Yaskawa Modicon 800 Series Remote I/O Network for use on Microtrac LAN - Manual (Page 23)

4 OPERATION
22 PLC Gateway Status
5/24/96
display meaning
EIVA When the PLC gateway receives an allocation message, it
decodes the channel number into drop and slot numbers. If
either of these numbers is invalid, then this message is
displayed. An allocation error message is returned to the
sending node.
ELIA When the PLC gateway receives a logical input allocation
message, this error message could appear because the internal
allocation table is full and cannot handle another allocation.
The allocation table has room for 1024 allocations. A logical
allocation uses one element in the table.
ELOA When the PLC gateway receives a logical output allocation
message from the MicroTrac LAN, this error message could
appear for any of the following reasons:
• The internal allocation table is full and cannot handle
another allocation. The allocation table has room for
1024 allocation. A logical allocation uses 1 element in
the table.
• The bits specified in the allocation message overlap with
bits already allocated by another node.
• The bits specified by the allocation message are not
exactly the same as the bits already allocated by this node.
EMMA This indicates a mismatch during allocation.
When the PLC receives an allocation message from the
network, it decodes the channel number into a drop and slot
number and then requests the configuration for that drop from
the Modicon PLC. Once the configuration has been received,
the gateway checks to make sure that the module in that slot is
the correct one. If not, then this message is sent to the node
that issued the allocation message.
Troubleshoot: Check the Traffic Cop in the Modicon PLC.
For the drop and slot specified in the allocation
message, the following modules are expected in the
allocation message:
0X10; LOGO - B805, 16 point discrete input module
0X11; NUMO - B865, 8 channel register input module
0X12; LOGI - B804, 16 bit discrete output module
0X13; NUMI - B864, 8 channel register output module
PLC Gateway
Status
(continued)
RD 3004-20