From 227b54b1095e47ae9d0ab4b4c2a49862fd708559 Mon Sep 17 00:00:00 2001
From: Selene ToyKeeper
Date: Mon, 16 Mar 2020 04:13:55 -0600
Subject: fixed calc_voltage_divider() (use 10-bit calibration values, not
 8-bit)

---
 spaghetti-monster/fsm-adc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spaghetti-monster/fsm-adc.c b/spaghetti-monster/fsm-adc.c
index 7880238..e7b7feb 100644
--- a/spaghetti-monster/fsm-adc.c
+++ b/spaghetti-monster/fsm-adc.c
@@ -112,7 +112,7 @@ inline void ADC_off() {
 #ifdef USE_VOLTAGE_DIVIDER
 static inline uint8_t calc_voltage_divider(uint16_t value) {
     // use 9.7 fixed-point to get sufficient precision
-    uint16_t adc_per_volt = ((ADC_44<<7) - (ADC_22<<7)) / (44-22);
+    uint16_t adc_per_volt = ((ADC_44<<5) - (ADC_22<<5)) / (44-22);
     // shift incoming value into a matching position
     uint8_t result = ((value>>1) / adc_per_volt) + VOLTAGE_FUDGE_FACTOR;
     return result;
-- 
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