I have written a little blog article on a new project, a collaboration between Ralle Palaveev and me. For those interested in the details, see here:
https://www.applefritter.com/content/a2dvi-apple-ii-digital-video-card
The short summary is: a new PICO based Apple II graphics card - just like the propular analog VGA cards - but with an alternative HDMI connector. So a card with digital video output instead of analog VGA.
It's just as simple and cheap as the original analog VGA design. And it works really well! :)
Creating this forum topic for related discussions. We're currently testing. The firmware is almost complete. Gerber files aren't published just yet, but Ralle has some PCBs for testing. If someone wants to help with testing, let us know. Otherwise be a little patient... :)
Nice!
I see you already have provisions for multiple fonts. Let me know if you're interested in supporting the font selecion protocol used by ROMX boards. Would love to see at least one more board out there that does that.
I saw the code for ROMX support in the analog VGA source base I used. It's still there but currently disabled for the A2DVI. My font selection support slightly differs from the original, due to the new "language switch" support. And I didn't fully understand what the "ROMX textbanks" were exactly meant to be doing. :D But it's certainly something that can be supported again. It's one of the topics where we could do with some help for testing...
Basically, ROMX supports a replacement Video ROM that offers up to 32 different fonts. And selection is made through the ROMX menu or programmatically using our API. If you wanted to use your existing bus sniffing to detect when a font is selected you could then activate a similar font for the DVI output. I'd be happy to help out with this as well as general testing in various machines. DM me and we can work out the details.
Amazing work, guys! Are you sure you are not using a bootstrap paradox?
Hi
I'd love to help you guys test this across multiple plato forms and configurations. Please let me know how and if I can help!!
Michael Schaffer
Thanks, yeah, not sure: I told Ralle several times, it couldn't work. But that was before finding the RP2040's two powerful slave FCUs (Flux Capacitor Units)... ;-)
@jeff, @michael: PM.
Thats great work, thanks you guys for doing this.
I'm a little hopeful with you involved Macfly, that once this is finished off, then we might see some attempt to get a A/// version working.
Hahaha, the idea has crossed my mind. :) But with the A/// it always feels there's only three people interested in related projects (me included..). But, who knows...
Here's something I have added to the A2DVI firmware: optional debug/status lines - as an option in the configuration menu. It shows the status of all Apple II soft switches at the top (in the free space above the Apple II screen), and some extra data below: currently the execution program counter, the stack pointer and address of the most recent zero-page access. It's not an exact science, since you can't see every single address, of course. Originally this was meant to help debugging the A2DVI itself.
But I find it still interesting and useful even for A2DVI unrelated cases, e.g. when your machine doesn't boot or your program was stuck, and you wonder what the heck the 6502 was doing right now. It's also interesting to see what a running program is doing - for example, executing code from a a specific slot ROM, the main ROM - or when a program enables the AUX MEM soft-switches, in order to access the extended memory banks of the IIe.
Here's an example: shows the soft-switches are configured to "HGR" (hires graphics), "40 column mode" and "page 1". All other soft-switches are off. And below: current execution PC at $AF42, stack recently accessed at $1F8, zero-page accessed at $2E...
A2DVI_DebugStatus.jpg
That's not spcific to the HDMI output, of course, could be done for analog VGA in the same way. Just shows the PICOs direct 6502 bus connection is also useful for other stuff. A card like this could be turned into a little debug/tracing utility. It has access to every single memory cycle, every single address, every single data byte. Opens up possibilities, almost like in an emulator...
I guess I'm the third one then :) I'd build it to get better color video out of my A///.
Hi,
this is awesome, also the support for another character set (I am from Austria and often use German character sets).
I want to ask if this also supports Apple IIGS or if rgb2HDMI is still the better solution for IIGS.
best regards
clockchip
This card doesn't support the Apple IIgs. (At least at this point in time, but those of us who are not involved with the project could be up for yet one more amazing surprise from Thorsten and Ralle!)
For the IIgs I would argue that the best equivalent solution is the A2FPGA card: https://wiki.reactivemicro.com/A2FPGA
Yes, IIgs support is currently not implemented. The code base from the VGA project I used did have IIgs support. But the IIgs requires additional video modes, and each mode needs to be ported for DVI separately. The IIgs modes are also a bit more tricky, due to higher resolutions, more colors and configurable palettes. Might be possible. But I don't think I'll be working on those any time soon.
Also, Raspberry announced a successor to the PICO yesterday. PICO2 has even better CPU cores and better I/O. And PICO2 is pin-compatible to the current boards. That may also allow more additions in the future...
Hi,
I am a low-income senior and would love to test the new A2DVI boards in my Apple II Plus computer.
