Adc Control And Status Register - Motorola MC68HC05T16 Technical Data Manual

10.3

ADC Control and Status Register

Address bit 7
$3C RESULT
This read/write register, located at address $3C, contains six control bits and one status bit.
RESULT - Comparator Status (Read Only)
1 (set) – AD4-0 value greater than analog in.
0 (clear) – AD4-0 value is less than analog in.
CHNL - Channel Select
1 (set) – ADCIN1 is selected for conversion.
0 (clear) – ADCIN0 is selected for conversion
AD4-0 - ADC Digital Result
These bits are written by the user to perform successive approximations in software. When a value
causes the RESULT bit to change state from the value immediately before or after it, AD4-0 are
considered to be the digital equivalent of the analog input. Note that when AD4-0 are all 1's, ADC
is virtually turned off to minimize power consumption.
MC68HC05T16
bit 6 bit 5 bit 4
CHNL AD4
ANALOG TO DIGITAL CONVERTER
bit 3 bit 2 bit 1
AD3 AD2 AD1
State
bit 0
on reset
AD0 u000 0000
TPG
MOTOROLA
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