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mini_uart.c
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/
mini_uart.c
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#include "gpio.h"
#include "utils.h"
#include "peripherals/aux.h"
#include "mini_uart.h"
#define TXD 14
#define RXD 15
void uart_init() {
gpio_pin_set_func(TXD, GFAlt5);
gpio_pin_set_func(RXD, GFAlt5);
gpio_pin_enable(TXD);
gpio_pin_enable(RXD);
REGS_AUX->enables = 1;
REGS_AUX->mu_control = 0;
REGS_AUX->mu_ier = 0;
REGS_AUX->mu_lcr = 3;
REGS_AUX->mu_mcr = 0;
REGS_AUX->mu_baud_rate = 541; // = 115200 @ 500 Mhz
REGS_AUX->mu_control = 3;
uart_send('\r');
uart_send('\n');
uart_send('\n');
}
void uart_send(char c) {
while(!(REGS_AUX->mu_lsr & 0x20));
REGS_AUX->mu_io = c;
}
char uart_recv() {
while(!(REGS_AUX->mu_lsr & 1));
return REGS_AUX->mu_io & 0xFF;
}
void uart_send_string(char *str) {
while(*str) {
if (*str == '\n') {
uart_send('\r');
}
uart_send(*str);
str++;
}
}