USB485 USB to RS485 Converter Card User Manual Version 1.00 RMS Technologies 2533 N. Carson St. #4698, Carson City, NV 89706-0147 1-877-301-3609 sales@rmsmotion.com www.rmsmotion.
Thank you for purchasing the USB485 converter card. This product is warranted to be free of manufacturing defects for one (1) year from the date of purchase. DISCLAIMER The information provided in this document is believed to be reliable. However, no responsibility is assumed for any possible inaccuracies or omissions. Specifications are subject to change without notice.
Table of Contents Specifications ................................................................................... 4 Pin Assignments ............................................................................... 4 Installation ....................................................................................... 5 Turning on Echo ............................................................................................... 8 Determining Communications Port Number .....................................
1 Specifications GENERAL • UART I/F Supports 7 / 8 Bit Data, 1 / 2 Stop Bits and Odd/Even/Mark/Space/No Parity • Data rate 300 => 250K Baud • 384 Byte Receive Buffer / 128 Byte Transmit Buffer for high data throughput • Adjustable RX buffer timeout • Auto Transmit Buffer control • Integrated Power-On-Reset circuit • Integrated 6 MHz – 48 MHz clock multiplier PLL • USB 1.1 and USB 2.
3. Installation Please make sure you have the following before proceeding: • • • RMS Technologies USB485 converter. Standard USB Type A to B cable. RMS Technologies Manuals and Software CD. Installing the Unit: The USB485 Converter card will install two sets of drivers. One set is for the unit itself, and the second set is for the Virtual Communications Port (VCP). 1. 2. 3. 4. 5. 6. Power up the PC and start up Windows. Connect the USB485 converter card to the PC with a USB cable.
7. 8. A window will appear asking you to specify driver location. Choose “Don’t search. I will choose the driver to install.” Click “Next” 9. Choose “Universal Serial Bus Controller” under Device Type 10. Choose “Have Disk…” 11. Input the location of the driver files. Typically, this will be on the RMS Technologies Software and Manuals CD. For example: “D:\USB485\DRIVERS” and click “OK.” RMS Technologies USB485 Converter Card 6 Version 1.
12. Select “RMS Motion Serial Converter” from the device list, click “Next”. 13. Select “Continue Anyway” when warned about Windows Logo Testing. RMS Technologies USB485 Converter Card 7 Version 1.
14. Click “Finish.” to complete installation. 15. Once you have clicked “Finish,” Windows should automatically detect another new device. This will begin the installation of the VCP drivers. 16. Repeat steps 5-14 replacing “RMS Motion Serial Converter” with “RMS Motion USB485.” Turning on Echo There is a jumper on the PCB inside the case used to turn on and turn off echo. The Default position of the jumper is on Pin 2 and Pin 3, echo off.
3. Determining Communications Port Number Upon installation, the RMS MOTION USB485 will be assigned a COM PORT number. This number is dependent upon the number of existing COM PORTS already present in your Windows operating system. To determine what COM PORT number the USB485 has been assigned: 1. 2. 3. Right click your “My Computer” icon and choose “Properties.” Select the “Hardware” tab. Click on “Device Manager” RMS Technologies USB485 Converter Card 9 Version 1.
4. In the Device Manager, the following should be listed: a. Under Ports (COM & LPT), there should be listed “RMS Motion USB485 (COMX)” where X is the Communications Port # assigned to the device, it is assigned to COM8 in this example. This setting may be changed and will be discussed in the next section. b. Under Universal Serial Bus controllers, there should be listed “RMS Motion Serial Converter.” RMS Technologies USB485 Converter Card 10 Version 1.
4. Changing the Assigned Communications Port Number Upon installation, the USB485 device will assign itself the lowest free Communications Port number. This setting can be changed to any free communications port that is not in use by Windows. Note: Previously installed devices no longer on the system may cause some COM Ports to be listed as in use. The USB485 may be set to use these numbers, but please be sure that the device previously using the port is disconnected.
4. In the Device Manager, find “RMS Motion USB485” under “Ports (COM & LPT)”. 5. Double click on “RMS Motion USB485” to go to Properties. RMS Technologies USB485 Converter Card 12 Version 1.
6. Select the “Port Settings” Tab and click on “Advanced.” 7. In the Advanced Settings window you may change the assigned COM port number. Click “OK”, and the RMS Motion USB485 is changed to the new COM Port Number. RMS Technologies USB485 Converter Card 13 Version 1.
5. RS485 Communication The Interface The EIA specification RS485 defines an integrated circuit that is to be used to connect up to 32 nodes to a two-wire party line bus that does not exceed 4,000 ft. in length, and for use with data rates up to 10M Baud. The two-wire bus must be terminated at one-end for short wire runs and at both ends if the runs exceed 20 ft. One of the two wires must be biased positive with respect to the other by approximately 700 millivolts.
