Serial interface

fingerae

I have set up a Propeller to serial port circuit as seen in

http://www.parallax.com/Portals/0/Downloads/docs/prod/prop/SerialtoPropeller.pdf

I then connect the serial plug to a Radioshack 26-183 USB to serial cable.· When I search for the propeller chip using the Propeller Tool V1.2, it cannot identify the presence of the propeller chip.· It does, however recognize the Radioshack USB to Serial cable.· I have the Radioshack USB to Serial cable settings as follows:

Bps:· 9600
Data bits:· 8
Parity:· None
Stop bits:· 1
Flow control:· None

Any thoughts about what I might be doing wrong?

Thanks.

Mike Green

The RadioShack USB to serial cable is known not to work for programming a Propeller (or a Stamp for that matter). The problem is that it doesn't properly implement the DTR handshaking signal which the Propeller and Propeller Tool need to reset the Propeller so the bootloader gets control at the proper time. Pretty much any USB to serial adapter using the FTDI chip should work (including the ones Parallax sells) and the Keyspan High Speed Serial Adapter works.

fingerae

Thanks.· Is that the case for most USB to serial cables?· I've also tried a GoldX cable from Prolific with similar results.· I have used it for several years programming a BS2 successfully, but the Propeller is not recognized.

fisio

In our home page called Elettronicamente
you must register and then download
our tutorials on chip FT232,
we designed and built a module to be mounted
in any circuit that requires the conversion USB/232:

Introduzione al convertitore USB <-> RS232 FT232BM (introduction to USB converter)
http://www.elettronicamente.com/engine/default.asp?page=projectdownload&pid=333

Interfaccia convertitore USB <-> RS232 (Rev.2) (USB converter),
http://www.elettronicamente.com/engine/default.asp?page=projectview&pid=338

Il modulo ELFT232-M (the module ELFT232-M)
http://www.elettronicamente.com/engine/default.asp?page=projectdownload&pid=334

Costruzione del modulo ELFT232-M (how made the ELFT232-M module)
http://www.elettronicamente.com/engine/default.asp?page=projectdownload&pid=458

The interface·is USB/TTL 5 volts, we must adapt the signal at 3.3 volts)

Bye

Fisio
www.elettronicamente.com


Post Edited (fisio) : 11/2/2008 11:05:12 PM GMT

Mike Green

There's no list of acceptable USB to serial adapters for use with the Propeller nor, for that matter, for use with a Stamp. I suspect that it's too expensive to acquire and test all the USB to serial adapters that are available and continue to crop up, particularly when Parallax has very inexpensive adapters that are known to work and others that use the FTDI chips are also known to work.