PiTubeDirect signalconverter for BBC Micro

[BigEd]

Just got mine - thanks Kjell! Plugged the cable the wrong way at first, but all is well now.

[sundbyk]

Just got mine - thanks Kjell! Plugged the cable the wrong way at first, but all is well now.

Good to hear.
I will make it more visible where pin 1 is.


Cheers,

Kjell S.

[BigEd]

Thanks! I see what happened now - on the level converter you have legends for the two bit connectors, P1 and P2. I'd taken those to indicate the Pin 1 (and indeed Pin 2) end of the connectors, which is exactly wrong. Fortunately, everything seems to be working.

I should have looked at the photos first.

Note that I did choose the external version of the level converter, for maximum flexibility - it's probably the only version which has this potential confusion with orientation.

(For the record, cable length does matter - daisy chaining an IDE cable with the extender cable I use for the Matchbox gave a very slightly unreliable result. An IDE cable on its own is working well.)

[sundbyk]

Thanks! I see what happened now - on the level converter you have legends for the two bit connectors, P1 and P2. I'd taken those to indicate the Pin 1 (and indeed Pin 2) end of the connectors, which is exactly wrong. Fortunately, everything seems to be working.

I should have looked at the photos first.

Note that I did choose the external version of the level converter, for maximum flexibility - it's probably the only version which has this potential confusion with orientation.

(For the record, cable length does matter - daisy chaining an IDE cable with the extender cable I use for the Matchbox gave a very slightly unreliable result. An IDE cable on its own is working well.)

Thanks,
I will send a mail to all that got this board. Counting 83 cards shipped now.

Kjell S.

[BigEd]

That's a very healthy number! Thanks for helping to give so many people second processors. I wonder if we're heading for a second peak of how many copros are in use. We just have to get to 12,000... OK, perhaps we won't manage a second peak!

[grobda]

Hi

I've PM'd you about an adaptor and PP'd a payment but the message seems to still be in my outbox, i presume this means unread.

cheers

Rick

[sundbyk]

Hi

I've PM'd you about an adaptor and PP'd a payment but the message seems to still be in my outbox, i presume this means unread.

cheers

Rick

Hi Rick,

I got the money. I am waiting for micro SD card that I ordered many weeks ago.
The first batch of card did not work on the Pi Zero. Why I do not know, they worked on Pi 3. It may have been a size problem.
I hope to have them tomorrow and will ship them the same day.

Cheers,

Kjell S.

[iainjh]

Hi Kjell,

can i buy 1 x converter to add a pi zero to a model B? I'm in Uk. My master one works beautifully, this is for a mates BBC B, to fit under the keyboard.

(duplicate request of earlier pm, apologies)


cheers! iain

[sundbyk]

Hi Kjell,

can i buy 1 x converter to add a pi zero to a model B? I'm in Uk. My master one works beautifully, this is for a mates BBC B, to fit under the keyboard.

(duplicate request of earlier pm, apologies)


cheers! iain

Hi Iain,

No problem, but I am out of SD cards. Hope to get some later this week.
If you don't need a micro SD card please send £15.50 to kjell@sundby.com via PayPal and I will ship it tomorrow.
Same address as last time?

Cheers,

Kjell S.

[iainjh]

thanks, sending funds now (no sd card for me ta, just 1 x board for a bbc b and pi zero). same address if you still have it else pls pm cheers!

[JudgeBeeb]

I am experiencing a bit of a problem with this. Here is my Pi Zero with male headers that I have soldered to it:

And here is the PiTubeDirect with the female header soldered on to it:

And here are the two connected together:

Unfortunately, this doesn't work - my Master 128 doesn't see any Co-Pro.

However, if I tilt the Pi back a little bit, like this, it does work:

So it seems that somehow there is a poor connection between the Pi and the PiTubeDirect. I am confident that it is neither the Pi Zero nor the male header (or my soldering of it) because I have exactly the same problem if I use my Pi 3 (with factory fitted header pins).
I have desoldered the female header from the PiTubeDirect and replaced it with one I bought from The Pi Hut. But I still have the same problem.

It's very annoying. Once I get it working, the very slightest of movement will make it crash and then I have to adjust it before it will boot up again.

I have got to the point where I am thinking about ditching the female header and soldering the Pi Zero directly to the PiTubeDirect. But that is not very convenient and not really what I want to do.

Does anyone have any suggestions?

[hoglet]

Does anyone have any suggestions?

Are you 100% sure it's the connection between the Pi and the level shifter?

I wonder if it's the connection between the level shifter and the Master, with the (old) sockets on the Master being tarnished.

It might be with trying to clean then by repeatedly inserting/removing a piece of header strip 10-20 times.

Dave

[BigEd]

That's a good thought. We saw people with that problem using the usual Tube connector, but it's the same risk.

[JudgeBeeb]

SOLVED.

Someone on the Raspberry Pi forum suggested splaying the pins apart on the male header so that they are a tighter fit and that seems to have solved the problem.

[BigEd]

Good to hear it!

[guidol]

Unfortunately, this doesn't work - my Master 128 doesn't see any Co-Pro.
However, if I tilt the Pi back a little bit, like this, it does work

So it seems that somehow there is a poor connection between the Pi and the PiTubeDirect. I am confident that it is neither the Pi Zero nor the male header (or my soldering of it) because I have exactly the same problem if I use my Pi 3 (with factory fitted header pins).

It's very annoying. Once I get it working, the very slightest of movement will make it crash and then I have to adjust it before it will boot up again.

I also couldnt get the Master-version to work (but the external one).
I did think it was about the bend pins from the post-service....but now I made a picture of the IDC-female from the Master-PiTubeDirect and my IDE-cable.

The female Master-IDE-Connector seems to have much bigger holes than my IDE-cable - where the pins fit tight....

