Varian Turbo-V 301, Инструкция по эксплуатации

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TECHNICAL INFORMATION
7 5 87-900-940-01 ( F )
RS 232 Communication Descriptions
Communication format:
•
8 data bit
•
no parity
•
1 stop bit
•
The baud rate is programmable via front panel from
600 to 9600 baud. The controller is factory-set for
9600 baud operation.
NOTE
When a baud rate of 2400, 4800, 9600 baud is used,
the requested information from Host to controller must
be sent with a minimum interval of 1 second to avoid
the controller hang-up.
Communication protocol:
Host = Master
Turbo-V 301 Controller = Slave
The communication is performed in the following way:
Host Turbo-V 301 Controller
Request is an ASCII character identifying the action that
must be performed by the controller or the requested
information.
Allowed ASCII characters:
•
"A" = START
•
"B" = STOP
•
"C" = Low Speed ON
•
"D" = Low Speed OFF
•
"E" = Request for operational parameters
•
"F" = Pump times zeroing
•
"G" = Parameters reading
•
"H" = Parameters writing
•
"I" = Request for operating status
•
"J" = Request for numerical reading
•
"K" = Request for counters reading.
CRC corresponds to the sum (with inverted sign) of all the
preceding bytes.
e.g., the START command "A" in ASCII code = 41;
inverted it will be: FF + 1 - 41 = BF.
CHARACTER ASCII CONVERTED ASCII
FOR CRC CALCULATION
"A"
CRC
41h
-
-
BFh
"B"
CRC
42h
-
-
BEh
"C"
CRC
43h
-
-
BDh
"D"
CRC
44h
-
-
BCh
"E"
CRC
45h
-
-
BBh
"F"
CRC
46h
-
-
BAh
"G"
CRC
47h
-
-
B9h
"H" 48h -
"I "
CRC
49h
-
-
B7h
"J"
CRC
4Ah
-
-
B6h
"K"
CRC
4Bh
-
-
B5h
"ACK"
CRC
06h
-
-
FAh
"NACK"
CRC
15h
-
-
EBh
Answer = after a request from the host, the
Turbo-V 301 controller will answer in one of the following
ways:
•
ACK
•
NACK
•
Message
When the Request is "A, "B”, "C", "D", "F", the Turbo-V
301 controller will Answer the ACK or NACK.