1 files changed, 75 insertions, 0 deletions
diff --git a/stm32/app/ticker.c b/stm32/app/ticker.c
new file mode 100644
index 0000000..eb7dfe5
--- /dev/null
+++ b/stm32/app/ticker.c
@@ -0,0 +1,75 @@
+#include "project.h"
+
+
+
+
+static volatile uint32_t ticks;
+static volatile uint32_t delay_ms_count;
+static uint32_t scale = 7;
+
+
+void
+delay_us (uint32_t d)
+{
+  d *= scale;
+
+  while (d--)
+    __asm__ ("nop");
+}
+
+
+void
+sys_tick_handler (void)
+{
+  if (delay_ms_count)
+    delay_ms_count--;
+
+
+  led_tick();
+  oled1_ticker();
+  oled2_ticker();
+  gauge_ticker();
+
+  ticks++;
+}
+
+
+void
+delay_ms (uint32_t d)
+{
+  delay_ms_count = MS_TO_TICKS (d);
+
+  while (delay_ms_count);
+}
+
+
+void
+ticker_init (void)
+{
+  uint32_t v, w;
+
+  /*Start periodic timer */
+
+  systick_set_clocksource (STK_CSR_CLKSOURCE_AHB_DIV8);
+  /* 72MHz / 8 = > 9Mhz */
+  systick_set_reload (TICK_DIV);
+  systick_interrupt_enable();
+  systick_counter_enable();
+
+  /*Calibrate the delay loop */
+
+
+  do {
+    scale--;
+    v = ticks;
+
+    while (v == ticks);
+
+    delay_us (TICKS_TO_US (1));
+    w = ticks;
+    v++;
+    w -= v;
+  } while (w);
+
+
+}