1
Publication 1747-UM013B-EN-P - January 2005
Chapter
5
RIO Block Transfer
This chapter contains the following information:
•
RIO block transfer theory of operation
•
RIO block transfer general functional overview
•
scanner’s block transfer buffer layout
•
detailed operation of RIO block transfer
•
RIO block transfer application considerations
•
steps for setting up a block transfer
•
quick reference for using status and control bits
•
block transfer control logic examples
RIO Block Transfer Theory
of Operation
This section provides a conceptual overview of block transfer as it
pertains to SLCs, RIO scanners, and remote devices. For specific
functionality details, refer to Using Block Transfer Instructions (BTR
and BTW) on page 5-5.
What Is RIO Block Transfer?
RIO Block Transfer is a data transfer mechanism that allows you to
control the transfer of up to 64 words of data to or from a remote
device over the Allen-Bradley RIO link. A
Block Transfer Read
(BTR)
is used when a remote device transfers data to the SLC. A
Block
Transfer Write
(BTW) is used when an SLC processor writes data to a
remote device.
The diagrams on the following pages illustrate the concepts of how
block transfers occur using an SLC processor, an RIO scanner, and a
remote device. The first diagram illustrates the path a block transfer
follows. The second and third diagrams illustrate in greater detail the
theory of operation of a BTR and a BTW, respectively.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
