Measure vcc.

1 files changed, 37 insertions, 0 deletions

diff --git a/batchk/main.c b/batchk/main.c
new file mode 100644
index 0000000..a925aa1
--- /dev/null
+++ b/batchk/main.c
@@ -0,0 +1,37 @@
+#include <stdlib.h>
+
+#include <avr/io.h>
+#include <util/delay.h>
+
+#include "uart.h"
+
+int main(void)
+{
+	char s[6];
+	unsigned long v;
+
+	uart_init();
+
+	ADMUX |= (1 << REFS0);                               /* AVCC as reference  */
+	ADMUX |= (1 << MUX3) | (1 << MUX2) | (1 << MUX1);    /* measure 1.1V VBG */
+	ADCSRA |= (1 << ADEN) | (1 << ADPS2) | (1 << ADPS0); /* prescaler 1/32 */
+
+	_delay_us(500);
+
+	for (;;) {
+		ADCSRA |= (1 << ADSC);
+		while (ADCSRA & (1 << ADSC))
+			; 
+		v = (1100UL * 1023 / ADC);
+
+		for (int i = 0; i < 6; i++)
+			s[i] = 0;
+		itoa(v, s, 10);
+
+		uart_write("voltage: ");
+		uart_write_line(s);
+		_delay_ms(1500);
+	}
+
+	return 0;
+}