44 lines
674 B
ArmAsm
44 lines
674 B
ArmAsm
.syntax unified
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.cpu cortex-m3
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.thumb
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.section .text
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.global vectors
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vectors:
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.align 2
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.word 0
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.word _start
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.thumb_func
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.global _start
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_start:
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/* enable port C clock */
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ldr r0, =0x40021000
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ldr r1, [r0, #0x18]
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mov r2, #5
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orr r1, r2
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str r1, [r0, #0x18]
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/*
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* enable output mode at a max of 2 MHz.
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* note that the default is a general purpose output push-pull,
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* which is what it should be.
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*/
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ldr r0, =0x40011000
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ldr r1, [r0, #0x04]
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mov r2, #0x02
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lsl r2, #0x14
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orr r1, r2
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str r1, [r0, #0x04]
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/* write LED pin (PC13) */
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ldr r0, =0x40011000
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ldr r1, [r0, #0x10]
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mov r2, #0x01
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lsl r2, #0x0d
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lsl r2, #0x10
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orr r1, r2
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str r1, [r0, #0x10]
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hang: bl .
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