THOMSON REMOTE COMMUNICATION - V3.0 User Manual page 39

SECTION 2
The signal-type indicates the type of physical connection between the host and
CIM. The RS-232/Modem option indicates that a connection is via a standard
RS-232 cable or the internal modem (CIM Port 1). The RS-422 and RS-485
options are for multi-drop networks. The auto-detect option will allow the CIM to
attempt to decide for itself which physical connection is in use. The default
signal-type is auto-detect.
The other parameters are standard serial type parameters, including parity, data
bit size, stop bits and baudrate. The baudrate values can be 1200, 2400, 4800,
9600, 14400 and 19200. The receive-timeout parameter describes the amount of
time after receiving the last byte of the packet until the packet is processed
internally.
The Restore Defaults button will restore all parameters to their initial values,
which are no parity, 8 data bits, 1 stop bit, 9600 baud and 20 millisecond receive-
timeout.
The Fixed Modbus Mode option is for enabling the fixed Modbus mode for
operation with a Programmable Logic Controller (PLC). Once in fixed Modbus
mode, the CIM no longer requires a password to login, it is essentially always
logged-in to save the PLC from having to do so. All modem functions are
disabled when in fixed Modbus mode as well, to prevent unauthorized remote
access. The only way to disable fixed Modbus mode is to connect directly (via
RS-232 or RS-485) with THS 2000, which will disable fixed Modbus mode when
attempting to log in to the CIM.
Note: the receive-timeout and auto-detect signal-type features were not
supported in previous versions of the CIM and therefore their values appears
grayed-out and read-only when examined by THS 2000.
The protocol used on Port 2 is Modbus, as described in
3.4.6. CIM Port 3
The Port 3 of the CIM is used to communicate with the controllers on the site.
The parameters for this port can be found under the CIM Port 3 tab in the Current
Site Properties dialog box, as shown here.
PM055 Rev 2 00/08/31
THS 2000 SOFTWARE PROGRAM
33
Section 3.
Thomson Technology