PWM

// file: rcc.s .syntax unified .thumb .include "src/periph_regs.inc" .text .align 2 .global rcc_gpio_enable .thumb_func .type rcc_gpio_enable, %function rcc_gpio_enable: mov r3,#4 cmp r0,r3 bgt skip_enable ldr r3,=RCC_BASE ldr r1,[r3, #RCC_AHB1ENR] mov r2,#1 lsl r2,r0 orr r1,r2 str r1,[r3, RCC_AHB1ENR] skip_enable: bx lr .end