User`s manual

XP860030 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 (RegisterA). When

is converted and output.

4. Use the boards 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

 void eioPlcRstWait()

Provides a delay long enough for the PLCBus to reset.

This function provides a delay of 12 seconds to ensure devices on the

PLCBus reset. Call this function after resetting the PLCBus.

LIBRARY: EZIOPBDV.LIB

 long int eioErrorCode

Represents a global bit-mapped variable whose flags reflect error

occurrences.

This register for this variable is initially set to 0. If the application tries

to access an invalid channel, the flag EIO_NODEV (the first bit flag) is

set in this register. Note that the other bits in EIO_NODEV deal with

networked controllers.