Use actterm with step, Single char ack f0, 1 or 3, Single char ack c1 or c2 – ProSoft Technology MVI69-101S User Manual
Page 30: Maximum asdu resp len, Cause of trans octets, Freeze start type
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MVI69-101S ♦ CompactLogix or MicroLogix Platform
Configuring the MVI69-101S Module
IEC 60870-5-101 Slave Communication Module
Page 30 of 149
ProSoft Technology, Inc.
March 16, 2009
2.3.11 Use ACTTERM with Step
Use ACCTERM with step : 1 #1=Yes, 0=No ACTCON is last response
#to cmd
This parameter determines if an ACCTERM will be sent. If the parameter is set to
Y, then step commands will issue an ACCTERM when the command is
complete. If the parameter is set to N, ACTCON is the last response to a step
command.
2.3.12 Single Char ACK F0, 1 or 3
Yes or No
If set to Y, a single character ACK (0xE5) will be sent instead of a fixed length
ACK (secondary function code 0) in response to a primary link function code 0, 1
or 3 if there is no access demand for class 1 data (ACD=1). If set to N, the fixed
length ACK will be sent.
2.3.13 Single Char ACK C1 or C2
Single char ACK C1 or C2 : 1 #1=Single E5 resp when no C1 or C2 data
If set to Y, a single character ACK (0xE5) will be sent instead of a fixed length
NACK (secondary function code 9) when no response user data is available. If
set to N, the fixed length NACK will be sent.
2.3.14 Maximum ASDU Resp Len
Maximum ASDU Resp Len : 249 #Max ASDU response message length may
#have value from 25 to 252 (usually 252).
This parameter limits the maximum size of the ASDU portion of a response
message. Most applications will use a value of 252.
2.3.15 Cause of Trans Octets
Cause of Trans Octets : 2 #Number of COT octets (1 or 2)
This parameter sets the COT length to 1 or 2. The second octet stores the
originator address passed in the register. Spontaneous and cyclic data will
always respond with the originator address set to 0.
2.3.16 Freeze Start Type
D=Day, H=Hour, M=Minute, N=Not used
The Freeze Start Type parameter defines when the module starts sending the
M_IT messages.