From baaa035cf93340b8f2c626bdba47e8066cf40067 Mon Sep 17 00:00:00 2001
From: Selene ToyKeeper
Date: Wed, 22 Nov 2023 05:34:26 -0700
Subject: ADC voltage: battcheck 3 digits, fixed t1616, switched back to 8-bit
 internal volt unit

Before this branch, `voltage` was 6 bits: Volts * 10
A couple patches ago, I upgraded it to 16 bits: 65535 * Volts / 10.24
That costs too much extra ROM on attiny85 though, for extra precision
it doesn't even use... so I switched back to an 8-bit value.  It's still
more precise than before though: Volts * 40
... and battcheck displays an extra digit now, on devices with ROM for it.
... and battcheck waits a second to get a more accurate measurement
    before displaying the first value.  It has *much* less variation
    between first and later readings now.

Also:
- got t1616 builds working again (tested fc13 and thefreeman-boost-fwaa)
- upgraded t1616 voltage and temp to 12-bit (10 bits + 4x oversampling)
- removed expensive temp conversion from t1616 ADC interrupt
- recalibrated t1616 bogomips again; runs faster after interrupt fix
- increased t1616 internal VDD measurement resolution by 36% (1.5V Vref, not 1.1V)
- fixed sloppy setting of Vref bits

I still need to test / update other t1616 builds,
and fix all the t85 + t1634 code and build targets.
---
 fsm/adc.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'fsm/adc.h')

diff --git a/fsm/adc.h b/fsm/adc.h
index 65d7d6c..0c0a9e5 100644
--- a/fsm/adc.h
+++ b/fsm/adc.h
@@ -17,11 +17,11 @@ volatile uint8_t adc_reset = 2;
 #endif
 // low-battery threshold in volts * 10
 #ifndef VOLTAGE_LOW
-#define VOLTAGE_LOW 29
+#define VOLTAGE_LOW (4*29)
 #endif
 // battery is low but not critical
 #ifndef VOLTAGE_RED
-#define VOLTAGE_RED 33
+#define VOLTAGE_RED (4*33)
 #endif
 // MCU sees voltage 0.X volts lower than actual, add X/2 to readings
 #ifndef VOLTAGE_FUDGE_FACTOR
-- 
cgit v1.2.3