Servomex SERVOPRO Plasma, Operator'S Manual

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Plasma Gas Analyzer
23 02001001A_9
The communication parameters of the analyzer are:

Baud rate: 9600

Parity bits: none

Data bits: 8

Stop bits: 1
The serial port on the rear of the analyzer (Figure 2 item 6) is an RS232 ± 5.5 V 9-way
'D' type connector.
Pin(s) Use
1 Not used
2 Rx (to the analyzer)
3 Tx (from the analyzer)
4 Not used
5 0 V
6, 7, 8, 9 Not used
1
Figure 11 - RS232 CONNECTION PIN DETAILS
Standard RS-232 Interface - Transmission protocol
Note: see Appendix 4 for details of the transmission protocol for the Enhanced Interface
for use with External Valve Box
The different parameters are transmitted in the following order for the standard
interface:
ppm value sign, ppm value, TAB, flow, TAB, flow counts, TAB, cell counts TAB, status
and range, TAB, checksum, CR .
Each parameter is formatted as followed:

PPM value sign
: 1 byte equal to “+” or “-” in ASCII, depending on the
polarity of the ppm value;

PPM value : 6 bytes in ASCII (3 digits before the dot and two after);

Flow : 6 bytes in ASCII (3 digits before the dot and two after);

Flow counts : 8 bytes in ASCII;

Cell counts : 8 bytes in ASCII;

Status and range : bitwise (logical on 8 bits);
1 2 3 4 5
6 7 8 9