PICAXE 18X Memory Verification Error during download

[ceyde]

I'm sure this topic has been discussed already, none of the threads seem to address the problem completely.

I am using

1. A PICAXE 18X
2. A Radio Shack Usb to serial converter 26-183
3. The download circuit from the manual (standard)
4. Windows XP
5. 4 1.2 volt rechargable batteries

When I download in this configuration I get the dreaded "memory verification error" byte XXX, etc, etc

I can NEVER get a program to download in this configuration.


HOWEVER, When I use 2 Standard AA (non-rechargable) ie a 3 volt system, I can get it to download and run 75% of the time. after retrying the download a couple of times I can always get it to work.




Recaping 4.8 Volts never works for download, 3.0 volts almost always works for downloading.

Suggestions?

 

[inglewoodpete]

The 18X can be difficult to program at times. Personally, I have not had any trouble with them but I don't use the USB to serial cable.

Note that the USB cable will only output 5v logic and this may be the cause of the problem. "Normal" serial cables use RS232 (+12 to -12v) electrical protocol. Try different supply voltages on the PICAXE when downloading: there may be a 'sweet spot' or 'zone'.

Some of our gurus have trouble with the 18X and USB cable: refer to this thread by BeanieBots

 

[BeanieBots]

It certainly is a function of supply voltage.
4 x 1.2v (nominal) cells will nearly always be greater than 5v.
In fact, fresh off the charger, they could easily give close to 6v.

I must add that since changing from the USB010 to the AXE027 I have NOT had any verification errors.

 

[hippy]

Welcome to the PICAXE forum.

4 x AA can give a too high voltage, 2 x AA is below the official operating voltage of the 18X ... have you tried with 3 x AA ?