From 57e9d1a5c00dc7dc5cf3149c35a8004b5f7aab7f Mon Sep 17 00:00:00 2001
From: Sadeep Madurange <sadeep@asciimx.com>
Date: Thu, 1 May 2025 11:05:40 +0800
Subject: Measure vcc.

---
 batchk/main.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 batchk/main.c

(limited to 'batchk/main.c')

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;
+}
-- 
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