
Instruction Manual
MX4A Active Convection Gauge
3.2
Communications Specifications
Table 2: RS-485 Communication Specifications
Interface
RS-485 compatible
Data Transfer Method
Synchronous/half duplicate method
Baud Rate
1200/4800/9600/19200/38400
Default Data Format
1 start bit, 8 data bits, 0 parity bits, 1 stop bit
Error Detection
Parity bit
Parity Bit
None/even/odd
Stop Bit
1
Transfer Distance
Max 100 meters
3.3
RS-485 Command List
Table 3: RS-485 Commands
Command
Description
R1
Read units
R2
Read SP1L and SP1H
R3
Read SP2L and SP2H
W1
Set pressure units
W2
Set SP1L,SP1H
W3
Set SP2L,SP2H
W4
Set gas type
S1
Read pressure data
RC1
Read vacuum adjustment
RC2
Read 1 Torr adjustment
RC3
Read 70 Torr adjustment
RC4
Read atmosphere adjustment
WC1
Write vacuum adjustment
WC2
Write 1 Torr adjustment
WC3
Write 70 Torr adjustment
WC4
Write atmosphere adjustment
email: [email protected]
tel: +1 215 947 2500
web: frederickscompany.com
mx4a_im rev L
14 of 16