Inficon VGC083A - 9 Communication Protocol (Serial Interface); 9.1 Device Specific Serial Communication Info; 9.2 INFICON RS232;RS485 Protocol Summary

72 tinb29e1-c (2019-10) VGC083A_B.om
9 Communication Protocol (Serial Interface)
The VGC083 provides RS232 and RS485 serial communications capability. The
following information and the command protocol summaries listed in the following
sub-sections of this chapter can be used to establish serial communications with
the device. Six distinct protocols (COMM type) are defined: INFICON RS232 and
RS485 protocol, RS232 and RS485 protocols compatible with GP series 307 and
358 controllers, and RS232 and RS485 protocols compatible with GP series 350
controllers. Note that GP 350 compatibility was implemented in January 2018. The
user has access from the front panel main menu to change settings for COM Type,
Baud Rate, Data Bits, Parity, Stop Bits and device Address (when using RS485).
Baud Rate is selectable at 300, 600, 1200, 2400, 4800, 9600, 19200 or
38400 baud.
Data bits may be set to either 7 or 8.
Parity selection may be set to None, Even or Odd.
Either 1 or 2 Stop Bits may be selected.
The device address when using RS485 can be within the range 00 to FF hexadeci-
mal (Default = 01).
There is a finite period of time between the time a command is sent from a terminal
(PC COM Port, for example) and the point in time in which the VGC083 starts to
send a response to that command. This delay is dependent upon the command
sent and the baud rate.
The maximum command repetition rate will depend on the length of the command
sent and the response received, as well as the baud rate. The maximum repetition
rate for the baud rate you are using can be found in the following table:
Selected Baud
Rate
Repetition Rate Receive to Transmit
Time
38400
38 ms
26 μs
19200
46 ms
52 μs
9600
61 ms
1.0 ms
4800
93 ms
2.0 ms
2400
156 ms
4.1 ms
1200
280 ms
8.3 ms
600
530 ms
16 ms
300
1030 ms
33 ms
The following notes are intended to be understood by the user when using
INFICON's RS232 and RS485 command protocol with the VGC083.
1. Default settings are 19,200 baud rate, 8 data bits, No Parity, 1 stop bit.
2. The baud rate can be set to different values using the front panel soft-keys.
3. All Responses are 13 characters long when COMM TYPE menu selected is
RS485 or RS232.
5. 'xx' is the address of the device (00 thru FF). For RS232, 'xx' is replaced with
two space characters.
9.1 Device Specific Serial
Communication Info
9.2 INFICON RS232 / RS485
Command Protocol
Summary