Project: HDMI/DVI out for STFM

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rubber_jonnie
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Re: Project: HDMI/DVI out for STFM

Post by rubber_jonnie » Tue Mar 19, 2019 9:03 am

exxos wrote:
Tue Mar 19, 2019 8:37 am
I was going to suggest trying the remake board :lol:
Can't do that until I finish the board :(

In the meantime I will try some other STFMs, provided I can find one or two with the Shifter that is socketed.

I'll also try with the vsync connected. Which pin of the Glue does this need to be connected to?
Collector of old Atari things:
800XL + Ape Warp mod, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg) + Gotek, 1040STFM + Vortex ATOnce + Gotek, 1040STF long button floppy, 4160 STE with Gotek and ROM switcher, 4160STE with 32Mhz booster, ROM switcher and CosmosEx, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

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Smonson
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Re: Project: HDMI/DVI out for STFM

Post by Smonson » Tue Mar 19, 2019 10:48 am

Great video - thanks for going to the trouble to post it. Those vertical bars are definitely not data line issues - that's the so-called "every other 16 pixels background" problem which manifests as a blank bar of 16 pixels every 80 pixels in mono. It's purely to do with the timing of when data is loaded into the shifter, compared with the shifter's internal counter. And it probably means the shifter misread one of the signals lines for a moment: load, rw, cs, or de.
exxos wrote:
Tue Mar 19, 2019 8:37 am
With the bliter enabled, the extra load on the bus could be causing it to trip up and the shifter issues are the outcome...
Agreed! By the way, I didn't necessarily mean a problem with your power supply, but maybe the power supply just to the mod board - it draws a lot of current through just one pin each of the shifter socket, 5v and GND, which is generally not a great idea electrically, but very convenient... Do you have a machined-pin IC socket for your shifter, or the normal cheaper type?

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Re: Project: HDMI/DVI out for STFM

Post by exxos » Tue Mar 19, 2019 11:25 am

Smonson wrote:
Tue Mar 19, 2019 10:48 am
Agreed! By the way, I didn't necessarily mean a problem with your power supply, but maybe the power supply just to the mod board - it draws a lot of current through just one pin each of the shifter socket, 5v and GND, which is generally not a great idea electrically, but very convenient... Do you have a machined-pin IC socket for your shifter, or the normal cheaper type?
All my sockets 40 pins are the "cheaper" type. Though to be fair, I have had a lot less trouble with those than the turned pin ones.

If its a possible "miss-read" on a line, if RJ places his scope on x1 on each shifter pin one by one, normally its enough to solve such issues, assuming its a noise related issue, which 99% of the time things are.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

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Re: Project: HDMI/DVI out for STFM

Post by Smonson » Tue Mar 19, 2019 11:32 am

That's fancy, I just use my fingers :lol:

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Re: Project: HDMI/DVI out for STFM

Post by exxos » Tue Mar 19, 2019 11:36 am

Smonson wrote:
Tue Mar 19, 2019 11:32 am
That's fancy, I just use my fingers :lol:
Yeah me to firstly :lol:
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

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Re: Project: HDMI/DVI out for STFM

Post by rubber_jonnie » Tue Mar 19, 2019 12:11 pm

I'm a visual person, so the video was the best way for me to show you all what I meant.

As for the socket, it is not turned pin, but a cheap one which was already fitted to the board when I got it, and I don't think I have a machined one spare. In fact I think my machines that do have a socketed shifter are all the cheap type socket. It's just the way they came.

In terms of putting a scope on it, that is feasible and would be a good test of my USB scope, though I would need some guidance as to what I'm looking for and a procedure to follow.

Would it be feasible to power the mod board using the floppy power connector? At least just for testing purposes, as the machine at present is a bare board with no floppy.
Collector of old Atari things:
800XL + Ape Warp mod, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg) + Gotek, 1040STFM + Vortex ATOnce + Gotek, 1040STF long button floppy, 4160 STE with Gotek and ROM switcher, 4160STE with 32Mhz booster, ROM switcher and CosmosEx, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

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Re: Project: HDMI/DVI out for STFM

Post by exxos » Tue Mar 19, 2019 12:47 pm

The scope is just to load pins.. You could (and probably better) use a small pF cap, something like 47pF on a fly lead with one end soldered to 0V. Then just go over each pin on the shifter one by one, and see if the video improves (becomes more stable when the 47pF is on any particular pin).

The scope does the same, but is only normally around 5-10pF.. Usually that's enough but sometimes its not.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

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Re: Project: HDMI/DVI out for STFM

Post by rubber_jonnie » Tue Mar 19, 2019 1:04 pm

exxos wrote:
Tue Mar 19, 2019 12:47 pm
The scope is just to load pins.. You could (and probably better) use a small pF cap, something like 47pF on a fly lead with one end soldered to 0V. Then just go over each pin on the shifter one by one, and see if the video improves (becomes more stable when the 47pF is on any particular pin).

The scope does the same, but is only normally around 5-10pF.. Usually that's enough but sometimes its not.
Roger that!
Collector of old Atari things:
800XL + Ape Warp mod, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg) + Gotek, 1040STFM + Vortex ATOnce + Gotek, 1040STF long button floppy, 4160 STE with Gotek and ROM switcher, 4160STE with 32Mhz booster, ROM switcher and CosmosEx, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

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Re: Project: HDMI/DVI out for STFM

Post by Icky » Tue Mar 19, 2019 9:40 pm

Just to confirm have tried the same on the ST Remake as this is the only one I have a blitter in.

Without vsync and blitter enabled I can not reproduce your behaviour RJ. The boards are working ok.

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Re: Project: HDMI/DVI out for STFM

Post by rubber_jonnie » Wed Mar 20, 2019 10:17 am

Icky wrote:
Tue Mar 19, 2019 9:40 pm
Just to confirm have tried the same on the ST Remake as this is the only one I have a blitter in.

Without vsync and blitter enabled I can not reproduce your behaviour RJ. The boards are working ok.
All the more reason for me to try some other boards I think.
Collector of old Atari things:
800XL + Ape Warp mod, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg) + Gotek, 1040STFM + Vortex ATOnce + Gotek, 1040STF long button floppy, 4160 STE with Gotek and ROM switcher, 4160STE with 32Mhz booster, ROM switcher and CosmosEx, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

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