77 lines
1.6 KiB
ArmAsm
77 lines
1.6 KiB
ArmAsm
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.file "main.S"
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#include <msp430g2553.h>
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#define PC r0
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#define SP r1
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#define SR r2
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;; .text is the name of the section, it is a hint for the linker to
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;; allocate the section
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;; ax: a means allocatable by linker, x means executable
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;; @progbits is a hint for the linker to allocate this section into
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;; program memory (flash)
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.section ".text","ax",@progbits
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_start:
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;; disable watchdog
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mov.w #WDTPW|WDTHOLD,&WDTCTL
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;; configure clock system to the highest frequency
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mov.b #DCO0|DCO1|DCO2,&DCOCTL
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mov.b #XT2OFF|RSEL0|RSEL1|RSEL2|RSEL3,&BCSCTL1
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mov.b #0,&BCSCTL2
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mov.b #0,&BCSCTL3
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;; initialize stack pointer with value from linker
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mov.w #__stack, SP
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init:
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;; configuration of GPIO Port1, use Bit6 as TA0.1
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mov.b #BIT6,&P1DIR
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mov.b #BIT6,&P1SEL
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;; timer configuration
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;; configure and stop timer
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;; cycle time is 56.25ns
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mov.w #ID_0|MC_0|TACLR|TASSEL_2,&TACTL
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;; 2.0us
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mov.w #45,&TACCR0
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;; a bit less
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mov.w #16,&TACCR1
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;; configure output mode for TA0.1
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; mov.w #CCIE,&TACCTL0
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; mov.w #CCIE,&TACCTL1
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mov.w #OUTMOD_7,&TACCTL1
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;; start timer in up mode
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bis.w #MC0,&TACTL
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;; enable interrupts
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eint
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mainloop:
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jmp mainloop
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; --- timer isr ---
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;timer0_a0_isr:
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; mov.b #BIT0,&P1OUT
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; reti
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;timer0_a1_isr:
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; mov.b #0,&P1OUT
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; reti
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; --- interrupt vectors ---
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; .section "__interrupt_vector_9","ax",@progbits
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; .word timer0_a1_isr
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; .section "__interrupt_vector_10","ax",@progbits
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; .word timer0_a0_isr
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;; .resetvec comes from linker
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.section ".resetvec","ax",@progbits
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.word _start
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.end
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