Measurement Computing CIO-DAC16-I - Manual (Page 13)

After calculating the code required for the D/A data, combine it with the code
required for the channel number.
For example, to set the output on channel 3 to 11.890625mA:
CODE = 11.890625mA - 4 / 16 * 4095 = 2020
The digital code for 2020 is 0111 1110 0100.
To this, you would add the value for channel 3 (0011) as the upper nibble for the
second register.
The end result is 0011 0111 1110 0100.
This is written to the registers as:
BASE + 0: 228 (or E4 hex)
BASE + 1: 55 (or 37 hex)
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