Rockwell Automation 1785-Vx0B, D17856.5.9 PLC-5 VME VMEbus Programmable Controllers User Manual - Manual (Page 91)

Chapter 6
PLC-5/VME Processor
Communications Commands
6-22
Message Format
DST
00
PSN
00
SRC
00
PSN
00
CMD
0F
STS
00
TNS FNC
53H
Command Packet
DST
00
PSN
00
SRC
00
PSN
00
CMD
4FH
STS EXT
STS
Reply Packet
Memory Segment TNS
Pointers
LNG
Start Pointer
Segment 1
End Pointer
Upload/download Segments
Compare Segments
Start Pointer
Segment 2
End Pointer
Repeats for the number of
transfer segments in the LNG field
Memory Segment Pointers
LNG
Start Pointer
Segment 1
End Pointer Start Pointer
Segment 2
End Pointer
LNH
Hi
LNH
Lo
Segment Identifier
LNG — the number of transfer or compare segments that follow this single byte quantity.
Segment X — repeats for the number of transfer segments in the LNG field.
Segment Identifier
Segment X
Segment X
8 bytes 1 byte
8 bytes 1 byte
Error Codes
The STS byte contains 00H if no error. When detected, the PLC-5/VME
processor reports errors in its reply packet as follows:
STS EXT STS Description
00H – No error
F0H 0BH Access denied—PLC-5/VME processor in upload or download mode
Refer to page D-3 for additional information on PCCC status codes.
Sample API Module
For a sample
interface
header file: Refer to page: For a sample
implementation
source file: Refer to page:
P40VULA.H B-86 P40VULA.C B-87