Is it possible that Kjell hasnt get the right connectors? Are there male IDC/IDE connectors with bigger pins than on the Raspberry?

Take a look at the picture the gap between 2 pins is on the master-connector smaller than on the IDC/IDE-cable....

My Pi3 was on the master-connector not very tight...and also the female connector on the external converters fits not very tight - I think about to stabilize the external converter....but this one works...for now

[guidol]

SOLVED.
suggested splaying the pins apart on the male header so that they are a tighter fit and that seems to have solved the problem.

splaying in which direction....do you got a Link?

[sundbyk]

Hi,

The connector is a standard one.
But it may be a bad production from the manufacturer or damages during transport.

All cards are tested with the build in programs.

If the problem is between the converter and the master there can be a look solder point on the master.
I suggest you try to use a pencil on the pins that goes into the master.

I do this on may credit card every time is gets a bad connection.

If you still cannot find the problem I will send you a new card.

Kjell S.

[sirmorris]

Another happy customaster!

Thanks Kjell!

[JudgeBeeb]

splaying in which direction....do you got a Link?

I have splayed the two rows of pins outwards from each other. I placed a knife between the two rows and twisted it one way and then the other to place pressure on each row of pins in turn - thus causing them to bend outward. Do note that the pins are splayed only very slightly, just enough to cause them to exert just a little extra pressure within the female header. Visibly, the difference is almost imperceptible.

If you still cannot find the problem I will send you a new card.

I am very confident that the problem is not with your card. It is difficult to describe; it is much easier to see and feel it in real life. The male header pins are slightly loose in the female header socket. This means the Pi can rock backwards and forwards a little. You can see and feel it happening in the female header (and not on the surface of the PiTubeDirect board).

I think the problem is poor quality female headers. This does suggest that the header you supplied was not good. But I had the same problem when I replaced your header with one I bought from The Pi Hut. So I don't think there is anything you could have done to avoid the problem. In any event, it seems that the problem is easily solved with a slight adjustment of the pins on the male header as described above.

[sundbyk]

Another happy customaster!

IMG_3040-small.jpg

Thanks Kjell!

You welcome.


Good to see that you got the card and it works.

Kjell S.

[sundbyk]

splaying in which direction....do you got a Link?

I have splayed the two rows of pins outwards from each other. I placed a knife between the two rows and twisted it one way and then the other to place pressure on each row of pins in turn - thus causing them to bend outward. Do note that the pins are splayed only very slightly, just enough to cause them to exert just a little extra pressure within the female header. Visibly, the difference is almost imperceptible.

If you still cannot find the problem I will send you a new card.

I am very confident that the problem is not with your card. It is difficult to describe; it is much easier to see and feel it in real life. The male header pins are slightly loose in the female header socket. This means the Pi can rock backwards and forwards a little. You can see and feel it happening in the female header (and not on the surface of the PiTubeDirect board).

I think the problem is poor quality female headers. This does suggest that the header you supplied was not good. But I had the same problem when I replaced your header with one I bought from The Pi Hut. So I don't think there is anything you could have done to avoid the problem. In any event, it seems that the problem is easily solved with a slight adjustment of the pins on the male header as described above.

Just a suggestion, but it might be the male connector on the Pi that is to thin.
But it is very unlikely.

Keep me updated if anything changes..

Kjell S.

[sundbyk]

Hi all,

I have just shipped board number 103.
Very happy to see that the BBC is still can used for development.

I will keep on making and adjusting the cards as long as anyone is interested.

Will try to keep a stock, but until now they are gone before I manage to make them.

Happy Xmas everyone.

Kjell S.

[guidol]

Another happy customaster!
IMG_3040-small.jpg
Thanks Kjell!

Good to see that you got the card and it works.

Short Question: At your webpage and on his master-pcb the JP3-GNDProbe-Pins are connected... but not on my master-pcb.
Could JP3 be open?

[sundbyk]

Another happy customaster!
IMG_3040-small.jpg
Thanks Kjell!

Good to see that you got the card and it works.

Short Question: At your webpage and on his master-pcb the JP3-GNDProbe-Pins are connected... but not on my master-pcb.
Could JP3 be open?

JP3 is not a jumper at all. It is just a grounding point when you need to use a scope for development.
I have removed the text "JP3" on the external card and will remove it from the master in next batch.

Kjell S.

[JudgeBeeb]

Just a suggestion, but it might be the male connector on the Pi that is to thin.

Obviously, it must either be the male header or the female header (or both). The frustrating thing is that ultimately I ended up using both the male header and the female header that came with my Pi Zero starter kit from The Pi Hut. You would hope that one way or another these two would work well together. But the problem was still present.

[bsdnazz]

I'm trying to book a Pi 3 with an SD card from sundby.com but I'm not sure it's working.

When powering on using the sundby.com SD card the red LED on the Pi comes on, the green flashes once and then the red LED stays on. Is this expected?

I have a different SD card that seems to Linux boot fine.

[guidol]

When powering on using the sundby.com SD card the red LED on the Pi comes on, the green flashes once and then the red LED stays on. Is this expected?

Thats normally on the P3, because the Kernel is under 1MB in size. The Kernel will be loaded (short flash on the green "Drive"-LED) and the
rest will be done in CPU/Memory, so only the red Power-LED will stay on.

If you got a 3.3V TTL serial Adapter then you can see the Pi booting in 1-2 Seconds

Only a Pi A+ (like a Zero) here the green LED did stay on on every second BREAK from the BBC.

[bsdnazz]

Thanks. Time to get a serial lead to attach to the PiTubeDirect.

[BigEd]

I think, on the Zero at least, the LED is toggled for each Tube access, as a kind of activity light:
https://github.com/hoglet67/PiTubeDirec ... ula.c#L479