User`s guide

52 DC 900-1343D
DDCMP Programmer’s Guide
2.6.2.2 Receiving Computer not Responding [131]
This exception is generated each seventh time that a reply (REP) message is sent because
no response was received from the remote computer. The REP is retried until a valid
response is received or the line is shut down.
2.6.2.3 Receive Message Lost due to Buffer Unavailability [133]
This exception is generated when the ICP must send a NAK in response to an incoming
data message because an ICP buffer was temporarily unavailable to receive the message.
Note that in this case no data is actually “lost” because the remote computer will receive
the NAK and retransmit the same data block again. The ICP accepts the data block
when an empty buffer becomes available.
2.6.2.4 Carrier Restored [134]
This exception is generated when the ICP detects a change of state in the Data Carrier
Detect (DCD) pin from off to on.
2.6.2.5 Disconnect (No DCD) [135]
This exception is generated when the ICP detects a change of state in the Data Carrier
Detect (DCD) pin from on to off.
2.6.2.6 DDCMP Start Received in RUN State [136]
This exception is generated when the ICP receives a DDCMP Start Link command and
the link is already in the RUN state. This exception causes the link to be set to the
HALTED state.
2.6.2.7 Received Message Too Large [138]
This exception signifies that a NAK was sent in response to an incoming data message
because the data size was larger than the configured ICP buffer size. This exception
causes the link to be set to the HALTED state.