微處理器 - NXP LPC2103 - Assembly - Timer1

參考資料：
https://www.keil.com/dd/docs/datashts/philips/user_manual_lpc2101_2102_2103.pdf

暫存器





main.s

    .equ IODIR,        0xe0028008
    .equ IOCLR,        0xe002800c
    .equ IOSET,        0xe0028004
    .equ PINSEL0,      0xe002c000
    .equ EXTINT,       0xe01fc140
    .equ VICIntEnable, 0xfffff010
    .equ T1PR,         0xe000800c
    .equ T1MR0,        0xe0008018
    .equ T1MCR,        0xe0008014
    .equ T1TCR,        0xe0008004
    .equ T1CTCR,       0xe0008070
    .equ T1IR,         0xe0008000

    .data
blink: .dcb 1

    .text
    .align 2
    .global _start
_start:    b reset
_undef:    b .
_swi:      b .
_pabort:   b .
_dabort:   b .
_reserved: b .
_irq:      b irq_handler
_fiq:      b .
    
reset:
    mrs r0, cpsr
    bic r0, #0x80
    msr cpsr_c, r0

    ldr r0, =T1PR
    ldr r1, =0x63
    str r1, [r0]

    ldr r0, =T1MR0
    ldr r1, =5000
    str r1, [r0]

    ldr r0, =T1MCR
    ldr r1, [r0]
    orr r1, #0x03
    str r1, [r0]

    ldr r0, =T1TCR
    ldr r1, =0x02
    str r1, [r0]

    ldr r0, =T1TCR
    ldr r1, =0x01
    str r1, [r0]

    ldr r0, =VICIntEnable
    ldr r1, =(1 << 5)
    str r1, [r0]

    ldr r0, =IODIR
    ldr r1, =(1 << 22)
    str r1, [r0]

    ldr r0, =IOCLR
    ldr r1, =(1 << 22)
    str r1, [r0]

    ldr r0, =blink
    ldr r1, =0x00
    str r1, [r0]
    b .
 
irq_handler:
    ldr r0, =blink
    ldr r1, [r0]
    cmp r1, #0x00
    beq 1f
    ldr r0, =IOSET
    ldr r1, =(1 << 22)
    str r1, [r0]
    b 2f
1:
    ldr r0, =IOCLR
    ldr r1, =(1 << 22)
    str r1, [r0]
2:
    ldr r0, =blink
    ldr r1, [r0]
    eor r1, #0xff
    str r1, [r0]

    ldr r0, =T1IR
    ldr r1, =0x01
    str r1, [r0]
    subs pc, lr, #4
    .end

完成