From b1206aaa1f6bc4a04509149024402dea9da12e27 Mon Sep 17 00:00:00 2001
From: xengineering <me@xengineering.eu>
Date: Thu, 30 May 2024 22:45:41 +0200
Subject: firmware: Implement send_frame()
This transmits a frame via the Serial Line Internet Protocol (SLIP).
---
firmware/src/main.c | 33 ++++++++++++++++++++++++++++++---
1 file changed, 30 insertions(+), 3 deletions(-)
(limited to 'firmware/src')
diff --git a/firmware/src/main.c b/firmware/src/main.c
index a9721ef..c8cddb2 100644
--- a/firmware/src/main.c
+++ b/firmware/src/main.c
@@ -1,13 +1,38 @@
#include <stdbool.h>
+#include <stdint.h>
-#include <zephyr/kernel.h>
#include <zephyr/device.h>
#include <zephyr/drivers/uart.h>
+#include <zephyr/kernel.h>
+#include <zephyr/sys/util.h>
#define UART_DEVICE_NODE DT_CHOSEN(zephyr_shell_uart)
static const struct device *const uart_dev = DEVICE_DT_GET(UART_DEVICE_NODE);
-#define SLIP_END 0xC0
+#define SLIP_END 0xC0
+#define SLIP_ESC 0xDB
+#define SLIP_ESC_END 0xDC
+#define SLIP_ESC_ESC 0xDD
+
+void send_frame(uint8_t *buffer, size_t len) {
+ for (size_t i = 0; i < len; i++) {
+ uint8_t octet = *(buffer + i);
+ switch (octet) {
+ case SLIP_END:
+ uart_poll_out(uart_dev, SLIP_ESC);
+ uart_poll_out(uart_dev, SLIP_ESC_END);
+ break;
+ case SLIP_ESC:
+ uart_poll_out(uart_dev, SLIP_ESC);
+ uart_poll_out(uart_dev, SLIP_ESC_ESC);
+ break;
+ default:
+ uart_poll_out(uart_dev, octet);
+ break;
+ }
+ }
+ uart_poll_out(uart_dev, SLIP_END);
+}
int main(void)
{
@@ -16,9 +41,11 @@ int main(void)
return 0;
}
+ uint8_t frame[] = {0xDE, 0xAD};
+
while (true) {
k_sleep(K_MSEC(1000));
- uart_poll_out(uart_dev, SLIP_END);
+ send_frame(frame, ARRAY_SIZE(frame));
}
return 0;
--
cgit v1.2.3-70-g09d2