ProSoft Technology 5201-DFNT-DNPS - Manual (Page 65)

Reference ProLinx DNPS ♦ ProLinx Gateway
User Manual DNP 3.0 Slave
ProSoft Technology, Inc.
Page 65 of 86
December 1, 2009
The timing parameters defined above must be set correctly for successful use of
the collision avoidance feature. A timing diagram displaying the data and modem
control lines used with the collision avoidance scheme is shown below. This
example displays the state of the signal lines in transmitting a message from Unit
1 to Unit 2.
UNIT 1:
RTS
DCD
TX Data
RX Data
UNIT 2:
RTS
DCD
TX Data
RX Data
Wait for DCD to remain
low for minimum time +
random time before
sending data.
RTS on
delay RTS off
delay
DCD signal must be enabled
for at least the RX-enable time
before the data is received.
3.5 IIN Response: Slave Port
The module defines the IIN data bits returned with a response message from the
module to a DNP master unit. These bits should be interpreted and handled by
the master. These bits report status and error information to the master DNP
device.
The following is a description of the word:
3.5.1 First Byte
Bit Description
0 All stations message received. Set when a request is received with the destination
address set to 0xffff. Cleared after next response. Used to let master station know
broadcast received.
1 Class 1 data available. Set when class 1 data is ready to be sent from the slave to the
master. Master should request class 1 data when this bit is set.
2 Class 2 data available. Set when class 2 data is ready to be sent from the slave to the
master. Master should request class 2 data when this bit is set.
3 Class 3 data available. Set when class 3 data is ready to be sent from the slave to the
master. Master should request class 3 data when this bit is set.