Problem with USB to serial programmer

[jimruxton]

Hello,

I'm trying to use an off the shelf USB to serial interface to program a Picaxe 28x1. I can't seem to connect to the Picaxe. . If I use the latest pl2303 driver off the Prolific site when I try "run" the program just locks up and uses almost 100% of my cpu. If I use the pl2303 driver from the rev-ed site the editor doesn't lock up but I get a hardware not found message. Has anyone got an off the shelf Prolific USB to serial interface to work with a picaxe. I have heard some people on the list say that the signal needs to be inverted but I don't understand why if one can use a standard serial port and not have to invert the signal. Can anyone shed some light on what I may be doing wrong?. I have serout from the adapter (pin 3) going through the standard 22k/10k resistor pair into pin 6 and serin (pin 2) from the adapter going to serout , pin 7 of the Picaxe. Thanks for any help

 

[hippy]

Ignore the inversion issue; if this is a standard USB-to-serial ( USB plug to 9-way D ) then it should work as is, providing it is compatible with the PICAXE, that is it allows 'break signalling'.

Given the Rev-Ed driver performs best I would select that to start with. Then try the serial port tests available under View->Options of the Programming Editor.

 

[jimruxton]

Thans for the info. I tried the test option. The serout from the adapter stayed at 5 volts. Does this mean it doesn't support the "break " protocol. This would be strange because it is a pl2303 and I am using the Rev-Ed driver. I know the adapter is working beause using the termnal and connecting serin and serout of the adapter together , characters sent out come back in ?? Strange .. I have never had so much trouble with using a USB to serial adaptor in the past and I've used them on many pic based projects

 

[westaust55]

The Rev Ed AXE027 USB to serial (stereo plug) uses the FTDI USB<>serial converter chip.


However if it is a USB to 9-pin serial connector similar to the AXE010 then yes the Prolific driver is correct.


Have you checked at Control Panel / System / Hardware / Device Manager / Ports

and set the PE to the correct COM port?

 

[jimruxton]

Thanks, Yes I set the port correctly. I tried the terminal prgram in the editor and it worked when I connected the serout and serin of the adaptor together.

 

[tarzan]

Keyspan high speed USB to serial adapter

Hi Jim

Are you using the keyspan high speed USB to serial adapter with linux as mentioned in your other thread or some other device? To me it&#8217;s still unclear which &#8220;off the shelf&#8221; device you have. Please provide details about the device.

• Manufacture
• Model
• Place of purchase (web link)
• Picture
• Nature of connection (home made cable?)

Drivers for Keyspan
http://keyspan.com/downloads/homepage_pn_usa19hs.spml
Keyspan Product Fact Sheet
http://www.keyspan.com/products/usa19hs/downloads/pdf/USA19HS_v1b.pdf
Requirements
Linux :
At least one available USB port; Linux 2.4.22 or greater
Forum member reports success with Keyspan on XP and VISTA
http://www.picaxeforum.co.uk/showpost.php?p=84362&postcount=14

 

[inglewoodpete]

I got caught the same way. You can transmit to the PICAXE but the return data (pulses etc) does not get back to the PC.

Don't use the driver off the Prolific website. Uninstal it and then load the driver from the Rev-Ed CD or website.