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authorKeith Packard <keithp@keithp.com>2014-04-05 00:18:57 -0700
committerKeith Packard <keithp@keithp.com>2014-04-05 00:22:31 -0700
commit0d367fc24bfd0377db6f3b00a888a18245616767 (patch)
treef55c9890002dab3867aca0088e359ab389014528 /src/kernel/ao_convert_volt.c
parent8bd732ac9cb816630f46dd269448ff8422620df8 (diff)
altos: Report battery voltage instead of S at startup
This works on everything with a beeper except TeleMetrum v1.0 which just doesn't have enough flash space for the code. Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'src/kernel/ao_convert_volt.c')
-rw-r--r--src/kernel/ao_convert_volt.c10
1 files changed, 8 insertions, 2 deletions
diff --git a/src/kernel/ao_convert_volt.c b/src/kernel/ao_convert_volt.c
index 8556d423..7afc34bf 100644
--- a/src/kernel/ao_convert_volt.c
+++ b/src/kernel/ao_convert_volt.c
@@ -17,17 +17,23 @@
#include "ao.h"
-#define scale(v,p,m) ((int32_t) (v) * (AO_ADC_REFERENCE_DV * ((p) + (m))) / (AO_ADC_MAX * (m)))
+#define MUL(p,m) ((int32_t) AO_ADC_REFERENCE_DV * ((p) + (m)))
+#define ADD(p,m) (MUL(p,m)/2)
+#define DIV(p,m) ((int32_t) AO_ADC_MAX * (m))
+#define scale(v,p,m) (((int32_t) (v) * MUL(p,m) + ADD(p,m)) / DIV(p,m))
+#if HAS_APRS || HAS_BATTERY_REPORT
int16_t
ao_battery_decivolt(int16_t adc)
{
return scale(adc, AO_BATTERY_DIV_PLUS, AO_BATTERY_DIV_MINUS);
}
+#endif
+#if HAS_APRS
int16_t
ao_ignite_decivolt(int16_t adc)
{
return scale(adc, AO_IGNITE_DIV_PLUS, AO_IGNITE_DIV_MINUS);
}
-
+#endif