User manual
Diagnosing Faults
Chapter 8
8-5
Figure 8.2
System
Status W
ord Error Indications
Remote BCM
module bits
Local BCM
module bits
8
9
10
11
12
13
14
15
0
1
2
3
4
5
6
7
If bit condition is:
1
Remote Local
BCM bit BCM bit
Error then the error description is:
HSSL
I/O
chassis
backplane
0 0 Normal operation.
0 1 Communication fault between local processor and BCM
1 0 Communication fault between remote processor and BCM
1 1 Communication fault in both systems.
Buffer full
0 0 Normal operation
0 1 For local, see Note 2
1 0 For remote, see Note 3
1 1 Both Notes 2 and 3 apply
0 0 Normal operation
0 1 Communication fault with local BCM module
1 0 Communication fault with remote BCM module
1 1 Communication fault between local and remote modules
1
Bit conditions: 1 = ON, 0 = OFF
2
Local BCM, if primary
,
is receiving 2nd segment after storing 1st, but did not send first segment to secondary BCM; if secondary
, received 2nd segment
without processing 1st.
3
Remote BCM, If primary, is receiving 2nd segment after storing 1st, but did not send first segment to secondary BCM; if secondary, received 2nd
segment without processing 1st.
4
This is dependent on the Fast Data Transfer mode either being enabled or not enabled.
5
This is an invalid condition for the primary 1785-BCM module.
Program-
ming Error
0 0 Normal operation
0 1 Programming error in local processor
1 0 Programming error in remote processor
1 1 Programming error in both PLC-5 processors
Remote I/O
Communi-
cation
0 0 Normal operation
0 1 Remote I/O communication failure between local processor and BCM
1 0 Remote I/O communication failure between remote processor and BCM
1 1 Remote I/O communication failure between both processors and BCMs
Processor
Fault
0 0 Normal operation
0 1 Invalid condition
1 0 Remote processor failure or is in PROGRAM mode
1 1 Invalid condition
Primary/
Secondary
System
0 0 Invalid during operation; valid for power-up and switchover only
0 1 Local processor is in primary mode; PRI LED on local BCM is lit
1 0 Remote processor is in primary mode; PRI LED on remote BCM is lit
1 1 Invalid condition
Data
Valid
0 0 Secondary BCM is not ready to send blocks of data to processor
(no complete segments available in buffer)
4
0
1
5
Local BCM is in secondary mode and has a block or complete
segment available to send processor
4
1
5
0
Remote BCM is in secondary mode and has a block or complete
segment available to send processor
4
1
1
Invalid condition