Parker Hannifin VIX250IM, VIX500IM 4. Control of ViX Drives

4. Control of ViX Drives

This section introduces you to the operation of the ViX stepper drive, the implementation of

motion control moves and the way commands are used. Basic controller operation is

described together with the code structure. How system information is signalled via system

variables and the use of various flag registers for status and fault reporting are described.

Both basic and advanced motion control functions are covered including elements of event

driven code used for fault reporting and registration.

ViX intelligent drives have an integrated controller which can be driven directly by a PC over

a serial link, or programmed to respond to code selected by event triggers or user

instructions.

Direct operation of the controller over a serial link can be used for program

development/downloading purposes or direct on-line control from an industrial PC or PLC.

When used directly the controller will accept commands prefixed with the drive’s address

and will action the commands as they are received. In direct mode any controlling

application program is stored in a remote location and is only downloaded to the drive when

required.

This mode allows a program stored within the drive to control operations. The program can

be written off-line on a PC and then downloaded to the drive via a serial link. The application

program is stored within the drive and is automatically invoked at power up provided it is

enabled by the <a>ARM1X command and the program has a START label. Alternatively,

you could directly issue a <a>GOTO(START) command.

You write program code as a series of blocks. Each code block has a unique label at the

beginning and is terminated with an END label (block delimiter). The use of labels allows the

code structure of the form illustrated in Figure 4-1, which shows the block nature together

with an example of code.

Declare

Declare every label used in a program, apart from START, REG, NOREG and FAULT that

have been pre-declared. If a label is declared, but not defined, a runtime error will be

signalled when it is called.

Note: START, REG, NOREG and FAULT are all reserved labels.

You can only declare labels in the command line at the start of a program or within the

START code. The choice is between memory efficiency and the retention of declared labels