I like playing around with basic graphics and basic math functions to sketch stuff on the screen.
e.g.,
10 GR : HCOLOR = 3
20 REM CALCULATE CENTER
30 CX = 140 : CY = 96
40 REM SET UP OCTAGON SIDES
50 FOR I = 0 TO 7
60 X1 = CX + 50 * COS((I * 45) * 3.14159 / 180)
70 Y1 = CY + 50 * SIN((I * 45) * 3.14159 / 180)
80 X2 = CX + 50 * COS(((I + 1) * 45) * 3.14159 / 180)
90 Y2 = CY + 50 * SIN(((I + 1) * 45) * 3.14159 / 180)
100 HPLOT X1, Y1 TO X2, Y2
110 NEXT I
120 END
Looks great! Are you guys done with testings and publisehd the gerber files?Very intersted in getting a few boards and building out and test.I like the 245 DIP verstion with VGA header rather than then HDMI only SMD verison althoug working with 0402 components is my happy place.
Also just to clarify, when I talked about the card not being supported on the Apple IIgs, I was referring to the 2.8 MHz native mode. When the Apple IIgs is running in 1 MHz Apple II emulation video mode, am I correct to assume that it works perfectly, just like the rest of the Pico-based VGA cards?
I don't know. :) I haven't tested any IIgs. There is a chance that the card may work, while the IIgs runs at 1MHz and is in Apple II emulation mode. If someone had tested that, it would be interesting to know.
However, even then, it wouldn't be honest to claim that the card supported the IIgs. The IIgs has a number of extra video modes - higher resolution, more colors, with color palettes etc, which make software emulation more difficult. Even more so for the DVI card, since it required a few tricks to reduce the computation overhead, which worked great for the limited number of colors required for an Apple II/IIe. There are also a few other properties of the IIgs video modes, which make me doubtful, that SW emulation (on a PICO) would lead to a "satisfactory result"...
(Btw, in my post above I incorrectly claimed that the analog VGA projects had support for IIgs video modes. That wasn't right. At least I do not see any implementation of the extra IIgs video modes in the sources of the David's or Mark's analog cards.)
We have released both - Gerber files and firmware images.
Currently Gerber files for the v1.6 board (with DIP ICs, HDMI+VGA connector) and for the v2.0 board (SMD with HDMI only) are available in Ralle's repository. See respective directories. So everyone is free to build their own boards :). We have already seen a few reports of successful builds.
Otherwise, Ralle is also offering prebuilt cards on ebay or here - with world-wide shipping... :-)
The hardware for v1.6 and v2.0 is well tested and rock solid. But we still have new ideas. You can already see a photo of a v1.7 (yet another form factor), which is not tested yet (so no Gerbers for this one yet).
The firmware is also complete and stable. At least all the standard features of an Apple II/IIe are supported. Next step will be the addition of a few extensions (like "Videx" emulation, a popular extension for the Apple II/II+).
Chris Torrence has just released a new YT video, where he compares some HDMI solutions for Apple IIs. He also shows the A2DVI card in his video and did a really good job of explaining its features:
https://www.youtube.com/watch?v=OfVwL-PrZos
Speaking of new YouTube videos: https://www.youtube.com/watch?v=rrM6bPCk8DM
Yeah, Adrian made a good job of showing some of its extended capabilities. In fact, I hadn't ported the Video7 graphics modes yet, when Adrian started looking at the card. There isn't a lot of software for Apple II using it, and before Adrian, no one ever asked about it. I wasn't aware that DazzleDraw supports one of the modes, so that was a nice find. I sent Adrian newer firmware, which added the Video7 modes, while he was filming. That's why he was surprised in the video, when the Apple Logo was suddenly showing in color - and the other modes also worked - though there were still a few minor issues at the time.
What I didn't know until the video came out is, that he was going to promote some random guy's online shop. We don't even know him and he has contributed absolutely zero to the project. He just made a redesigned clone and created a shop. And his PCB doesn't even look good or improve anything. Actually looks worse than Ralle's first prototype - with the HDMI connector even on the wrong side. That was really frustrating, when we noticed what the video was about. Especially for Ralle, who spent a lot of time designing the original board and gettings things right.
And just to mention this, if you don't want to solder your own board: Ralle also has a little online shop, where he sells assembled boards - with world wide shipping.
When I first noticed the video I also assumed that this online store is simply another affiliate of Ralle’s. Only after I watched it in full did it became clear to me that this is another maker.
I totally understand the frustration, but this is the nature of open-source. Also Adrian is not really to blame, since it would be very unethical on his part if someone handed him a card during a show, he did a video on it and then didn’t put that person’s store as the top link in the description.
Perhaps the best course of action is to contact Adrian and ask him to put the Tindie link right below the 8-bit Devices one, which is now out of stock. Tindie has a waiting list, which is very useful in situations like this. About a third of the people who get on it will make a purchase after it is back in stock. When Action Retro did a video on my card, I also ran out of stock very quickly. At one point the waiting list grew to more than 220 orders and about a third of those made a purchase once I was able to produce enough cards.
