Rockwell Automation 57C570 AutoMax PC3000 User Manual - Manual (Page 179)

16Ć3
16.3 Initiating Scanning
Your initialization program should only initiate scanning after the
data rate has been set.
To start the PC3000 scanning the enabled racks, set bit 1 of register
768 to on (1). This bit is labeled Start Scanning in the scanner's
Variable Configurator form.
Once you initiate scanning and the scanner is in RUN mode, the
PC3000 sets the data rate as defined by the value in register 769
and starts updating I/O from the remote racks. Once scanning has
begun, the module clears the Start Scanning bit (register 768, bit 1).
If all the enabled racks are communicating, the PC3000's remote I/O
LED (green) should be on. If the serial card is present, the
7Ćsegment LEDs should be off.
16.4 Placing the Scanner in RUN Mode
When the scanner has been initiated and it is in RUN mode, the
following occurs:
D inputs are updated
D outputs are enabled
D I/O can be forced
Inputs are updated as long as the Start Scanning bit is enabled.
However, your initialization program must place the scanner module
in RUN mode so that outputs in the remote racks being scanned are
updated.
To place the scanner in RUN mode, set bit 0 of the variable
associated with register 768 to on (1). This bit is labeled Scan Mode
in the scanner's Variable Configurator form.
The Scan Mode bit is reset to off (0) whenever a STOP ALL error
occurs. For a list of STOP ALL error codes, see chapter 19.
16.5 What to Do Next
Begin creating and implementing your control programs.