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.

1 files changed, 16 insertions, 4 deletions

diff --git a/arch/attiny1616.h b/arch/attiny1616.h
index b4e17fc..57b0023 100644
--- a/arch/attiny1616.h
+++ b/arch/attiny1616.h
@@ -9,9 +9,11 @@
 ////////// clock speed / delay stuff //////////
 
 #define F_CPU  10000000UL
-#define BOGOMIPS  (F_CPU/4700)
+#define BOGOMIPS  (F_CPU/4350)
 #define DELAY_ZERO_TIME  1020
 
+inline void mcu_clock_speed();
+
 ///// clock dividers
 // this should work, but needs further validation
 inline void clock_prescale_set(uint8_t n);
@@ -44,20 +46,30 @@ inline void mcu_adc_sleep_mode();
 
 inline void mcu_adc_start_measurement();
 
-inline void mcu_adc_on();
+//inline void mcu_adc_on();
 
 inline void mcu_adc_off();
 
 #define ADC_vect  ADC0_RESRDY_vect
 inline void mcu_adc_vect_clear();
 
+//// both readings are left-aligned
+//inline uint16_t mcu_adc_result();
+
 // read ADC differently for temperature and voltage
 #define MCU_ADC_RESULT_PER_TYPE
-
 inline uint16_t mcu_adc_result_temp();
-
 inline uint16_t mcu_adc_result_volts();
 
+// return Volts * 40, range 0 to 6.375V
+#define voltage_raw2cooked  mcu_vdd_raw2cooked
+inline uint8_t mcu_vdd_raw2cooked(uint16_t measurement);
+inline uint8_t mcu_vdivider_raw2cooked(uint16_t measurement);
+
+// return (temp in Kelvin << 6)
+#define temp_raw2cooked  mcu_temp_raw2cooked
+inline uint16_t mcu_temp_raw2cooked(uint16_t measurement);
+
 inline uint8_t mcu_adc_lsb();