Saia-Burgess
Controls Ltd.
Manual PCD7.D23x│Document 26/795; Edition E7│15.04.2005
Special confi guration with several PCD7.D23x terminals
Quickstart
1-11
1
1.4
Special configuration with several terminals with RS 422 Free Terminal
Protocol (Multi Drop) (mixing is not possible)
Available for PCS1 without display and all the range of PCD.
This mode allows the connection of several terminals on one RS 422 port. In this
case, only one terminal is active (sender and receiver) and the other are passive
(Read only).
PCD7.D23x setup:
Baudrate:
up to 19200 bps
Serial mode:
RS 422 Free Terminal Protocol (Multi Drop)
Addresses:
Same address for all terminals
Only the terminal with the full connections TXD /TXD and RXD /RXD is full active
(single knob and display). The other terminals with the connections RXD /RXD work
only as displays.
Advantages:
●
just one terminal is full master.
●
Other terminals have a short refresh time.
RS 422 RXD /RXD
Read only Terminals
RS 422 TXD /TXD RXD /RXD
Master
Use of HMI-Editor V 1.3 (recommended):
Select the terminal:
D230 with 8 x 20 (or D231 or D232)
Terminal topology:
bus
Terminal number:
xx terminals
Terminal list:
just one address (the same as the terminals address)
Serial line:
1
Type of serial line:
RS 422
Baudrate:
up to 19200 bps
Handshake:
None
Connection diagram:
see chapter 2.4