Memory verification failed

[Maleny]

If I plug my breadboard with only an 08M on it, via a serial to USB adapter into my laptop which is running editor ver. 5.1.3 and download a simple program all is well. If I plug the same board, same adapter and same power supply into my desktop now running ver. 5.3.3 all I can get is Memory verification failed (at around 240 bytes usually but it varies).

On the desktop I have tried:
1. An AXE027 but I could never get it to work even though it was tested as OK by the supplier and I downloaded and reinstalled the driver several times
2. Four new chips
3. Different USB ports
4. Updating the editor
5. Reinstalling the adapter software

The firmware verification works OK but I can't even clear the memory. So if it's not the chips, the breadboard, the adapter, the power supply, the adapter software or the USB port what could it be?

 

[westaust55]

A common cause of failure for a program to download when the firmware version of the PICAXE is being reported is a supply voltage that is a bit low - albeit that I have operated 08M's down to 3V supply (and via an AXE027 cable).


You say for the laptop you have used the via a "serial to USB adapter into my laptop".
Is this the AXE010 cable?
Or some proprietary adapter module in which case, with what cable?

With the PC you say you have used 4 different USB ports.
For each different port you MUST insstall the drivers.
Have you done that?

Certainly most folks do not have problems with the AXE027 cable with the PE up to the currently latest version.

Which version of windows is running on the lap top and the PC?

 

[slimplynth]

Hi Maleny, that sounds like a complicated set of possible problems. When i've had that error previously it was because i'd moved a circuit from breadboard to vero and if the batteries need changing.. i think.. i like having a rev-ed demo board to hand when problems like this arise because it rules out my design/setup. sorry, i've not been much help.

 

[hippy]

It's frustrating when it all works on one machine but not on another, and it's also difficult to determine why. Assuming the PICAXE hardware works, the Programming Editor works ( there should be no fundamental difference in the downloader between 5.1.3 and 5.3.3 ), that points to something different between the PC's or that something different having an affect on the hardware or Programming Editor.

You indicate that you cannot get the AXE027 working on the desktop PC, so one question, as westaust55 raises, is what cable are you using on the desktop, and which cable are you using on the laptop.

Also what is the circuit the PICAXE using ? It is possible possible that one could have a circuit which works with one PC and cable but not, or less reliably, with another.

Though it's understandable that you don't want to make a situation worse than it is, if you have a backup of the 5.1.3 BAS805.EXE installation, you could upgrade the laptop to 5.3.3 and see how that fares, or find another PC or laptop and try that. That may help to narrow down what the issue is and/or give you confidence the AXE027 does work. As an alternative, you could also install WinAXEpad ( which will coexist with 5.1.3 and 5.3.3 without changing those ) and see what results you get with that.

 

[Maleny]

More info

1 The voltage is 4.5 volts
2 I am using the same USB to serial adapter for both computers
3 I am using the ports which device manager allocates and for which it tells me the driver is loaded and that the device is working correctly
4 The adapter is made by Prolific Technologies
5 I am running XP on both computers
6 I am using the enhanced download cct in both cases

 

[slimplynth]

I gave up on trying to get the prolific usb working. It would only program a 28x2, Hippy was right, too many hoops to Junp through, was quicker to build a new desktop. I thought you were using the axe027 cable Maleny... Other people do use the prolific adapters found on fleabay, mine worked perfectly on a previous laptop running win7... Xp on this asus though

 

[hippy]

If you cannot get the USB010 nor AXE027 cables working nor working reliably with the desktop it does seem the problem could lie with the desktop PC or its configuration rather than elsewhere.

Beyond the things already mentioned I can't really think of what more to suggest. You could try an AXE026 cable or build one and see if things work using a physical COM port and RS232.

 

[Maleny]

Since my last post I have tried the serial port on my desktop (there is only one which is COM port 1) I simply removing the USB serial adapter and plugging the 9 pin D plug directly into the port.
Device manager tells me the device is working OK with the Microsoft driver loaded and the editor tell me COM 1 is ready for use however when I try to do a download the editor tells me that the port is not present or already in use. I don't know if these two problems have the same cause but I will be happy if I could get either working.