Proper timing for leds using systick and interrupts.HEADmain

This means a new "frame" is written every 30th of a second.

1 files changed, 19 insertions, 100 deletions

diff --git a/src/main.c b/src/main.c
index c80ab30..33728ea 100644
--- a/src/main.c
+++ b/src/main.c
@@ -60,92 +60,14 @@ uint32_t collatz(uint32_t n)
   return c;
 }
 
-static void print_reg(uint32_t reg)
-{
-  // 0x40001008
-  printf("register @0x%08x = 0x%08x\n", reg, *(uint32_t*)reg);
-}
-
-static void set_system_clock_6Mhz(void)
-{
-  print_reg(0x40001008);
-  printf("Setting system clock to 6Mhz...\n");
-  clock_cfg_t clk_cfg = {0};
-  clk_cfg.sel = CLOCK_SELECTION_HSE;
-  clk_cfg.pll_clock_divisor = 5;
-  if (set_system_clock(&clk_cfg)) {
-    printf("Failed to set system clock.\n");
-  }
-  print_reg(0x40001008);
-  printf("Done\n");
-}
-
-static void set_system_clock_3Mhz(void)
-{
-  print_reg(0x40001008);
-  printf("Setting system clock to 3Mhz...\n");
-  clock_cfg_t clk_cfg = {0};
-  clk_cfg.sel = CLOCK_SELECTION_HSE;
-  clk_cfg.pll_clock_divisor = 10;
-  if (set_system_clock(&clk_cfg)) {
-    printf("Failed to set system clock.\n");
-  }
-  print_reg(0x40001008);
-  printf("Done\n");
-}
-
 static void set_system_clock_60Mhz(void)
 {
-  print_reg(0x40001008);
-  printf("Setting system clock to 60Mhz...\n");
   clock_cfg_t clk_cfg = {0};
   clk_cfg.sel = CLOCK_SELECTION_PLL;
   clk_cfg.pll_clock_divisor = 8;
   if (set_system_clock(&clk_cfg)) {
     printf("Failed to set system clock.\n");
-  }
-  print_reg(0x40001008);
-  printf("Done\n");
-}
-
-static void set_system_clock_30Mhz(void)
-{
-  print_reg(0x40001008);
-  printf("Setting system clock to 30Mhz...\n");
-  clock_cfg_t clk_cfg = {0};
-  clk_cfg.sel = CLOCK_SELECTION_PLL;
-  clk_cfg.pll_clock_divisor = 16;
-  if (set_system_clock(&clk_cfg)) {
-    printf("Failed to set system clock.\n");
-  }
-  print_reg(0x40001008);
-  printf("Done\n");
-}
-
-static void set_system_clock_32kHz()
-{
-  print_reg(0x40001008);
-  printf("Setting system clock to 32kHz...\n");
-  clock_cfg_t clk_cfg = {0};
-  clk_cfg.sel = CLOCK_SELECTION_LSE;
-  if (set_system_clock(&clk_cfg)) {
-    printf("Failed to set system clock.\n");
-  }
-}
-
-static void basic_delay()
-{
-  set_sysled(1);
-  for (int i = 0; i < 30000; ++i) {
-    asm volatile("");
-  }
-  set_sysled(0);
-}
-
-static void fast_delay()
-{
-  for (int i = 0; i < 1000; ++i) {
-    asm volatile("");
+    panic(0xff);
   }
 }
 
@@ -185,12 +107,6 @@ rgb_t get_rgb(uint32_t time, size_t x)
   r = 0xff;
   g = byte_scale(byte_sin(time8 * TIME_STEP + x * 2), 0x90);
   b = byte_scale(byte_sin(time8 * TIME_STEP + x * 2), 0x20);
-  // r = byte_scale(byte_sin(time8 * TIME_STEP + x * 2), AS_BYTE(0.25)) +
-  //     AS_BYTE(0.75);
-  // b = 0x40;
-  // g = byte_scale(
-  //         0xff - byte_sin(time8 * TIME_STEP + x * 7 + 0x80), AS_BYTE(0.5)) +
-  //     AS_BYTE(0.5);
 
   rgb_t color;
   color.color = 0;
@@ -200,6 +116,15 @@ rgb_t get_rgb(uint32_t time, size_t x)
   return color;
 }
 
+
+static volatile uint32_t time = 0;
+static volatile int spin_lock = 0;
+
+On_SysTick() {
+  time ++;
+  spin_lock = 0;
+}
+
 /*
  * Main routine. This is called on_reset once everything else has been set up.
  */
@@ -211,12 +136,7 @@ int main(void)
   PFIC->interrupt_priority_threshold = 0x10;
   PFIC->interrupt_enable |= IRQ_SysTick;
 
-  printf(
-      "PFIC enable status 1: %08x\n",
-      (uint32_t)(PFIC->interrupt_enable_status));
-
   set_system_clock_60Mhz();
-
   set_systick(250000);
 
   enable_sysled();
@@ -228,29 +148,28 @@ int main(void)
   ws_buf.byte_order = BYTE_ORDER_GRB;
 
   rgb_t color;
-  uint32_t time = 0;
 
   GPIO_PORT.dir.set(GPIO_PORT_B, DIR_OUT, 7);
+
   while (1) {
-    // Fill the buffer with calculated rgb colors.
     ws_buf.cur = 0;
     for (int i = 0; i < N_LEDS; ++i) {
       rgb_t rgb = get_rgb(time, i);
       write_rgb(&ws_buf, rgb);
     }
 
-    time++;
-    GPIO_PORT.out.set(GPIO_PORT_B, ON, 7);
-    for (int i = 0; i < N_DMA_XFER; ++i) {
+    while (spin_lock) {
+      set_sysled(1); // Setting the sysled helps me to measure down time.
+    }
+    set_sysled(0);
+
+    spin_lock = 1;
+
+    for (int j = 0; j < N_DMA_XFER; ++ j) {
       wait_for_dma();
       start_dma(&ws_buf);
     }
-    basic_delay();
   }
 
   return 0;
 }
-
-On_SysTick() {
-  printf("Systick BOI!\n");
-}