Project: HDMI/DVI out for STFM

Progress on our FPGA cores.
User avatar
exxos
Site Admin
Site Admin
Posts: 23488
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: Project: HDMI/DVI out for STFM

Post by exxos »

Icky wrote: Tue Jan 01, 2019 2:12 am I have a working STFM arriving in the next few days so will try the board out on that one too. If I am still having issues I will send my DVI board to exxos to check on his STFM to see if it is working there.
:thumbup:

I forgot (Again sorry) what you was using before, think it was the "ST" and STF remake ? So STFM would be good as its what I tried it out on.
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
User avatar
Icky
Site Admin
Site Admin
Posts: 3986
Joined: Sun Sep 03, 2017 10:57 am
Location: UK

Re: Project: HDMI/DVI out for STFM

Post by Icky »

exxos wrote: Tue Jan 01, 2019 1:37 pm
Icky wrote: Tue Jan 01, 2019 2:12 am I have a working STFM arriving in the next few days so will try the board out on that one too. If I am still having issues I will send my DVI board to exxos to check on his STFM to see if it is working there.
:thumbup:

I forgot (Again sorry) what you was using before, think it was the "ST" and STF remake ? So STFM would be good as its what I tried it out on.
Problem exists on 520ST and STF Remake so as you say trying on an STFM would be good.
User avatar
Icky
Site Admin
Site Admin
Posts: 3986
Joined: Sun Sep 03, 2017 10:57 am
Location: UK

Re: Project: HDMI/DVI out for STFM

Post by Icky »

Icky wrote: Tue Jan 01, 2019 1:55 pm
exxos wrote: Tue Jan 01, 2019 1:37 pm

:thumbup:

I forgot (Again sorry) what you was using before, think it was the "ST" and STF remake ? So STFM would be good as its what I tried it out on.
Problem exists on 520ST and STF Remake so as you say trying on an STFM would be good.
The plot thickens - Finally got the new (well new for me) STFM and it was functioning correctly.

Fortunately the shifter was already socketed which saved some time. I popped in the HDMI / DVI board and booted.

It did not reset. Have had it running GEMBench for over 30 minutes and still has not reset.

Just to check I put it back in the 520 ST and it starts resetting again.

One thing though is that I am getting a shimmering on the display on the STFM - will look into that next as well.

IMG_3488.jpg
IMG_3488.jpg (126.02 KiB) Viewed 4174 times
User avatar
exxos
Site Admin
Site Admin
Posts: 23488
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: Project: HDMI/DVI out for STFM

Post by exxos »

Icky wrote: Fri Jan 04, 2019 5:44 pm One thing though is that I am getting a shimmering on the display on the STFM - will look into that next as well.
Thats the issue I had...


https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
User avatar
Icky
Site Admin
Site Admin
Posts: 3986
Joined: Sun Sep 03, 2017 10:57 am
Location: UK

Re: Project: HDMI/DVI out for STFM

Post by Icky »

exxos wrote: Fri Jan 04, 2019 5:46 pm
Icky wrote: Fri Jan 04, 2019 5:44 pm One thing though is that I am getting a shimmering on the display on the STFM - will look into that next as well.
Thats the issue I had...
At least we are consistent :)

So interestingly from my testing I see the following traits

ST ModelRevisionResettingShimmeringComments
520 STMC070243 REV. EYesNoRock solid display can be seen if you can get it past resetting and playing a game
520 STFMC070789-001 REV. CNoYesShimmering even present playing a game
STF RemakeC070789-001 REV. FYesNoRevision is from the donor STFM that gave the remake most of its parts. Seems to exhibit same behaviour as 520ST
User avatar
exxos
Site Admin
Site Admin
Posts: 23488
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: Project: HDMI/DVI out for STFM

Post by exxos »

Icky wrote: Fri Jan 04, 2019 6:07 pm At least we are consistent :)

So interestingly from my testing I see the following traits
Very odd..

Add this cap and I bet you be working fine...


https://www.exxosforum.co.uk/forum/viewt ... 270#p14777
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
User avatar
Smonson
Posts: 708
Joined: Sat Oct 28, 2017 10:21 am
Location: Canberra, Australia
Contact:

Re: Project: HDMI/DVI out for STFM

Post by Smonson »

Thanks for finding this out Icky! Amazing work!
User avatar
Icky
Site Admin
Site Admin
Posts: 3986
Joined: Sun Sep 03, 2017 10:57 am
Location: UK

Re: Project: HDMI/DVI out for STFM

Post by Icky »

exxos wrote: Fri Jan 04, 2019 9:38 pm
Icky wrote: Fri Jan 04, 2019 6:07 pm At least we are consistent :)

So interestingly from my testing I see the following traits
Very odd..

Add this cap and I bet you be working fine...


https://www.exxosforum.co.uk/forum/viewt ... 270#p14777
Out of interest what value did you use?
User avatar
Icky
Site Admin
Site Admin
Posts: 3986
Joined: Sun Sep 03, 2017 10:57 am
Location: UK

Re: Project: HDMI/DVI out for STFM

Post by Icky »

Icky wrote: Sat Jan 05, 2019 6:46 pm
exxos wrote: Fri Jan 04, 2019 9:38 pm

Very odd..

Add this cap and I bet you be working fine...


https://www.exxosforum.co.uk/forum/viewt ... 270#p14777
Out of interest what value did you use?
10nF actually made the board not work - black screen.

47pF works fine.

Screen is now stable on STFM.

EDIT: Just tried the HDMI board back in the STF Remake and 520ST with the 47pF cap in place and its even more temperamental. Some times its just a blank screen like when I used the 10nF when in the STFM and not very often it might try to boot and of course reset. On reset it mostly goes back to blank. I guess the 16MHz line is not so happy in these two machines with the cap on it.
User avatar
exxos
Site Admin
Site Admin
Posts: 23488
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: Project: HDMI/DVI out for STFM

Post by exxos »

Icky wrote: Sat Jan 05, 2019 8:06 pm 10nF actually made the board not work - black screen.

47pF works fine.

Screen is now stable on STFM.

EDIT: Just tried the HDMI board back in the STF Remake and 520ST with the 47pF cap in place and its even more temperamental. Some times its just a blank screen like when I used the 10nF when in the STFM and not very often it might try to boot and of course reset. On reset it mostly goes back to blank. I guess the 16MHz line is not so happy in these two machines with the cap on it.
Anything over about 390pF will squash the signal to much. Its not a good fix, but I still suspect its a clocking issue.
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Post Reply

Return to “FPGA DEVELOPMENT”