exxos's Atari, Amiga & retro forum

Icky wrote: 26 Jun 2024 10:28 But mostly I need to get back on top of things to start the ball rolling again.

No problem, we'll wait. Get well. And the sooner the better :)

Created a SHIFTER Test board to test the FPGA is functioning correctly on the Phoenix Shifter. Similar to one for the MMU and BLUE boards - https://www.exxosforum.co.uk/forum/view ... 10#p134258

Its been long time coming and it had its preview at Cyber Legends 5 - Here is the Phoenix Shifter v5 TANG Edition





Well things have turned around a bit. I started looking at what was wrong with several things about the Phoenix Shifter. Firstly I couldn't understand why the shifter only worked on some monitors / TVs this turned out to be we were driving everything from the 32MHz line and attempting to provide a crude resolution out to the HDMI port. Also Closure was still having issues running for various reasons.

So I started to think how do we go about fixing the Phoenix Shifter to not be constrained to the 32MHz but be able to always represent the ST screen at a resolution of say 720p as most monitors / tv's support this. Then there is no need for figuring out if a TV or monitor will work for the Phoenix Shifter.

So my plan was provide the native screen then use a frame buffer and let that using circuitry like the ADV7513 create the 720p output from its clock. I started to redesign the Phoenix Shifter as v5.0 and things started to get away from me as I figured out more and more how I could create a better product. I ended up with all these features I wanted to do and so many questions on whether it would work. There would be a lot riding on the new board in terms of costs and unknowns. Because of this I ended up going down two routes.

1. Continue to see what could be fixed on the v2 Phoenix Shifter to close out the original Shifter Core and make sure it was adhering to the original
2. Design out the v5 using the Max10 but because of costs I ended up looking at a TANG 20K board that I already had.

Well both of these routes paid off I managed to get the shifter v2 to play nicely with Closure and in using the TANG I thought it was just a stop gap towards the MAX10 v5 as a proof of concept. Well the TANG version turned out to be a lot more.

1. Be the same footprint as the original shifter chip (well it is as near as it can be) - so can be used on any ST :)
2. Provide a 720p @ 60Hz output over HDMI
3. Switching to Mono display or Medium etc without any TOS patching
4. Video Effects and sizing
5. Provide a codec to mix the Sts YM sound and a MIDI board like the S2 together and out through the HDMI
6. User firmware upgradeable from the SD card in the TANG, has fall back golden source which replaces any firmware if it bricks
7. A Phoenix Eco System Panel to control the Shifter including firmware upgrade and other Phoenix board functions.
8. Splash screen on boot and info overlay - can be turned off

TANG 20K onto of the PhoenixShifter v5.0 TANG Edition board - plug straight into the Shifter socket


TANG 20K onto of the PhoenixShifter v5.0 TANG Edition board underside


Phoenix Panel showing Phoenix E-Boards installed


Firmware Update Demo





I will post some more info on this soon including Closure run.

Very nice

cool

Icky wrote: 21 Oct 2026 20:59

btw, I see that pixels are stretched differently, e.g. letter "i" in "File" vs "View". Is it a grabber issue, or something else?

Cyprian wrote: 21 Oct 2026 21:29 btw, I see that pixels are stretched differently, e.g. letter "i" in "File" vs "View". Is it a grabber issue, or something else?

Yeah it’s the scaler option I am using there are several options that scale in different ways.

Of course a Med Res is 640x200 and scaling to 720p there are many ways you can do that. For example the Integer option is 1:1 so smaller on the screen but a pixel to pixel mapping. I'll do a write up and show all the options.

Even while only understanding half of this and loosely following the FPGA and Phoenix work this seems like a thing of beauty.

Icky wrote: 21 Oct 2026 21:37

Cyprian wrote: 21 Oct 2026 21:29 btw, I see that pixels are stretched differently, e.g. letter "i" in "File" vs "View". Is it a grabber issue, or something else?

Yeah it’s the scaler option I am using there are several options that scale in different ways.

Of course a Med Res is 640x200 and scaling to 720p there are many ways you can do that. For example the Integer option is 1:1 so smaller on the screen but a pixel to pixel mapping. I'll do a write up and show all the options.

it sounds great