Switch from internal clock to crystal + button

3 files changed, 80 insertions, 36 deletions

diff --git a/src/display.c b/src/display.c
new file mode 100644
index 0000000..5f2d7f3
--- /dev/null
+++ b/src/display.c
@@ -0,0 +1,41 @@
+#include <avr/io.h>
+#include <stdint.h>
+#include <util/delay.h>
+
+#include "display.h"
+
+// "_gfedcba"
+// Reversed because a-g is mapped to pa0-6. (pa7 is decimal)
+// Complemented because display is common anode
+const uint32_t digit_masks[] = {
+    0b01000000, 0b01111001, 0b00100100, 0b00110000, 0b00011001,
+    0b00010010, 0b00000010, 0b01111000, 0b00000000, 0b00010000,
+};
+
+void write_digit(uint8_t digit) {
+  if (digit > 9 || digit < 0)
+    return;
+  PORTA = digit_masks[digit];
+}
+
+void write_time(uint16_t hour, uint16_t minute) {
+  uint8_t minute_digit1 = minute % 10;
+  uint8_t minute_digit2 = minute / 10;
+  // unsigned short hour_digit1 = hour % 10;
+  // unsigned short hour_digit2 = hour / 10;
+
+#ifdef STUBBED
+  printf("\r:: %d %d", minute_digit2, minute_digit1);
+  fflush(stdout);
+#endif
+
+  write_digit(minute_digit1);
+  PORTA |= (1 << PA7);
+  _delay_ms(10);
+  PORTA &= ~(1 << PA7);
+
+  write_digit(minute_digit2);
+  PORTB |= (1 << PB2);
+  _delay_ms(10);
+  PORTB &= ~(1 << PB2);
+}
diff --git a/src/display.h b/src/display.h
new file mode 100644
index 0000000..a2bbc79
--- /dev/null
+++ b/src/display.h
@@ -0,0 +1,9 @@
+#ifndef _LOADED_DISPLAY
+#define _LOADED_DISPLAY
+#include <stdint.h>
+
+void write_digit(uint8_t digit);
+
+void write_time(uint16_t hour, uint16_t minute);
+
+#endif
diff --git a/src/main.c b/src/main.c
index c1dc647..fd4a091 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,51 +1,45 @@
 #include <avr/io.h>
+#include <avr/fuse.h>
 #include <stdint.h>
 #include <util/delay.h>
 
-// a b c d e f g decimal
-// Reversed because a-g is mapped to pa0-6. (pa7 is decimal)
-// Complemented because display is common anode
-const uint32_t digits[] = {
-    0b01000000, 0b01111001, 0b00100100, 0b00110000, 0b00011001,
-    0b00010010, 0b00000010, 0b01111000, 0b00000000, 0b00010000,
+#include "display.h"
+
+// Config for attiny84a + 32KHz crystal osc taken from https://github.com/ingepnet/breadboardwatch/blob/master/Makefile#L26
+FUSES = {
+  .low = 0xe6,
+  .high = 0xd7,
+  .extended = 0xff,
 };
 
-void write_digit(uint8_t digit) {
-  if (digit > 9 || digit < 0)
-    return;
-  PORTA = digits[digit];
+void setup_output(void) {
+  DDRA |= 0b11111111;
+  DDRB |= 0b11111111;
 }
 
-void write_time(uint16_t hour, uint16_t minute) {
-  uint8_t minute_digit1 = minute % 10;
-  uint8_t minute_digit2 = minute / 10;
-  // unsigned short hour_digit1 = hour % 10;
-  // unsigned short hour_digit2 = hour / 10;
+int main(void) {
+  uint32_t count = 0;
+  uint8_t is_button_on = 0;
 
-#ifdef STUBBED
-  printf("\r:: %d %d", minute_digit2, minute_digit1);
-  fflush(stdout);
-#endif
+  while (1) {
+    DDRB &= ~(1 << PB2);
+    is_button_on = (PINB & (1 << PB2)) > 0;
 
-  write_digit(minute_digit1);
-  PORTA |= (1 << PA7);
-  _delay_ms(10);
-  PORTA &= ~(1 << PA7);
+    if (is_button_on) {
+      _delay_ms(30);
+      is_button_on = (PINB & (1 << PB2)) > 0;
+      if (is_button_on) {
+        setup_output();
+        PORTA |= 0b10000000;
+        _delay_ms(500);
+        continue;
+      }
+    }
 
-  write_digit(minute_digit2);
-  PORTB |= (1 << PB2);
-  _delay_ms(10);
-  PORTB &= ~(1 << PB2);
-}
+    setup_output();
+    write_time(0, (count / 20) % 60);
 
-int main(void) {
-  DDRA |= 0b11111111;
-  DDRB |= (1 << PB2);
-
-  uint32_t i = 0;
-  while (1) {
-    write_time(0, (i / 20) % 60);
-    i = (i + 1) % 100000;
+    count = (count + 1) % 100000;
   }
   return 0;
 }