Matchbox sized 6502 / Z80 / 6809 Co Pro

[hoglet]

Thanks, that build seems 100% reliable on the rev E RAM.

Great.

Can I ask which Co Processors you were able to test?

Dave

[flynnjs]

I checked each would boot and at minimum issued some star commands.
In the case of Z80 I also ran BASIC
In the case of x86 I also ran DOS

I didn't get time to exercise the paged RAM on 6502.

[firthmj]

Does that mean you would recommend this build if people are upgrading?

[flynnjs]

If you have RAM ending in EBLL, yes, you most definitely need to.

If you have RAM with DBLL then you may get away with slightly more aggressive speeds and use Dave's Nov '16 build.

[BigEd]

Glad you got it working Jason! It seemed to be quite the puzzle when I dropped by.

[firthmj]

Hi,

I've updated my CoPro this evening, and I'm seeing the dynamic mode switching lock up quite often

I've tried both the latest (LX9CoProCombined_20170514_1320_dmb) and previous stable (LX9CoProCombined_20161110_1455_dmb) designs, and both seem to behave similarly

It appears to only happen (so far) with the 6502 design.

The symptom is to switch between the various speeds of that and the NULL design (modes 0,1,2,3 and 14 in the firmware builds I'm using)

After a few such switches, the 6502 mode will "jam on", and it won't be possible to switch modes via the soft reconfiguration any more.

Reloading an old boot loader design .bit file with JTAG unlocks the switching for a while, but it will always lock up again quite quickly.

Switching between the ARM and NULL designs (12 and 14) doesn't seem to have the same problem.

Has anyone else seen this?

Is there anything different about the 6502 design that may make the dynamic switching less stable in it?

Thanks

[flynnjs]

I've just soldered up a board for myself this evening (as I haven't had one for months!).

After programming it and testing it, I too noticed that and was mulling over why this
board was doing something that I hadn't seen this weekend.

Many of the boards I tested at Cambridge were defaulting to something other than
the 4MHz 6502 which may explain me not spotting it.

[hoglet]

Hello all,

There is a new release of the Matchbox firmware available (20171003_0811):
https://github.com/hoglet67/CoPro6502/releases

I've also added all the significant past releases, so they are together in one place. For reference, most of Jason's boards shipped with the "20151215_1004" release.

Here's a quick summary of the changes:
- Co Pro 6502: updated speeds to 3, 4, 16, 64 MHz
- Co Pro 6809: Updated Client ROM to v1.05
- Co Pro PDP11: Updated Client ROM to v0.27a
- Be more conservative with timing within ICAP_core (might address some unreliability with *FX 151,230,N)

I'd be interested in feedback on the last item from anyone who has been having issues switching between different co processors.

Dave

[RobC]

I'd be interested in feedback on the last item from anyone who has been having issues switching between different co processors.

Just upgraded my Matchbox boards. I have one of the red boards with decoupling mod and am using a 3-inch cable.

On my BBC B, switching between co-pros is okay apart from when switching from the ARM Co-pro (12) to something else. It seems to get stuck in the ARM copro and generally doesn't want to switch to anything else. This seems similar to what I was finding with the previous build.

On my Master 128, switching is better although it still gets stuck in the ARM Copro sometimes. However, it does seem better than the previous build as that seemed to get stuck most of the time.

[hoglet]

Hi Rob,

On my BBC B, switching between co-pros is okay apart from when switching from the ARM Co-pro (12) to something else. It seems to get stuck in the ARM copro and generally doesn't want to switch to anything else. This seems similar to what I was finding with the previous build.

Right, I've tracked down the reason the that the ARM2 Co Pro gets stuck, and I might be able to fix that. It's an issue that is specific to just that Co Pro.

Do you have any issues switching between any of the other Co Pros?

A good test is to program some of the function keys with *FX 151,230,N, and then that allows you to try lots of switching quite quickly.

Dave

[RobC]

Hi Dave,

Not seen any problems switching between the other copros but I'll stress test it tomorrow.

[hoglet]

Hi Rob,

Not seen any problems switching between the other copros but I'll stress test it tomorrow.

I've just pushed a new release (20171007_0719) that I hope will improve the configuration unreliability.
https://github.com/hoglet67/CoPro6502/releases

Please let me know if this resolves all the issues you are seeing.

Dave

[RobC]

Hi Dave,

Just tested that release on my BBC 'B' and it all looks good

Changing from the ARM co-pro now works reliably - I spent 10 minutes flipping between processors and didn't see it fail once

Haven't tested it on a Master yet but, given the Beeb displayed the problem most often, I suspect all will be well.

Thanks,

Rob

[hoglet]

Just tested that release on my BBC 'B' and it all looks good

Changing from the ARM co-pro now works reliably - I spent 10 minutes flipping between processors and didn't see it fail once

Excellent, thanks for testing it out.

Dave

[trixster]

I'd like to update the firmware on my matchbox coprocessor but I'm not sure how. This might be a little cheeky but if I were to post it to one of you guys would you be able to flash it for me? I'd cover p&p both ways and pay for beer!

[RobC]

This might be a little cheeky but if I were to post it to one of you guys would you be able to flash it for me?

Happy to do it for you. Send me a PM and we can arrange things.

Cheers,

Rob

[trixster]

Thanks rob, I'll PM you.

[trixster]

Thanks for flashing my copro Rob, works great! 3mhz 6502 now for tubeelite

[vanekp]

Received my Matchbox LX9CoPro today seem to work okay at first but then started playing up after a while *sigh*

20171020_211217.jpg

20171021_185117.jpg

Also noticed the switches seem to work in reverse as 14 or 1110 should be CoPro off but as you see I have to set 0001 for the CoPro to be off is the switch mounted upside down on the board?

