USB Serial converters and RSLinx


Thread Starter

Mike Davis

I am having problems connecting to an AB SLC504 from RSLinx via a Belkin USB to Serial converter and AIC+ PIC interface module.

Anybody out there succeded with this one? If so please let me know your configuration setting and driver configurations.

Regards -

Alan Rimmington

Simple answer is you can not do it (I have spent a long long time trying). The PIC driver timing is not supported, I have even tried a PCMCIA to RS232, and these don't work either. The only way to do it is to change the RS232 port on the processor to DF1 protocol this works fine with the Belkin USB to RS232.

[email protected]
Thanks for your reply Alan.

I have come to the same conclusion as you re-the USB-Serial Converter but I am more interested to hear that you have experienced problems with the PCMCIA card. Was this a 1784-PCMCK card? This is my current avenue of persuit and It will be costly if it fails.


I found this snippet of information in an AB technote -

Keywords: PIC AIC+ ACPI 1747-PIC USB DH-458

There are numerous issues which may prevent successful or sustained communication utilising the 1747-PIC module or 1747-PIC/AIC+ driver. These
issues are not necessarily problems with the PC or software, but most commonly, they are features of newer PC hardware and software that interfere with the operation of the PIC driver.

"Consult the list below and then check the system you're having problems with to determine if anything on the list may apply.

"List of Issues:
1. USB to Serial converters: A USB to Serial converter will NOT work with the PIC driver/module. A standard serial port MUST be used. The converter is not capable of making the necessary timing conversions that the driver requires to got from a DF1 protocol to DH-485. Systems without a COM port and only USB ports must use a 1784-PCMK card. [PCMK - £866.00 15/03/2002]
2. Infrared Ports: Infrared ports found on PCs or notebook computers should be disabled in the system BIOS or setup utility. Infrared ports commonly share resources with the COM ports on the system, thus they prevent the PIC driver from obtaining and using all required resources.
3. Power Management: All power management functions should be disabled in the system BIOS or setup utility. As with Infrared Ports, Power Management may prevent the PIC driver from obtaining and using the necessary resources from
the COM ports. Also, if power management engages while using the PIC driver, the COM port resources may be completely inaccessible until a system reboot.
4. COM Port Settings: These are the proper COM port settings for use with the PIC module/driver. They can be changed through the Windows Control Panel using the Device Manager or in Windows NT, through Ports. Bits/sec - 9600, data bits - 8, Parity - None, 1, Flow Control - None, under "Advanced" - Disable FIFO buffers (un-check the box that says "Use FIFO buffers")
5. ACPI: ACPI stands for Advanced Configuration and Power Interface and is found only on the Windows 2000 and Windows XP operating systems. Not all computers are adversely affected by ACPI, but if necessary, ACPI should be disabled both in the Windows environment and in the system BIOS or setup utility (not all systems have ACPI options in the BIOS). Please consult article A2084 for more information on ACPI.
6. Anti-Virus Software: In extremely rare cases, some anti-virus programs may be monitoring the system COM ports and prevent RSLinx from obtaining the required resources for the PIC driver. Try temporarily disabling the anti-virus software or services.
7. User Privileges: When attempting to configure any driver in RSLinx, local administrative privileges are required. Some drivers may configure without these privileges, but they may not function properly. Once configured, all
drivers can be run from a standard user account. This will only be applicable in a Windows NT or 2000 environment.
8. Hardware Problems: 1747-PIC modules, PC COM ports and serial cables occasionally go bad. If you've tried all the options above and are still
unsuccessful, try switching hardware and/or computers. You may also consider using a 1784-PCMK card (PCMCIA bus) for laptops or either a 1784-PKTX card (PCI bus) or 1784-KTX card (ISA bus) for desktops.
9. Windows XP: At the time this technote was written, there is no support for the 1747-PIC driver on Windows XP."

Best Regards -


Alan Rimmington

No the PCMCIA card is a standard RS232 type, I thought it may work with the PIC driver but alas no. Seems to me AB have a vested interest in selling expensive PCMCIA KT cards ;-). I have found that another option to get on the DH485
network is a 1747-KE card, this allows the DF1 connection to operate on DH485. Let me have your e-mail address and I will share the little knowledge I have.
[email protected]

Larry Lawver


You did not specifically mention the protocol you are trying to use, and the hardware you mentioned could be part of two different architectures.

If you are trying to use the PIC/AIC driver, it won't work under any circumstances I am aware of (painful experience), and as far as I know that is the official line from Rockwell as well.

If you are trying to use the DF1 driver for SLC/Micro, it should work. Rockwell has tested and approved the Belkin F5U103, Keyspan USA-19W, and Keyspan USA-19QW for this purpose. In my experience, I have never had a problem with USB to Serial Converters on DF1.

Hope this helps!

Larry Lawver
Rexel / Central Florida