MK20DX256 >> Assembly
Button
參考資訊：
1. ds_pdf
2. pm_pdf
3. example
按鍵連接到PTC-2
Disable Watchdog
Port Clock
Enable Port
Port Direction
Port Input
main.s
.equiv GPIOC_BASE, 0x400ff080 .equiv GPIO_PDOR, 0x00 .equiv GPIO_PDIR, 0x10 .equiv GPIO_PDDR, 0x14 .equiv SIM_BASE, 0x40047000 .equiv SIM_SCGC5, 0x1038 .equiv WDOG_BASE, 0x40052000 .equiv WDOG_STCTRLH, 0x00 .equiv WDOG_UNLOCK, 0x0e .equiv PORTC_BASE, 0x4004b000 .equiv PORTC_PCR2, 0x08 .equiv PORTC_PCR5, 0x14 .thumb .cpu cortex-m4 .syntax unified .global _start .text .org 0x0000 _start: .word 0x20008000 .word reset .org 0x0100 .thumb_func reset: ldr r0, =WDOG_BASE ldr r1, =0xc520 strh r1, [r0, #WDOG_UNLOCK] ldr r1, =0xd928 strh r1, [r0, #WDOG_UNLOCK] ldr r1, =0x0000 strh r1, [r0, #WDOG_STCTRLH] ldr r0, =SIM_BASE + SIM_SCGC5 ldr r1, =(1 << 11) str r1, [r0] ldr r0, =PORTC_BASE ldr r1, =(1 << 8) str r1, [r0, #PORTC_PCR5] ldr r1, =(1 << 8) | (1 << 1) | (1 << 0) str r1, [r0, #PORTC_PCR2] ldr r0, =GPIOC_BASE ldr r1, =(1 << 5) str r1, [r0, #GPIO_PDDR] 0: ldr r1, [r0, #GPIO_PDIR] lsl r1, #3 eor r1, #0xff str r1, [r0, #GPIO_PDOR] b 0b .end
完成
