Specifications
C2-6104A OPERATION MANUAL
47
9 SERIAL PORT
9.1 Connection
Your unit is fitted with a standard ‘D9’ plug or socket allowing it to be controlled from 
a computer or other type of terminal or console with a similar interface. Most 
computers fitted with an RS232 port, known as a ‘COM’ port, will have a ‘D9’ plug 
on them. To enable connection between the two devices you will require one of two 
cables as shown below:
D9 connector type
on C2 unit
RS232 cable type required
for linking to PC
Plug – common on earlier C2 units ‘Null-modem’ D9 socket to socket
Socket – common on recent C2 units D9 plug to socket
Should your PC not have an RS232/COM port, it is possible to add an interface 
card into the PC to add this facility. Another option you could use is a USB to 
RS232 converter. Both methods will add a COM port to your PC, although you 
should be aware that these generally do not default to being ‘COM1’ which is the 
default most RS232 applications will use.
Some units are also RS-422/485 capable – see the Specifications section for more 
details.
The default baud rate is 57600 with 8 data bits, 1 stop bit and no parity. This baud 
rate can be changed in the System menu to suit other programs if need be.
9.2 Communications protocol
The standard communications protocol for your unit is text-based and is detailed on 
our website. Also on our website, you can find the Windows Control Panel or 
CORIO®tool Suite for your unit.
The protocol is also bi-directional (unit and computer both send messages to each 
other), so that you can send changes to the unit, and it will also respond with any 
changes made via alternate methods (front panel buttons, menu changes and infra-
red control). This enables any attached computer to be aware of any changes 
made to the unit from an alternative source rather than itself.
What this means is that you can easily find out the exact command to send to the 
unit to tell it to perform a certain function. This can be seen by the data that is sent 
back to the computer when changing values on the unit. For instance, just by 
turning FREEZE on, by pressing the FREEZE button, will cause RS232 data to be 
sent to the computer that represents the command required to set FREEZE on. A 
second press, to turn FREEZE off, then sends the computer the command required 
to turn the FREEZE off.










