Emerson PACSystems RSTi-EP - Page 278

User Manual Section 5
GFK-2958L May 2021
Detailed Description of I/O Modules 264
Process Input Data EP-5261
Byte
Format
Name
Bit
Description
Remarks
IB0
Word
Status and
Diagnosis
IX0.0
Data in the
receive memory
RX = 0: Receive memory is empty
RX = 1: A telegram (or telegram segment)
in the receive memory is ready for
transmission.
IX0.1
Receive memory
nearly full
Only 10 characters are left in the receive
memory. XOFF will be set if parameterized.
IX0.2
Not used
IX0.3
RX_CNT
The RX_CNT value is assigned to each data
segment of the process input data while
transmission. The sequence or the RX_CNT
values is:
Binary: 00, 01, 10, 11, 00, ...
Decimal: 0, 1, 2, 3, 0, ...
A faulty data sequence indicates missing
data segments.
IX0.4
RX_CNT
IX0.5
TX_CNT_ACK
The TX_CNT_ACK value is a copy of the
TX_CNT value, which has been transferred
together with the last data segment of the
process output data. TX_CNT_ACK
acknowledges that the data has been taken
over successfully.
IX0.6
TX_CNT_ACK
IX0.7
STAT
STAT = 1: Communication with the device
is without fault.
STAT = 0: Faulty communication with the
device.
IB1
Word
Length of the
data segment /
or of the
subsequent
diagnosis data
RX
Length of the data / diagnosis data in this
frame
IB 2 ... IB 7 or
IB 2 ... IB 15
Received data
User data of the
transferred
telegram
segment