Chapter 4 Register Structure and Format 33
4.3 Channel Number and A/D Data ๎‚—BASE+0 and BASE+1
These two bytes, BASE+0 and BASE+1, hold the result of A/D
conversion data. The 12 bits of data from the A/D conversion are
stored in BASE+1 bit 3 to bit 0 and BASE+0 bit 7 to bit 0. BASE+1
bit 7 to bit 4 hold the source A/D channel number.
Table 4-2: Register for channel number and A/D data
AD11 ~ AD0 Result of A/D Conversion
AD0 is the least significant bit (LSB) of the A/D data, and AD11 is the
most significant bit (MSB).
CH3 ~ CH0 A/D Channel Number
CH3 ~ CH0 hold the number of the A/D channel from which the data
is received. CH3 is the MSB and CH0 is the LSB.
4.4 Software A/D Trigger ๎‚— BASE+0
You can trigger an A/D conversion by software, the cardโ€™s on-board
pacer or an external pulse. Bit 2 to bit 0 of register BASE+6 can
select the trigger source (see page 39 and page 40 for the register
layout of BASE+6 and programming information). If you select
software triggering, a write to the register BASE+0 with any value will
trigger an A/D conversion.
Read Channel Number and A/D Data
Bit # 7 6 5 4 3 2 1 0
BASE+1 CH3 CH2 CH1 CH0 AD11 AD10 AD9 AD8
BASE+0 AD7 AD6 AD5 AD4 AD3 AD2 AD1 AD0