Get a good, basic framework for ISRs and properly handle the data sections.

1 files changed, 20 insertions, 54 deletions

diff --git a/src/blinky.c b/src/blinky.c
index d8a29bd..9f89238 100644
--- a/src/blinky.c
+++ b/src/blinky.c
@@ -1,50 +1,19 @@
 #include <stdint.h>
 
+#include "isr_vector.h"
 #include "ch573/gpio.h"
 
 #define GPIO_PORT_A ch573_gpio__gpio_port_a
 #define GPIO_PORT CH573_GPIO__GPIO_PORT_T_INTF
 
-static void start(void);
-
-/*
- * Function (or really pointer to code) for the reset interrupt handler.
- */
-void on_reset(void);
-
 /*
  * Function which delays for a bit.
  */
 void delay(void);
 
-/* Type def to a void function to make things mor ereadable. */
-typedef void (*isr_routine)(void);
-
-/** The ISR Vector structure. This is linked to starting at address 0. */
-// __attribute((__section__(".isr_vector"))) volatile struct {
-//   // What NULL points to. nothing useful.
-//   uint32_t reserved__;
-//   // Called when the device boots or reset is pressed.
-//   isr_routine reset_cb;
-//   isr_routine nmi_cb;
-//   isr_routine exc_cb;
-// } isr_vectors = {.reset_cb = on_reset};
-
-/*
- * The reset callback.This has to be a naked function because the stack pointer
- * may not be initialized!!.
- */
-__attribute((naked)) void on_reset(void)
-{
-  // Set up the stack pointer to point to the end of SRAM.
-  asm volatile(
-      "li	sp,0x20008000\n"
-      "addi	sp,sp,-4\n"
-      "jalr %0\n"
-      "spin:\n"
-      "j spin\n"
-      :
-      : "r"(start));
+void main(void);
+IRQ(irq_on_systick) {
+  main();
 }
 
 uint32_t collatz(uint32_t n)
@@ -77,38 +46,35 @@ void blink_n(int n)
 
 void delay(void)
 {
-  for (volatile uint32_t i = 0; i < 10000; ++i);
+  for (volatile uint32_t i = 0; i < 10000; ++i) {
+    asm volatile("");
+  }
 }
 
+volatile uint32_t deadbeef = 0xdeadbeef;
+
+// Memory-mapped address of the data values in flash.
+extern uint32_t DATA_VALUES_IN_FLASH;
+
+// Where the data is located in sram.
+extern uint32_t DATA_SEGMENT_START;
+extern uint32_t DATA_SEGMENT_STOP;
+
 /* Main routine. This is called on_reset once everything else has been set up.
  */
-static void start(void)
+void main(void)
 {
   GPIO_PORT.dir.set(GPIO_PORT_A, DIR_OUT, 8);
   GPIO_PORT.pd_drv.set(GPIO_PORT_A, PD_DRV_OPEN_DRAIN, 8);
 
   for (;;) {
-    GPIO_PORT.out.set(GPIO_PORT_A, ON, 8);
+    if (deadbeef == 0xdeadbeef) {
+      GPIO_PORT.out.set(GPIO_PORT_A, ON, 8);
+    }
     delay();
     delay();
     delay();
     GPIO_PORT.out.set(GPIO_PORT_A, OFF, 8);
     delay();
   }
-
-  // uint32_t i;
-  // for (i = 1;; ++i) {
-  //   uint32_t c = collatz(i);
-  //   blink_n(c);
-
-  //   delay();
-  //   delay();
-  //   delay();
-  //   delay();
-  //   delay();
-  //   delay();
-  //   delay();
-  //   delay();
-  //   delay();
-  // }
 }