APPENDIX B
RS-232
Connection
Protocol
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1.3.2 Feedback Command
The Ultimus V will send requested data back to the Host when feedback commands are used.
The feedback command sequence follows the steps listed below.
1.
The Host transmits an Enquiry (ENQ) command to the Ultimus V.
2.
The Ultimus V receives the ENQ and transmits an Acknowledge (ACK) back to
the host.
3.
When the Host receives the ACK, the Host will send the command packet.
STX+04+UA +C6+ETX for example.
4.
When the Ultimus V receives the command packet, the Ultimus V transmits an ‘A0’ command.
If there was an error in the command packet, or the command could not be executed, or the
transmission was interrupted and timed out, the Ultimus V will transmit an ‘A2’ command.
5.
If the host receives an ‘A0’ command, the host will send an ACK to indicate that it is ready
to receive data.
6.
When the ACK from the Host is received, the Ultimus V will send a command packet that
contains the data requested by the host. STX+05+D0+00001+96+ETX for example.
7.
Once the host receives the command packet, the host can either transmit another command
packet or the host can transmit an End of Transmission (EOT) command to end the sequence.
Host
Ultimus V
ENQ
ACK
‘UA’
‘A0’
ACK
‘D0001’
EOT
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