Matrix ETERNITY NE - Micros B

774 Matrix ETERNITY NE System Manual
Case 2: Negative Response from the CAS
The ETERNITY will make a maximum of 2 attempts to send the message. If the message is still not
transmitted successfully, it will drop the message and proceed for the transmission of the next message.
Case 3: No Response from the CAS
The ETERNITY will wait for 5 seconds and if no response is received from the CAS, it will drop the message
and proceed to the transmission of the next message.
Link Control Characters
5. Micros B
Handshaking protocol for Micros B is as shown below:
Case 1: Positive Response from the CAS
The first field of Text is always 'ac01' which marks the start of text. This field, however, is a part of the
message and not a link control character.
Case 2: Negative Response from the CAS
ETERNITY CAS
Text Plus Carriage Return > (Wait for 3 seconds)
< n
Text Plus Carriage Return > (Wait for 3 seconds)
ETERNITY CAS
Text plus Carriage Return > (Wait for 5 seconds)
No Response
Control Character Meaning Character ASCII value
ACK
Positive Acknowledgement by the CAS
(Indicates successful reception of data by the CAS)
HEX 79 (ASCII 'y')
NAK
Negative Acknowledgement by the CAS (Unsuccessful
reception of data by the CAS)
HEX 6E (ASCII 'n')
ETERNITY CAS
Text Plus Carriage Return >
< ACK
ETERNITY CAS
Text Plus Carriage Return > (Wait for 3 seconds)
< NAK
Text Plus Carriage Return > (Wait for 3 seconds)