ProSoft Technology MVI56-GEC - Manual (Page 40)

Ladder Logic MVI56-GEC ♦ ControlLogix Platform
User Manual Generic ASCII Ethernet Communication Module
Page 40 of 108 ProSoft Technology, Inc.
October 8, 2010
3.1.1 GECBackplane (Backplane Object)
The GECBackplane object stores all the variables required for the data transfer
operation between the module and the controller. The LastRead data member is
used as the handshaking byte to indicate the arrival of new data from the
module. The following table describes the structure of the object.
Name Data Type Description
LastRead INT Sequence number of last block read
LastWriteCount INT Last number of bytes written
CurBlock INT Sequence number for current block
UnitNumber INT Current server or client in read block
RxLen INT Length of message received
TxServer INT Server number for current transmit
TxCount INT Number of bytes processed from last tx
message
The other members of the object can be utilized in the ladder logic to assist in the
data transfer operation.
3.1.2 GECBlkStat (Block Error Status Object)
The GECBlkStat object holds the status data related to the data transfer between
the module and the controller. Each read and write block transferred between the
module and the controller is counted in the Read and Write data members,
respectively. Each write block that is parsed by the module is counted in the
Parse data member. The Err member is incremented each time a bad block is
transferred between the two devices, or there is an error in the backplane driver
in the module. The following table describes the structure of this object.
Name Data Type Description
Read INT Number of blocks read by the module
Write INT Number of blocks written by the module
Parse INT Number of blocks parsed by the module
Err INT Number of block transfer errors