TIMER A Cont..

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By Jackson Taylor

1 second timer in up mode
using internal DCO (0.999908182 seconds)
Here calculations are done assuming DCO = 1.1MHz
Time  = ((1100+1)/1.1MHz)*999 = 0.999908182  seconds…!
.include “msp430g2x31.inc”
org 0xf800                 
      mov #(WDTPW|WDTHOLD), &WDTCTL
      mov #0x280, SP
      mov.b #0x41,&P1DIR
      clr.b P1OUT  
      clr R5
      mov #(TASSEL_2|MC_1|ID_0|TAIE), &TACTL
      mov #1100, &TACCR0
      eint      
jimmy:  jmp jimmy
TAISR:     
      inc R5     
      cmp #999, R5
      jne exit
      xor.b #0x41,&P1OUT  
      clr R5 
exit:
      bic #1, &TACTL
      reti                          
org     0FFF0h                 
dw      TAISR    
org     0FFFEh                 
dw     0xf800    
Timer A — high speed blinking using up/down mode
Time  = (65000*2)+1/1.1MHz = 0.118182727
.include “msp430g2x31.inc”
org 0xf800                 
      mov #(WDTPW|WDTHOLD), &WDTCTL
      mov #0x280, SP
      mov.b #0x41,&P1DIR
      mov.b #0x41,P1OUT  
      mov #(TASSEL_2|MC_3|TAIE), &TACTL
      mov #65000, &TACCR0
      eint
jimmyloop:
      jmp jimmyloop          
jimmyisr:
      bic #1,&TACTL
      xor.b #41h, &P1OUT
      reti
ORG     0FFF0h                 
DW      jimmyisr
ORG     0FFFEh                 
DW      0xf800
Timer A — high speed blinking using up mode & CCIFG
.include “msp430g2x31.inc”
org f800h                 
      mov #(WDTPW|WDTHOLD), &WDTCTL
      mov #0x280, SP
      mov.b #0x41,&P1DIR
      mov.b #0x41,P1OUT  
      mov #(TASSEL_2|MC_1), &TACTL
      mov #CCIE, &TACCTL0
      mov #65000, &TACCR0
      eint
jimmyloop:
      jmp jimmyloop          
jimmyisr:
      xor.b #41h, &P1OUT
      reti
ORG     0FFF2h                 
DW      jimmyisr
ORG     0FFFEh                 
DW      0xf800 
Timer A — high speed blinking using up/down mode & CCIFG
.include “msp430g2x31.inc”
org 0xf800                 
      mov #(WDTPW|WDTHOLD), &WDTCTL
      mov #0x280, SP
      mov.b #0x41,&P1DIR
      mov.b #0x41,P1OUT  
      mov #(TASSEL_2|MC_3), &TACTL
      mov #CCIE, &TACCTL0
      mov #65000, &TACCR0
      eint
jimmyloop:
      jmp jimmyloop          
jimmyisr:
      xor.b #41h, &P1OUT
      reti
ORG     0FFF2h                 
DW      jimmyisr
ORG     0FFFEh                 
DW      0xf800