微處理器 - Nuvoton NUC977 - Assembly - UART0


參考資訊：
https://github.com/OpenNuvoton/NUC970_NonOS_BSP

GPIO Alternative Function



UART0 TX Buffer


n,8,1


115200bps


main.s

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    .equ CLK_PCLKEN0,  (0xb0000200 + 0x18)
    .equ SYS_GPE_MFPL, (0xb0000000 + 0x90)
    .equ UA0_THR,      (0xb8000000 + 0x00)
    .equ UA0_LCR,      (0xb8000000 + 0x0c)
    .equ UA0_BAUD,     (0xb8000000 + 0x24)
 
    .text
    .align 2
    .global _start
_start:    b reset
_undef:    b .
_swi:      b .
_pabort:   b .
_dabort:   b .
_reserved: b .
_irq:      b .
_fiq:      b .
  
reset:
    ldr r0, =CLK_PCLKEN0
    ldr r1, [r0]
    orr r1, #(1 << 16)
    str r1, [r0]
 
    ldr r0, =SYS_GPE_MFPL
    ldr r1, [r0]
    and r1, #0xfffffff0
    orr r1, #0x00000009
    str r1, [r0]
 
    /* 115200bps */
    ldr r0, =UA0_BAUD
    ldr r1, =0x30000066
    str r1, [r0]
  
loop:
    ldr r0, =UA0_THR
    ldr r1, =0x55
    str r1, [r0]
    ldr r4, =1000000
1:
    subs r4, r4, #1
    bne 1b
    b loop
    .end

完成