USB - Serial Adaptor + Picaxe = Problems & I'm Stumped!

[Christopher M. J]

Hey all, i've got problems and I can't for the life of me figure out
how to solve it.

I've got a Picaxe08 controller and board setup I use at school, it
works fine with the computers, they all have serial ports.

Today I went to jaycar and picked up their USB-232 adpator, (cat code
XC4835) I installed it correctly, it detects, everything works, i've
set the com ports correct, but I just can't get it to download
anything I write to the pic.

If I use the terminal function in the PICAXE editor, I can send and
get a response from the pic, I 110% positive everything is wired up
correctly and Im pretty certain the adaptor itself is working.

So i'm pretty much stumped, i've set the PIC jumper to program, I know
everything is in order, but it just doesn't want to work.

I remember another guy at school having troubles with his USB-serial
adaptor, don't know what he done, but I won't get to see him for a
while, so if anyone has any ideas i'd really appreciate it.

 

[m.tiede]

Have a look at picaxe forum. There has been an issue with some usb dongels.
From what I can recall some of the adaptors dont work with the editor.
By the way have you downloaded the patch for the usb adaptor from
the picaxe site?
Also the picaxe 08 will give grief if you have long pauses in the program
that is already burned in.
To overcome this put a dpdt switch between Vcc and pin1 and between
serial in and pin 2.Then when the download frame appears flick the switch
over.
In my experience just disconecting Vcc most times will not work as the
serial in line puts enough power into the chip so it does not power
down.
Then if you have a spare input pin ,put a switch on it.(hooked up per
manual).
Make your first line in your program like this:
here: if pin "switch" = "switched" then here
that way you know your program stays on the first line.
Making downloads less hassle during development.
Then when you finished development remove
the first line and the switch.

Hope this helps
Mathew

 

[TheRealAndy]

Have a look at picaxe forum. There has been an issue with some usb dongels.
From what I can recall some of the adaptors dont work with the editor.
By the way have you downloaded the patch for the usb adaptor from
the picaxe site?
Also the picaxe 08 will give grief if you have long pauses in the program
that is already burned in.
To overcome this put a dpdt switch between Vcc and pin1 and between
serial in and pin 2.Then when the download frame appears flick the switch
over.
In my experience just disconecting Vcc most times will not work as the
serial in line puts enough power into the chip so it does not power
down.
Then if you have a spare input pin ,put a switch on it.(hooked up per
manual).
Make your first line in your program like this:
here: if pin "switch" = "switched" then here
that way you know your program stays on the first line.
Making downloads less hassle during development.
Then when you finished development remove
the first line and the switch.

Hope this helps
Mathew

I hate to give a blatant plug to dontronics (then again, i dont mind since
he doesn't spam the group anymore), but his USB adaptors are pretty good. I
have had grief with plenty, yet this is the first one to do the trick.
http://www.dontronics.com

PS, there is also a trick for winxp that will prevent the USB port being
seen as a serial mouse if you are using streamed data. You will have to do a
google search to find it though.

 

[Christopher M. J]

Thanks for that,

which USB patch were you referring to?

The program burnt in has no pauses, its just putting out a High on one of the pins.

 

[Christopher M. J]

Hmmm, cheers for that. I'm going to see what I can find, otherwise
i'll take the dongle back to Jaycar and order this other one.

I just cant for the life of me figure out what's going out. The PICAXE
editor can see a com port, I can use the terminal command - transmit
and get something from the picaxe. What I notice is when I do this the
TX light on the dongle lights up, and if I have the pin set to program
the RX light goes on aswell.

However when I go to actually transfer a program, nothing happens. No
TX, no RX.

 

[Roger Lascelles]

Dontronics have great USB to serial chips from http://www.ftdichip.com/ .
If an adapter from Dontronics contains this chip, it will also be great.

USB to Serial adapters genarally are a nightmare, but the FTDI people have
ironed out most of the problems.

Roger

 

[Don McKenzie]

Hey all, i've got problems and I can't for the life of me figure out
how to solve it.

I've got a Picaxe08 controller and board setup I use at school, it
works fine with the computers, they all have serial ports.

Today I went to jaycar and picked up their USB-232 adpator, (cat code
XC4835) I installed it correctly, it detects, everything works, i've
set the com ports correct, but I just can't get it to download
anything I write to the pic.

If I use the terminal function in the PICAXE editor, I can send and
get a response from the pic, I 110% positive everything is wired up
correctly and Im pretty certain the adaptor itself is working.

So i'm pretty much stumped, i've set the PIC jumper to program, I know
everything is in order, but it just doesn't want to work.

I remember another guy at school having troubles with his USB-serial
adaptor, don't know what he done, but I won't get to see him for a
while, so if anyone has any ideas i'd really appreciate it.

Christopher,

I too would like to know if the converters I have will work with picaxe.
If you get one from me, and it doesn't work, return it for a full refund.

Cheers Don...


--
Don McKenzie
E-Mail Contact Page: http://www.e-dotcom.com/ecp.php?un=Dontronics

USB to RS232 Converter that works http://www.dontronics.com/usb_232.html
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