Specifications

QuickMedia Receiver/Processor Crestron QM-RMCRX
Troubleshooting Communications
Use the following checklist if communication cannot be established with the
QM-RMCRX.
1. Verify that you are using the correct cables. As described previously,
an RS-232 connection requires a null modem RS-232 cable with DB9
female connectors on both ends. TCP/IP connection requires a CAT5
cable with 8-pin RJ-45 connectors.
2. With a serial connection, verify that the correct COM port on the PC
has been selected. Some computers have more than one COM port;
some may be internal (e.g., for a modem). Consult the manufacturer’s
documentation for further information about the COM ports on your
PC.
3. Ensure that you have a serial connection to Port B, and reset the control
system as follows:
a. Open Viewport and click Setup | Communications Settings to
display the “Port Settings” window. Choose RS-232 as the
connection type.
b. Set the baud rate of the PC to 115200.
c. Set the baud rate of the QM-RMCRX control system to 115200, as
follows:
- Press and release the HW-R button on the unit’s front panel.
- Press and hold the SW-R button for approximately three to
five seconds. The Viewport console should display the
following message:
Viewport Message
QMRMCRX>
Control Console
Changing to default Comm Specs. 115200 N81 RTS/CTS
Switch to new settings….
Bypassing Program Load!!!
- Release the SW-R button.
d. If communication still cannot be established:
- Remove power from the control system.
- Press and hold the SW-R button on the front panel of the QM-
RMCRX.
- Reapply power to the control system.
- The Viewport console should display the message shown
above.
- Release the SW-R button.
e. Select Set Baud Rate on the Viewport Functions menu (or press
F8) and choose any baud rate from the drop-down list. This will
attempt to establish a connection at the indicated baud rate. If the
connection is successful, both the PC and the control system will
be set to the new baud rate. The QM-RMCRX will return to its
original communication settings when the program reinitializes.
22 • QuickMedia Receiver/Processor: QM-RMCRX Operations Guide - DOC. 6236