getting started

[geneo]

I have a 14M on a breadboard,wired up according to picaxe doc's but my computer (XP) can't see the hardware. When pin 2 is taken high, pin 13 puts out it's little (5V) pulse train: many pulses followed by some sort of character. I can see this on a scope. The picaxe programmer sets com1 to 4800,n,8,1. Have DB9 cable and good 5V PS.:

 

[wojeepster]

is your serial port on com 1?

 

[geneo]

yes device manager say it is.

 

[MPep]

Download circuit is indeed correct?
Many new-comers seem to get this bit wrong. Not necessarily saying that you have though

 

[Rickharris]

It is something simple. Many times we get sudents plugging into the wrong com port (we have 2) - Or PSU wired wrong way round - Try the FAQ trouble shooting list.

 

[manuka]

Some folks just seem cursed with these initial hassles, which naturally can be disheartening! It's often the PC & XP being too smart for themselves, & NOT your fault. Perhaps initially hence grab an old serial fitted laptop- even a W98 oldie will do. Stan

 

[kevrus]

If you are using the USB lead, try doing a 'refresh' from the programming editor with the lead plugged into a USB port, when I do this, it highlights 'com port 5'

 

[moxhamj]

Sometimes you have to go right back to basics. Seems the data is coming out of the com port. Now to test if data is going back into the com port. Grab a D9 female socket, join pins 2 and 3 together and stick it on the end of the serial plug. This is a "loop back" cable, ie what comes out of pin 3 goes back into pin 2. Then run Hyperterminal (it is in the accessories menu). Select your correct com port, pick any baud rate, and then try typing something. It should appear on the screen, which means it went out of the com port and came back again.

If that works, can you double check the wiring of the picaxe - 22k/10k correct (it is not a voltage divider).

If that works, I've still had picaxes recently that appear to be dead. Eg code with setfreq m8 then serin will hang the picaxe and prevent further downloads. Do a hard reset (this is in the manual) - you turn off the power to the picaxe, then do a dowload, then turn on the power when the download bar appears.

And if all that fails, can you pls post a photo of your protoboard.

 

[geneo]

if i go to dos(i love dos) and do a "copy con aux" and i see data coming in to pin 2 on the 14m, which is also wired to pin 3 on the db conn. through a 220 ohm resistor, dosen' that mean that it is com1?

 

[moxhamj]

Yes, it does suggest the com port is working.

So the problem is more likely the picaxe - the supply to the picaxe, the 22k/10k resistors etc.

 

[geneo]

DR ACULA, i did what you said about the hyperterminal test. i just connected the db pins at the breadboard. i got nothing. must be my computer.

 

[inglewoodpete]

When pin 2 is taken high, pin 13 puts out it's little (5V) pulse train: many pulses followed by some sort of character. I can see this on a scope.

That is normal for a PICAXE: It reacts to the serial <Break> signal with a couple of 'bursts' of pulses out of the Serial Out pin. I'd say the PICAXE is behaving correctly.

My (limited) experience with the USB programming lead has shown me that it is more likely to not work on the PC's receive side. So if you get pulses out of the PICAXE, then the problem is the USB cable or, more likely, device driver. Have you loaded the USB download cable driver from the installation disc (or the PICAXE website)? The driver from Prolific did not work for me.

 

[moxhamj]

Even more basic test then. Measure the volts on the output pin of the serial cable (the bit that connects to the junction of the 10k/22k resistors). On a standard male D9 plug on the back of a PC or a USB serial adaptor, the data output line is pin 3 and the ground is pin 5. Do you have something like -9 to -11V?