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Copy pathgpio.S
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gpio.S
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.include "lpc4357.inc"
.equ DIR_0, 0x2000
.equ DIR_1, 0x2004
.equ DIR_2, 0x2008
.equ DIR_3, 0x200C
.equ DIR_4, 0x2010
.equ DIR_5, 0x2014
.equ DIR_6, 0x2018
.equ DIR_7, 0x201C
.equ DIR_SIZE, 0x4
.global _gpio_set_dir_out
.type _gpio_set_dir_out, %function
_gpio_set_dir_out: @ r1 = port, r2 = pin
push {r4, r5, r6}
ldr r4, =LPC_GPIO_PORT_BASE
mov r6, #DIR_SIZE
mul r1, r6
ldr r6, =DIR_0
add r1, r6
add r4, r1
ldr r5, [r4]
mov r6, #1
lsl r6, r6, r2
orr r5, r6 @ port |= 1 << pin
str r5, [r4]
pop {r4, r5, r6}
bx lr
.size _gpio_set_dir_out, .-_gpio_set_dir_out
.global _gpio_set_dir_in
.type _gpio_set_dir_in, %function
_gpio_set_dir_in: @ r1 = port, r2 = pin
push {r4, r5, r6}
ldr r4, =LPC_GPIO_PORT_BASE
mov r6, #DIR_SIZE
mul r1, r6
ldr r6, =DIR_0
add r1, r6
add r4, r1
ldr r5, [r4]
mov r6, #1
lsl r6, r6, r2
bic r5, r6 @ port &= ~(1 << pin)
str r5, [r4]
pop {r4, r5, r6}
bx lr
.size _gpio_set_dir_in, .-_gpio_set_dir_in
.equ B_0, 0x0000
.equ B_1, 0x0020
.equ B_SIZE, 0x20
.global _gpio_set
.type _gpio_set, %function
_gpio_set: @ r1 = port, r2 = pin, r3 = val
push {r4, r6}
ldr r4, =LPC_GPIO_PORT_BASE
mov r6, #B_SIZE
mul r1, r6
ldr r6, =B_0
add r1, r6
add r1, r2
add r4, r1
strb r3, [r4]
pop {r4, r6}
bx lr
.size _gpio_set, .-_gpio_set