User`s manual
XP890056 s Software Reference
Using Digital-to-Analog Converter Boards
The follow steps summarize how to use the D/A converter boards.
1. Send a reset command to the PLCBus.
2. Place the address of the D/A converter on the PLCBus.
3. Send data serially to one of the D/A converters (RegisterA). When
Register A is filled, load the data to D/A converter Register B where it
is converted and output.
4. Use the boards analog output to control motors, attenuators or other
analog devices.
These steps are done using software drivers in Dynamic C function libraries.
Reset Boards on PLCBus
These Dynamic C functions are used to initialize the PLCBus. Use these
functions in a program before introducing any code to operate the relays.
VdInit()
Initializes the timer mechanism.
LIBRARY: VDRIVER.LIB
void plcBusReset()
Resets all expansion boards connected to the PLCBus.
When using this function, initialize timers with VdInit() before
resetting the PLCBus. All PLCBus devices must reset before perform-
ing any subsequent operations.
LIBRARY: EZIOPBDV.LIB
The XP8900 output voltages cannot be reset by resetting the
PLCBus. The rest of this chapter provides information on
setting or resetting the XP8900 output voltages.
void eioPlcRstWait()
Provides a delay long enough for the PLCBus to reset.
This function provides a delay of 12 seconds to ensure devices on the
PLCBus reset. Call this function after resetting the PLCBus.
LIBRARY: EZIOPBDV.LIB
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