6 - programming the 1771-dcm, Programming the 1771-dcm, Local processor logic – Rockwell Automation 1771-DCM USER MANUAL 1771-DCM User Manual

Page 22

Advertising
background image

Chapter

6

6Ć1

Programming the 1771-DCM

We assume that you are familiar with block transfer programming, that
you can allocate data table areas for read and write data blocks, and that
you can manipulate data to and from these data blocks. We will confine
this discussion to programming characteristics unique to the 1771–DCM.

The local processor, typically a PLC–2 family mini–processor or PLC–5
family processor, reads and writes data to the 1771–DCM using block
transfers. Programming examples (Figure 6.1, Figure 6.2) assume that the
1771–DCM is set for six–word block transfers.

Figure 6.1

Local Processor Programming Example (PLC-2)

EN

FILE TO FILE MOVE

Counter Address:

Position:

File Length:

File A:

0040

001

006

0300-0305

File R: 0400-0405

Rate per Scan: 006

0040

17

DN

0040

15

17

113

10

300

Buffer File

Data Valid Bit

BTR Done Bit

EN

BLOCK XFER WRITE

Data Address:

Module Address:

Block Length:

File:

0031

131

06

0200-0205

013

16

DN

113

16

EN

013

17

DN

113

17

BLOCK XFER READ

Data Address:

Module Address:

Block Length:

File:

0030

131

06

0300-0305

Programming the 1771-DCM

Local Processor Logic

Advertising