Kontron 104-AD128, User Manual

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Overview 5-3 104-ADIO128 (AD128) User’s Guide
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Overview
This chapter provides advanced programming details for customizing the functionality of the
104-ADIO128 (AD128).
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Using the Analog to Digital
Converter
This circuit is based on a Maxim ADC chip. Please refer to file MAX197.pdf in the \CHIPDOCS
directory on the CD-ROM. A conversion begins when a control byte is written to the ADC. The
control byte contains five bit fields: channel selection, bipolar/unipolar, range, acquisition
mode, and device mode.
Table 5-1. Control-Byte
The two bits in the device mode field select the clock source and the power state. Before putting
the ADC in a power down state, a conversion with Normal Operation selected should be triggered.
The chip will ‘remember’ this clock setting if the Standby power-down mode is subsequently
used. The Standby state is entered after a conversion is complete, there is no start-up delay on
Bit Description
Bit 0 Channel Selection Bit 0
Bit 1 Channel Selection Bit 1
Bit 2 Channel Selection Bit 2
Bit 3 Bipolar / Unipolar
Bit 4 Range
Bit 5 Acquisition Mode
Bit 6 Device Mode 0
Bit 7 Device Mode 1