From 9da49fa5e3c1c87eead950b9d7335f566981f8aa Mon Sep 17 00:00:00 2001
From: Aadi Desai <21363892+supleed2@users.noreply.github.com>
Date: Sat, 10 Jun 2023 14:07:36 +0100
Subject: [PATCH] Add `can_init()` and `can_isr()`

---
 demo/can      |  4 ++++
 demo/can.cpp  | 22 ++++++++++++++++++++++
 demo/main.cpp | 14 ++++++++++++--
 3 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/demo/can b/demo/can
index 400166e..608dfa4 100644
--- a/demo/can
+++ b/demo/can
@@ -21,3 +21,7 @@ uint32_t can_mask_read(void);
 void can_mask_write(uint32_t value);
 
 can_frame can_read(void);
+
+void can_isr(void);
+
+void can_init(void);
diff --git a/demo/can.cpp b/demo/can.cpp
index 5d2f4ef..37ca739 100644
--- a/demo/can.cpp
+++ b/demo/can.cpp
@@ -1,6 +1,10 @@
 #include "can"
 #include <generated/csr.h>
+#include <irq.h>
 #include <stdint.h>
+#include <stdio.h>
+
+char *readstr(bool);
 
 #ifdef CSR_CAN_BASE
 uint32_t can_id_read(void) {
@@ -32,4 +36,22 @@ can_frame can_read(void) {
 	frame.data[7] = can_rcv_data7_read();
 	return frame;
 }
+
+void can_isr(void) {
+	can_ev_pending_frame_write(1);				// Should use `can_ev_pending_read()` and check which interrupt, but there is only 1
+	leds_out_write(leds_out_read() ^ 0xFF0000); // Toggle Red LED
+	can_frame frame = can_read();
+	printf("\033[F\033[F\33[2K\nCAN frame received, ID: 0x%03X, data: 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X\n",
+		   frame.id, frame.data[0], frame.data[1], frame.data[2], frame.data[3], frame.data[4], frame.data[5],
+		   frame.data[6], frame.data[7]); // Print CAN frame to UART
+	can_ev_enable_frame_write(1);		  // Re-enable event handler, same as in `can_init()`
+	printf("\e[92;1mStackSynth\e[0m> ");  // Print prompt to UART
+	readstr(true);						  // Print current user input (if any)
+}
+
+void can_init(void) {
+	irq_setmask(irq_getmask() | (1 << CAN_INTERRUPT)); // Enable CAN interrupt
+	can_ev_enable_frame_write(1);					   // Should be `can_ev_enable_frame_write(1)` but it is equivalent
+	printf("CAN INIT\n");							   // Print debug message to UART
+}
 #endif
diff --git a/demo/main.cpp b/demo/main.cpp
index d09d689..749f116 100644
--- a/demo/main.cpp
+++ b/demo/main.cpp
@@ -17,12 +17,14 @@
 /* Uart                                                                  */
 /*-----------------------------------------------------------------------*/
 
-static char *readstr(void) {
+char *readstr(bool print) {
 	char c[2];
 	static char s[64];
 	static unsigned int ptr = 0;
 
-	if (readchar_nonblock()) {
+	if (print) {
+		fputs(s, stdout);
+	} else if (readchar_nonblock()) {
 		c[0] = getchar();
 		c[1] = 0;
 		switch (c[0]) {
@@ -54,6 +56,10 @@ static char *readstr(void) {
 	return NULL;
 }
 
+static char *readstr(void) {
+	return readstr(false);
+}
+
 static char *get_token(char **str) {
 	char *c, *d;
 
@@ -439,17 +445,21 @@ static void console_service(void) {
 	prompt();
 }
 
+void isr(void);
+
 int main(void) {
 #ifdef CONFIG_CPU_HAS_INTERRUPT
 	irq_setmask(0);
 	irq_setie(1);
 #endif
 	uart_init();
+	can_init();
 
 	help();
 	prompt();
 
 	while (1) {
+		isr();
 		console_service();
 	}
 }