20171021_184015.jpg

I was having problems yesterday with Pi3 CoPro but that one seems to work fine, am just wondering if there is something inside the socket from the new CoPro that’s causing it not to make good contact.
At one point it was working find then I removed it to change the switch to default the CoPro to always be off then it started playing up again.
When its faulty it does not matter if I run Elite on 3Mhz 16Mhz or 64Mhz CoPro.

[paulv]

That looks reminiscent of my Beeb with Elite on a ReCo 6502 2nd processor

viewtopic.php?f=3&t=3901&start=30#p33921

which is also talked about in this thread...

http://www.stardot.org.uk/forums/viewto ... f=3&t=4784

At the time, the ReCo performed flawlessly on all the other machines I tried it on so the fault is definitely with the Beeb rather than the co-pro. Given my resolution which wasn't really a resolution was to keep the machine cool, I just have a feeling that the real resolution will be down to timing sensitive IC's with particular brand combinations of certain chips causing this issue.

Paul

[vanekp]

Did not mention but yes I am using it in an issue 7 BBC, mine does have the new style video processor (no heatsink on it & mod on board to invert video for mode 7).
Odd think is now my BBC has been on for a while with Elite running all the time it has not gone wrong not since my post, but was beginning to think I am having temperature related problems.
The tube port connections look ok and can tap the board while running and it does not crash.

20171021_185252.jpg

O I do have a fan to cool the PSU which draws its air out the BBC side maybe that helps as I find the PSU's on the BBC generate far too much heat.
Peter.

[vanekp]

Last night after a while it ran for hours once it had warmed up, this AM I switch the BBC Micro on it ran for a bit without a problem then the chaos started again
Seems the device is not suitable to use in a standard BBC, certainly is not reliable if it’s going to do things like this

20171022_094709.jpg

[BigEd]

Do you have a multimeter or other way to check that the Beeb's power supply is putting out a healthy 5 volts?

[vanekp]

5.00V on the cap C26 and on the tube connector 4.96V
BBC has been off for a while now it runs fine...for a bit I think so seems more of a temperature related problem than voltage but will check it again when it starts to go wrong.
Peter.

[BigEd]

If you have any cold spray you could explore to see which part is suffering from heat. Or maybe a finger will tell you that.
https://www.maplin.co.uk/p/maplin-freez ... 00ml-n68an

[vanekp]

if you read the post from Paul further up viewtopic.php?f=3&t=3901&start=30#p33921he seems to think it’s the vidoe ULA that’s causing the problem, odd that’s its only when you use the 2nd Processor. Sorry don't have any cooling spray to try to narrow it down or confirm that it’s the video ULA.

[hoglet]

These sort of issues are very difficult to resolve, especially if you haven't got other Beebs you can test with.

While it is possible it's this particular Matchbox that is flaky, about 100 of these have shipped now and most of the reproducible problems in the field early on were down to inadequate decoupling on the first revision of the board. You have the second revision with additional decoupling capacitors.

What's the history of your Matchbox? i.e. where/when did you buy it and do you know what firmware version it contains?

There is a list of firmware releases here:
https://github.com/hoglet67/CoPro6502/releases

There are a few things you could try, to see if they make the problem better or worse:
- give the tube connector a really good clean (ideally with a fibreglass pencil)
- try plugging the Matchbox directly into the tube connector with no cable (it's a bit fiddly to get out again, using a small screwdriver helps)
- disconnect the fan from your Beeb (it's possible this is an additional source of electrical noise)
- try running without the RAM/ROM board (it's the first time I have seen this model, this is a real long shot)
- try swapping the 6502 (if you have a spare)

Dave

[vanekp]

I bought if from flynnjs http://www.sundby.com/index.php/project/matchbox/
its a rev. "A" I would not know what revision the firmware is, how do I see that?
I did post a pic here of it

Also still curious about the switches as I commented that they seem to work in reverse to how they should work.
Have let my BBC cool down and put the Pi3 CoPro on some 30min ago, its been running Elite without a problem also at 64Mhz which is starting to indicate the problem lies with the LxCoPro itself and not my BBC, O and the Pi is being powered from the use port.
And I only have been running it with the LxCoPro directly pluged into the user port.
The fan is runnig off the 12v line not the 5v.

[hoglet]

I bought if from flynnjs http://www.sundby.com/index.php/project/matchbox/
its a rev. "A" I would not know what revision the firmware is, how do I see that?

There is no easy way to tell from the hardware, you'll need to ask Jason.

Also still curious about the switches as I commented that they seem to work in reverse to how they should work.

I'm assuming you have your board configured to Co Pro 14 (the Null Co Pro) in the picture.

That seems consistent with the documentation:
https://github.com/hoglet67/CoPro6502/w ... h-settings

Please read the notes at the bottom, especially:
- A "0" is generated when the DIP switch is ON (the corresponding input is connected by the switch to 0V)
- A "1" is generated when the DIP switch is OFF (the corresponding input pulled up to 3V3 through a resistor)

Is that consistent with what you are seeing?

[vanekp]

okay I found this https://github.com/hoglet67/CoPro6502
but does not say 0 = on and 1 = off bit confusing but okay.
Yes I have it set to CoPro 14 (the Null Co Pro) (CoPro OFF) and then I then use *FX151,230,3 to turn on 64Mhz CoPro in my boot file.
But it’s starting to look like I have either a faulty CoPro or it has the wrong firmware in it as I think I am correct in saying they use much the same code as in the Pi CoPro.
Will sent Jason a PM to ask him about the firmware revision.
Thanks again for your help/advice.
Peter.