Files
eink-dairy/keyboard_stdio.cpp

47 lines
1.2 KiB
C++

#include "keyboard_stdio.h"
#include "pico/stdio/driver.h"
#include "pico/sync.h"
#define KBD_BUF_SIZE 128
// Circular buffer for keyboard input
static char kbd_buf[KBD_BUF_SIZE];
static volatile int write_idx = 0;
static volatile int read_idx = 0;
static critical_section_t kbd_crit;
void keyboard_stdio_push_char(char c) {
critical_section_enter_blocking(&kbd_crit);
int next_write = (write_idx + 1) % KBD_BUF_SIZE;
if (next_write != read_idx) { // Only write if not full
kbd_buf[write_idx] = c;
write_idx = next_write;
}
critical_section_exit(&kbd_crit);
}
static int keyboard_in_chars(char *buf, int len) {
int count = 0;
critical_section_enter_blocking(&kbd_crit);
while (count < len && read_idx != write_idx) {
buf[count++] = kbd_buf[read_idx];
read_idx = (read_idx + 1) % KBD_BUF_SIZE;
}
critical_section_exit(&kbd_crit);
return count > 0 ? count : PICO_ERROR_NO_DATA;
}
static stdio_driver_t kbd_driver = {
.out_chars = NULL,
.out_flush = NULL,
.in_chars = keyboard_in_chars,
#if PICO_STDIO_ENABLE_CRLF_SUPPORT
.crlf_enabled = false
#endif
};
void keyboard_stdio_init(void) {
critical_section_init(&kbd_crit);
stdio_set_driver_enabled(&kbd_driver, true);
}