Baud Rate is set as described above in Address and Baud Rate Selection; the other parameters
are fixed as follows:
Start Bits: 1
Parity: None
Data Bits: 8
Stop Bits: 1
Addressable RS232 Connections
For addressable RS232 operation pins 7, 8 and 9 of the instrument connector are also used.
Using a simple cable assembly, a 'daisy chain' connection system between any number of
instruments, up to the maximum of 32 can be made, as shown below:
The daisy chain consists of the transmit data (TXD), receive date (RXD) and signal ground lines
only. There are no control/handshake lines. This makes XON/XOFF protocol essential and allows
the inter-connection between instruments to contain just 3 wires. The wiring of the adaptor cable
is shown below:
All instruments on the interface must be set to the same baud rate and all must be powered on,
otherwise instruments further down the daisy chain will not receive any data or commands.
The other parameters are fixed as follows:
Start Bits: 1
Parity: None
Data Bits: 8
Stop Bits: 1
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