Addressable Rs232 Connections - Promax GR-205 Manuel D'instructions

USER'S MANUAL. GR-205

5.3.3 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
Data Bits: 8
09/2004
Parity: None
Stop Bits: 1
Page 19