ProSoft Technology MVI71-GSC - Manual (Page 26)

MVI71-GSC ♦ PLC Platform Installing and Configuring the Module
Generic Serial Communication Module
Page 26 of 82 ProSoft Technology, Inc.
January 31, 2008
Error Bit in
Word Description
Cfg_Wtimeout Bit 10 The write message timeout parameter is set to zero. The
module assumes a value of 5000 milliseconds.
Bit 11
Bit 12
Bit 13
Bit 14
Err_ROverflow Bit 15 Data is being received faster on the port than the ladder logic
can process the read blocks. Alter the configuration of the
module or the connected device. Receive data is being lost.
The Err_ROverflow bit is an important bit to monitor in the ladder logic. This bit is
set anytime data is lost on the receive port. The module will buffer all received
data until the termination condition programmed for the module exists or the
receive buffer reaches a size of 4096 bytes. When the termination condition is
met, the received data will be transferred from the module to the processor. Data
will be transferred in blocks of 50 bytes per transfer for the BTR/BTW interface
and 400 bytes per transfer for the side-connect interface. If data is received on
the port and the termination condition is present and the last received data set
has not been completely, the Err_ROverflow bit will be set for the port and the
newly received data will be flushed from the receive buffer. Therefore, it will be
lost. This error flag is important to monitor because it will indicate when data is
lost on the receive port. The ladder logic must handle the data as fast as the
module receives it.
2.1.4 MVI71-GSC Status Data Definition
This section contains a description of the members present in the status data
area. This data is transferred from the module to the processor as a read block.
The following table display the structure of the block used to transfer the data
when the BTR/BTW interface is utilized:
Word
Offset Description
0 Block Sequence Number (Bumped each scan by module) (0 to 127)
1 Number of bytes received on Port 1 is set to zero.
2 Number of characters transmitted (0 to 50) from last block write Port 1
3 Program cycle counter
4 to 5 Product name as ASCII string
6 to 7 Revision level as ASCII string
8 to 9 Operating system level as ASCII string
10 to 11 Run number as ASCII string
12 Number of blocks transferred from module to processor
13 Number of blocks transferred from processor to module
14 Number of blocks parsed by module
Module
Status
15 Number of block errors in module