Message completion and status bits – Rockwell Automation 1785-Vx0B, D17856.5.9 PLC-5 VME VMEbus Programmable Controllers User Manual User Manual
Page 53
Chapter 4
Ladder-Program Interfaces
4-6
The PLC-5/VME processor manipulates only two of the status bits in the
control word of the internal message control block:
DN
(done)
ER
(error)
For the copy operations, DN is not set until and unless the data are
successfully transferred. If an error occurs, ER is set and an error code is
placed in the message control block.
For the SVI operation, DN is set if and when the interrupt-acknowledge
cycle is successfully performed by the interrupt handler. If the message
syntax is incorrect (interrupt is not 1-7 or status/ID is not two hexadecimal
digits), ER is set along with an error code. For the CSF operation, DN is
set immediately.
For unrecognizable messages, ER is set along with an error code. The
error codes are:
Code
Explanation
0000H
Success
0001H
Invalid ASCII message format
0002H
Invalid file type
0003H
invalid file number
0004H
Invalid file element
0005H
Invalid VME address
0006H
Invalid VME transfer width
0007H
Invalid number of elements requested for transfer
0008H
Invalid VME interrupt level
0009H
Invalid VME interrupt status-id value
000AH
VMEbus transfer error (bus error)
000BH
Unable to assert requested interrupt (already pending)
000CH
Raw data transfer setup error
000DH
Raw data transfer crash (PLC switched out of run mode)
000EH
Unknown message type (message type not ASCII)
If the PLC-5/VME processor receives the same message control block with
the same msg_address field from the processor core with the .TO (timeout)
bit set, the current operation is terminated.
Message Completion and
Status Bits