MSP430 RESET Vector
DW RESET ;
ORG 0FFF0h ; Timer_A0 Vector
DW TAx_ISR ;
END