Rockwell Automation 57C570 AutoMax PC3000 User Manual - Manual (Page 159)

14Ć1
14.0 CONFIGURING AND
PROGRAMMING BLOCK
DATA TRANSFERS TO AĆB
I/O MODULES
For information about: See this section:
About BlockĆTransfers 14.1
Configuring BlockĆTransfers 14.2
Programming BlockĆTransfers 14.3
Monitoring BlockĆTransfer Status 14.4
What to Do Next 14.5
14.1 About BlockĆTransfers
Many I/O modules and remote I/O adapters, such as analog
modules and operator interfaces, communicate to scanners solely
by blockĆtransfer. A blockĆtransfer operation allows the transfer of a
block of data to or from an I/O module during one remote I/O scan.
A maximum of 64 words can be transferred during one request, and
you can program a maximum of 48 blockĆtransfer requests. One
request can be processed per rack per remote I/O scan, but
multiple requests to a rack can be initiated.
When programming a blockĆtransfer, you specify whether it is a
continuous or nonĆcontinuous read or write request.
14.1.1 About BlockĆTransfer Read and Write Requests
The AutoMax PC3000 can perform biĆdirectional blockĆtransfers,
meaning it can issue blockĆtransfer read and blockĆtransfer write
requests. You must specify blockĆtransfer read operations when you
want to gather input and status data from the module and
blockĆtransfer write operations when you want to send output or
configuration data to the module.