I have a multimeter that I try to use to debug, but it doesn't feel like a very good method...



I was concerned that my write cycles were too short; I added some delays here and there but it didn't help.
It may also be that I'm not doing the I/O extender write operation properly, I'll have to look into that in more detail.

_________________
Aspiring homebrew- and replica builder.
Blog http://tobier.se
Hackaday http://hackaday.io/tobier

Turned out my issue was due to some damage my arduino suffered during a previous project. Picked up another one this afternoon and everything is working fine now.

At the least, you should invest in a good logic probe. If your finances allow it, a 'scope is often a big help in figuring out why something doesn't work.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Thanks for the tip! A 'scope is a bit out of my price range for the occasional hobby projects, and I don't really have room for one either, but a logic probe shouldn't be a problem at all.

_________________
Aspiring homebrew- and replica builder.
Blog http://tobier.se
Hackaday http://hackaday.io/tobier

Is a logic probe something that one could reasonably put together oneself on the cheap, or is getting a used probe off of ebay or at an electronics swap meet a better use of one's time and money?


I forget how much I paid for my 'scope, but ISTR it being high-double-digits of USD. A used four-channel 200MHz Tektronics, if memory serves (it's about 60 miles away from me right now, so I can't easily check), with the fourth channel input capped off for some reason, and one of the knobs missing. I've only really used the one channel so far anyway. The probe that came with it was junk, so getting more probes was a bit of a priority, but there are guides out there to making your own cheap probes... (Part of me is thinking "it's only $100, where's the problem", while another part is remembering that there was a time in my life when $100 was a lot of money.)

Or you could go the really-cheap route and use any of the various "arduino oscilloscope" projects out there, but if you do you should be aware that the bandwidth is crap, the inputs aren't the nice high-impedance inputs, and so on. Probably not worth the bother.

I can't really make any suggestions on the space thing, I'm struggling with that one myself.

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

You could build one and, in fact, I have a schematic somewhere around here for a logic probe design that is (theoretically) good to at least 20 MHz.

That said, there are some instances where your time is worth more than the money saved rolling your own. I'd shop around for one, as reasonably good probes aren't too expensive. I did all the debugging on POC V1.0 with nothing more than a logic probe, even though I do have a scope.

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

Since we're on the topic of oscilloscopes, do you think that I could use my Vantage Pro for low MHz digital design and diagnostics? It can do up to 8M samples/sec, but I'm not so sure that the probes supplied for automotive use would be suitable. Maybe I'll fire up my Apple //e one of these days and start poking around to see what happens ... if I accidentally kill it, it wouldn't be the end of the world, and at least my curiosity would be satisfied.

Mike

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Ok, I haven't had a chance to test the new board design with 27SF512 chips yet, but I have tested it with 28C256 chips and it still works for them. I'll call that good enough to pop it back up for sale. For the record there were 8 people listed as waiting for it to come back in stock, and I only made 10. The price of this version is a bit higher, it's a lot more work to assemble (and I'm still selling them fully assembled/tested (aside from the voltage booster till I can get one of those chips)) and there are more components that I had to buy for it. But the price is still pretty reasonable. So anyways, it might sell out pretty quick again.
https://www.tindie.com/products/UnaCloc ... r-arduino/
Make sure you get the latest Java app and Arduino sketch from rpress's Github fork, to ensure compatibility with the new PCB.

I know this thread has not seen much activity but... amazing work!

I am having a few issues biulding my programer.
I don't plan to use the pre-made sheild but rather make my own.

First issue is that no matter what Arduino firmware I use.
Mario's or Rpress's I get issues.
It "seems' like the GUI can not see the device.

With Mario's FW and his version of Simple JBurn 2 I get :

With Rpress's FW and his version of Simple JBurn 2 I get a seg fault (when selecting EEPROM size)

I know my Arduino is plugged in. I can program it via the Ardino software.
I can also see it in lsusb:


So if i run it via the Arduino serial monitor and send the "V" command for version I get :


So confused

Any hints or susgestions ?

What OS are you using?

Does your OS require the installation of librxtx?

I built on of these programmers a few months ago and couldn't get JBurn to work on 64 bit Windows. So I ported Mario's software to C# and got it working. If this is your problem I can point you to my git repo.

Here's my fork of Mario's repo with a new sub-directory called WindowsJBurn

https://github.com/Martin-H1/MEEPROMMER

Hi Martin_H,

I did see your fork on github nice job.
I am using Linux, so that wont be much help for me.

I have the 64bit RXTX libraries installed... I wonder if it depends on the 32bit.
I know someone did a lot more work on the python script.. I may turn to that rather the the UI but I would like to test with the UI to ensure its working as designed.

Presumably this runs via a serial USB device.. do you have user access to the /dev/ttyUSB* device? That the Arduino tool has access could be that it's suid root or sgid a group with access.
It's a shot in the dark of course, but it's the most common problem for Linux users when working with the Propeller, for example.

-Tor

Hi Tor,
My user has access to the tty devices. However even as root I get the same issue
Thanks anyways