RS232 to USB Cables That Work (Or Don't)

Started by Andy Ayre, January 24, 2007, 11:17:38 AM

Previous topic - Next topic

Andy Ayre

This thread will be used to compile a list of RS232 to USB cables that work with Flash Magic and NXP microcontroller bootloaders. If you have one please post the details.
Embedded Systems Academy, Inc.
support at esacademy dot com

Andy Ayre

First report of a working cable:

On the cable itself and the package are not much of markings, looks like no name. So best clues I can give is through the driver:

Driver installation mentioned a "PL-2303"
The Device manager identifies it as "Prolific USB-to-Serial Comm Port"
With driver name being "Prolific" and version ""
Seems to work fine with W2k, on-board USB1.0 and PCMCIA USB 2,0 adapter.

With Flash magic I was able to detect the MCB2100 and flash the CANopen bootloader.
Embedded Systems Academy, Inc.
support at esacademy dot com

Jan Waclawek

Can you please check it also with other chips?

PL2303X was found to be not working satisfactorily - this has to do with the way how the '51RD2's bootloader sends out the characters (with no space between them); so also the crystal, associated level converters and cabling will influence the chances of this gadget working or not.

[added later] A similar, but PL2303HX-based cable was found to be working OK.
It appears, that there are different versions of the PL2303 with different suffixes; and also different revisions of the same suffix chip. Also, the reason of non-working of certain revisions might perhaps be different than the chip itself, so no definitive conclusion can be drawn at the moment based on "PL2303-based" alone.


Andy Ayre

Here is a report of a cable that doesn't work from a Flash Magic user. They were programming an LPC2378 using Flash Magic 3.50.

QuoteI found out that when using FlashMagic, I have to connect to a regular com port on my PC. Using an USB/RS232 converter (Eminent) did not work. It took me 2 weeks before I found out that this converter was the cause of my problem.
Embedded Systems Academy, Inc.
support at esacademy dot com


I have two of the older cable from radioshack part number 26-183, but now when I search for that there is a new catalog number 26-949.

They look exactly the same in shape, but older one is white, new one is black.  Not sure if the internals are identical or not.  But the two older ones if still can be found, work fine on the LPC 924 and 936.  I also use it for my home automation system Crestron.

Hope this helps some.



I did single face circuit board based LPC900 programmer circuit from Elektor

the Elektor printed circuit is double face.

I sucessfully programed P89LPC9221 using USB - Serial  T1=120ms T2=120ms baund rate = 7200

Prolific PL-2303 driver ver date 07/16/2003

FM current and Windows XP sp2