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5. RS-232 Communication Protocol
The Sound Level Meter
3&(
has an RS-232 serial interface. User can modify the
configuration of the sound level meter via a serial interface and control the sound level meter
to run and to stop, and get the current measurement parameters and results for further
processing. Operation via serial interface does not affect keyboard operation.
5.1 Hardware Configuration and Settings of Interface
3&(
uses three-wire serial interface, the physical socket is PS/2-6 pins. Below is
the definition of RS-232 interface:
RS-232 transfer settings:
Transfer Mode
Full-duplex
Synchronous / Asynchronous Mode
Asynchronous transfer
Baudrate
4800 bps, 9600 bps, 19200 bps
Data Bits
8 bit
Stop Bits
1 bit
Parity
None
Flow Control
Follow the time data in the rated parameters table
☆
Note:
RS-232 connector housing should be grounded and recommended to use ground
shield wire. Please be sure to use quality and reliable RS-232 to RS-485 adaptor.
5.2 Transfer Protocol
3&(
RS-232 interface protocol is based on a block transfer, as shown below:
Send command block
Send response block
1.
NC
2.
GND
3.
NC
4.
TXD
5.
NC
6.
RXD
3
2
1
4
5
6
PCE-428 / 430 / 432