To configure the 485LDRC9 to the appropriate baud rate (38.4Kbaud), a set of dip switches must be configured. These switches can be found on the side of the converter. The first four switches should be in the ON position to indicate that the communications are half-duplex. The fifth switch should also be in the OFF position as this activates the 120 Ohm termination resistor within the converter. This terminator is only useful for long RS-485 buses, or other calculated circumstances. Finally, switches six, seven, and eight should be set to the OFF position to indicate the correct baud rate. (Note: An 8.2 K resistor (R11) has been installed at the factory to achieve these higher baud rates. If you did not purchase the converter from the factory, you will need to install the resistor.)
To wire power to the 485LDRC9, place a +10 to 30 VDC supply to terminal F, and place the ground (V-) to terminal C.
The final step in installing the converter is to attach a DB-9 RS-232 (serial) cable from the converter to an available serial port on your computer.
Note The RS-485 bus is half-duplex. If the Base Radio in the application is wired to a RS-
485 to RS-232 converter, the A (Tx+/Rx+) and B (Tx-/Rx-) wires may need to be crossed for correct operation. Please see the converter’s manual for further instructions.
3.2.5Wiring the RS-485/USB Converter to the Base Radio
Note The RS-485 cable should NOT be connected to the RS-485/USB converter before the converter drivers have been installed.
Honeywell also offers a non-optically isolated RS-485 to USB converter. The USB Converter provides easy connectivity between the PC and standard communication ports, not requiring PC reconfiguration, assignment of IRQs, or jumper settings.
Use of this device requires a PC with a USB port compliant with USB 1.1 or later.
The RS-485 to USB converter is equipped with a USB cable and a USB type A connector for connection to a PC USB port and a male DB-9 for connection to an RS-485 equipped data or communication terminal.
3.2.5.1USB Driver Installation
1.Power on the PC. Verify the USB port is enabled and insert the CD that has been provided.
2.Connect the USB cable of the converter to the USB port of the PC. Make sure not to have the RS-485 cable plugged into the converter at this time.
3.Windows™ should detect the USB device, and if the driver does not already exist on the PC the “Add New Hardware Wizard” will be displayed. Click the NEXT button.
4.From this new screen select “Specify a Location” and specify the PC’s drive letter for the CD-ROM drive where the provided CD has been inserted. Click the NEXT button to begin the search.
5.Once the drivers have been located a new screen will be displayed. Click NEXT to continue.
6.At this point Windows™ has finished installing the RS-485 to USB converter drivers. Click FINISH.
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