Andres' H5 B1 Build

[exxos]

Do you think that the lack of the independent 16 MHz oscillator may have an impact? Because, as I mentioned before, I don't have it installed (but SJ3 is bridged).

It wouldn't really matter what any inputs are doing if the outputs are all lifted.

[AndresPlazaR]

@exxos, I'm trying to trace all the related connections about this problem, but I cannot find one: pin 2 of JP17 (Drive AB Swap).

In the schematics for H5A (could not find one for H5B1), it is labeled "U32IP". It seems to me that is should be "DRIVE0", but it is not connected there. Although strange, I also tested the "IP" connections (because of the label), and also nothing. Then I tested every pin in the GAL, the Yamaha, the WD1772 and the floppy port; nothing.

Any idea?

[exxos]

In the schematics for H5A (could not find one for H5B1), it is labeled "U32IP". It seems to me that is should be "DRIVE0", but it is not connected there. Although strange, I also tested the "IP" connections (because of the label), and also nothing. Then I tested every pin in the GAL, the Yamaha, the WD1772 and the floppy port; nothing.

It is buffered thats why...

1.PNG

2.PNG

Also 1772 signals may show more when your trying to access the floppy... so you may have to keep pressing "retry" to keep the signals all looping.

[AndresPlazaR]

So, I will need to bring all my computers to storage for a few months, because we are moving to a new (larger!) place (bigger lab!), so it will take me a while to keep searching what's the problem.

[AndresPlazaR]

Hello!

So, I wanted to give an update about this, for posterity. :D

After 2 years, I finally started to look at my projects again, and a couple of days ago it was the turn of my H5 B1 build. It was great to have these posts, because I was able to read them again and remember what I have tried, the help and suggestions received, and not have to start all over again.

Just by chance, trying something, I disconnected the cable between the CF card connector and the Trudie... and the floppy/Gotek worked. I tried the cable+connector, without a CF card, and that also worked. I tried different CF cards, but in that situation the Gotek will always failed/was not detected. I know the CF cards are fine, and I don't have a spare CF connector and cable, so I was looking at it closely... and a connection between the connector itself and the little board were bend, touching the connector right next to it. I fixed that and, what you know, the Gotek worked without any problem!

So, to recap: this is a H5 B1 board running TOS 2.06, with a Trudie v5.2 (the 5v one), pull up fix board, Winamp board and Gotek drive. GAL is installed, but not the 16MHz oscillator, so SJ3 is jumped. JP18 is open (force drive 0 to 1.44); JP22 is 1-2 (8MHz & 16MHz GAL mode). Everything works, including when I switch to TOS 1.04.

But still don't understand why, if that connection in the CF connector was the culprit, the Gotek did work with TOS 1.04. Not sure the relation between those two, but I image it will remain a mistery.

Thanks again to @exxos, @Icky, @kodak80 and others for all the help!

Now, I will try the X2 MIDI synth.

Andres.

[exxos]

:bravo:

Would be interesting if you can state which pins were bent / shorted on the ide connector.

I would assume it was a databus short. IIRC TOS 206 looks for IDE devices, TOS104 does not. So likely TOS206 saw the IDE interface and tried to execute the boot sector. Which it can't, so it bombs.

[AndresPlazaR]

:bravo:

Would be interesting if you can state which pins were bent / shorted on the ide connector.

I would assume it was a databus short. IIRC TOS 206 looks for IDE devices, TOS104 does not. So likely TOS206 saw the IDE interface and tried to execute the boot sector. Which it can't, so it bombs.

Thanks!

If I'm counting correctly, pin 17 (A03) was bend, touching pin 42 (WAIT).

Andres.

[AndresPlazaR]

@exxos : per your recommendation here (viewtopic.php?f=89&t=3602), I'm trying to remove the winamp card (installed more than 2 years ago). The cable that goes to the terminal OP of the little board is connected to the audio gen circuit, and it seems that I removed a capacitor there, but I cannot find documentation on what was the original value (so I can install it back). Looking at the schematics, I think it is C8 (1uF), but I'm not 100% sure (there are no labels right in that position. Do you remember? Do you have specs on the size, too?

Thanks,

Andres.

[exxos]

I think it is C8 (1uF), but I'm not 100% sure (there are no labels right in that position. Do you remember? Do you have specs on the size, too?

Probably correct. You would have to take a image of your board so I can see what's missing.

[AndresPlazaR]

Probably correct. You would have to take a image of your board so I can see what's missing.

Yes, of course. This morning I woke up thinking I should have done that. :-)

Here it is:

PXL_20230409_143003741.jpg

Thanks,

Andres.