User guide
4–7Using Full-duplex Protocol to Send and Receive Messages
Publication
17706.5.16 - October 1996
How the Receiver Operates
The receiver must be capable of responding to adverse situations.
Some of the problems that can occur are:
• the message sink is full, so the receiver has nowhere to put
a message
• a message can contain a parity error
• the BCC or CRC can be invalid
• the DLE STX or DLE ETX BCC/CRC may be missing
• the message is too long or too short
• a false control or data symbol occurs outside a message
• a false control symbol occurs inside a message
• the DLE ACK response is lost, causing the transmitter to send a
duplicate copy of a message already passed to the message sink