Matrix ETERNITY NE - Micros a

Matrix ETERNITY NE System Manual 773
Case 2: Negative Response from the CAS
The ETERNITY will make a maximum of 3 attempts to send the message. If the message is still not
transmitted successfully, it will drop the message and proceed to the transmission of the next message.
Case 3: No Response from the CAS
The ETERNITY will wait for 5 seconds to receive response from the CAS. If no response is received from the
CAS during this time period, it will drop the message and proceed to the transmission of the next message.
Link Control Characters
4. Micros A
Handshaking protocol for Micros A shall be as shown below:
Case 1: Positive Response from the CAS
The first field of Text is always 'ac01' which marks the start of text. However, this field is a part of message and
not a link control character.
SOM-(text)-EOM > (Wait for 3 seconds)
< NAK
SOM-(text)-EOM > (Wait for 3 seconds)
< NAK
SOM-(text)-EOM > (Wait for 3 seconds)
SOM-(text)-EOM > (Wait for 5 seconds)
No Response
Control Char. Meaning Character ASCII
Value
ACK Positive Acknowledgement by the CAS
(Indicates successful reception of data by the CAS)
HEX 06
NAK Negative Acknowledgement by the CAS
(Unsuccessful reception of data by the CAS)
HEX 15
SOM This marks the beginning of the message. Start of Message. HEX 0A (Line Feed)
EOM End of Message. This marks the end of message. HEX 0D or 0A or 0C
(CR or LF or FF)
ETERNITY CAS
Text Plus Carriage Return >
< y