27 lines
748 B
ArmAsm
27 lines
748 B
ArmAsm
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.syntax unified
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.cpu cortex-m0plus
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.thumb
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#include "pico/asm_helper.S"
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// This macro tells the pico runtime to call __wakeup_gpio_latch very early in boot
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__pre_init __wakeup_gpio_latch, 00001
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.section .data.wakeup_gpio_latch
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.global wakeup_gpio_state
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.align 4
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wakeup_gpio_state:
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.word 0x00000000
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.section .text
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.thumb_func
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__wakeup_gpio_latch:
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// Read GPIO state for front buttons and store
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movs r3, 0xd0 // Load 0xd0 into r3
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lsls r3, r3, 24 // Shift left 24 to get 0xd0000000
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ldr r1, [r3, 4] // Load GPIO state (0xd0000004) into r1
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ldr r2, =wakeup_gpio_state // Load output var addr into r2
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str r1, [r2] // Store r1 to r2
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bx lr // Return
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