UARTのループバックをRP2350で動かす - htkymtks

UARTのループバックをRP2350で動かす

from Raspberry Pi Pico2でCPU実験のレイトレを動かしたい

code:diff

diff --git a/stub.c b/stub.c

index 6c1d5c0..a4637d4 100644

--- a/stub.c

+++ b/stub.c

@@ -41,6 +41,8 @@ typedef struct {

#define UART0 ((UART *)UART0_BASE)

#define UART_CTRL_TX_EN (1u << 0)

#define UART_CTRL_RX_EN (1u << 1)

+#define UART_STATE_TXFULL (1u << 0)

+#define UART_STATE_RXFULL (1u << 1)

extern void min_caml_start(char *, char *);

@@ -55,11 +57,17 @@ static void uart_init(void) {

}

static void uart_putc(char c) {

- while (UART0->STATE & (1u << 0)) { // TXFULL

+ while (UART0->STATE & UART_STATE_TXFULL) {

}

UART0->DATA = (uint32_t)c;

}

+static char uart_getc(void) {

+ while (!(UART0->STATE & UART_STATE_RXFULL)) {

+ }

+ return (char)(UART0->DATA & 0xff);

+}

+

static void uart_puts(const char *s) {

while (*s) {

if (*s == '\n') {

@@ -136,5 +144,12 @@ int main(void) {

min_caml_start((char *)min_caml_stack, (char *)min_caml_heap);

while (1) {

+ char c = uart_getc();

+

+ if (c == '\r') {

+ uart_putc('\n');

+ }

+

+ uart_putc(c);

}

}