In Adrian's video, there seems to be an implicit criticism about the Maxwell's Gadgets version of the card - just from the image from Tindie being shown during the segment. While I'd love to order direct from Ralle, this was the only place an iteration of this card seems to be in stock - does anyone know the legitimacy of the impedance problem Adrian (or really, the guy Adrian got the card from) was referring to?
And yes, it was pretty clear once digging deeper during Adrian's video that the person selling the cards was not the creator, but all of this of course is indeed the nature of open source, and I think Adrian was just going on what he knew. I'd think folks would want these designs to be iterated on and available from multiple sources, otherwise why make it open source? Nothing against the great work done by Ralle et al to get this new card out, huge kudos for that, but sounds like this would be the natural progression of any new open source hardware.
I haven't tested the card you mention, but just from the looking at the PCB, you can tell the design rules for HDMI weren't followed. The outer resistors are not angled, creating unnecessary corners in the signal paths. The traces are evenly spaced, rather than keeping each differential pair close, while increasing the separation between the four pairs. So at least for the visible part, it seems signal quality wasn't considered.
The question is, does it matter for this application.
I did a lot of tests with our first prototypes, also taking advantage of a large variety of displays at my workplace (Oops, don't tell anyone! :) ). Bottom line: it's amazing with what signal quality you can get away with. The most critical displays were the really old ones. The most sensitive I have is an old 4:3 TFT from 200x with DVI input. But basically none of the modern displays ever had issues, even when it was clear that the signal had. My theory: the modern displays are all so good, because their receivers are designed for much higher bandwidth, so 640x480p is a piece of cake for them. Only for the really old TFTs the bandwidth is somewhere in the challenging area of what the display was just designed for.
Otherwise, of course it's open source - and fine to do redesigns. What I probably meant to say is, that one shouldn't just do a redesign in order to say it's somehow yours - unless you really want to change or improve something.
In the case of Chris, the gentleman in Adrian's video: we're in contact with him now and he did have good reasons why he wanted the PCB this way - and with the HDMI connector on the other side. It's also clear he is a friendly chap and just another Apple enthusiast - just like most of us. So my criticism was unfair in his case. My apologies! :)
I didn't look at the card metioned, because doing so would support Adrian and I don't think he knows what he's doing. So I'll avoid it.
As to the incorrect "rules" for hdmi singals traces, it's likely a non-inssue unless these are long traces and given the size of the boards I've seen my guess is that's not a problem because it will be resovled as soon as it gets off the card. That said, I'm curious to see the card now. Who's got a link they can share?
Are you kidding me?? And if not, can you provide an example to support what you are saying?
I don't really want to hijack this great tread, but will just say:
I don't remember exactly what he said but I've watched many of his videos and it happens several times. It's bad enough that's what I take away from his videos. Some are minor others more major and each time I think.... now 20,000 people are going to regurgitate this crap to others! Sure enough, some things I head are incorrectly conventional wisdom he's either parroting or creating. In any event, those are always bad for the group. This is also strictly from electrical/mechanical perspecitve, he's a good guy but it's clear he has no formal background in what he often talks about. I'd like for someone to set me straight on this, and I'm happy to change my opinion if anyone can.
I know you know enought to make your own judgement, and I respect that. I may watch with a more critical eye but the errors are there if you choose to notice.
I'm also not saying he knows nothing or hasn't learned some things over the years, he has some good knowledge but he also makes enough mistakes (maybe here too) that he shouldn't be treated like an all-knowing demigod.
The argument "I can't give an example, because there are too many." is straight BS and you know it. ;)
I gotta agree witt CVT. Adrian isn't perfect - nobody is - but he's an honest dude and never has put himself out there as an expert, so I don't get the issue. He regularly admits when he's wrong and corrects himself. IMHO, he's a humble friendly dude and I really enjoy his videos. Kinda a Bob Ross effect watching tbem. Saying he shouldn't be "supported" is a bit melodramatic, and you don't seem to bring forth any valid criticisms. Hes an excellent promoter of the hobby and I'm all for that.
I'm sure you can appreciate the simple fact that your request is just about impossible to respond to. It's one of those things while listening you hear something and you think, that's not right... but just move on because it's just a moment in a long video. But over you hear another, then another, and others. Then you hear folks who aren't experts in the field speaking facts they heard that aren't actually facts. The whole time the though of: "I better note the time because at some random point it the distant future someone will ask for proof of when this happened." never crossed your mind. LOL If you do this, I'll tip my hat to you becaues time travel is not something I've been able to master so any moment in time is just memory without any detal as to exactly what was said, when it was said and in what context (video) it was said.What I can say, is I'll put some of his videos on in the background and whne I catch any of those mis-truths I'll let you know.
But how do you know and more importantly how do we know that you were correct in your "that's not right" assumptions, if you cannot provide any examples?
First, I'm totally disappointed this is happening in a thread on something that is totally awesome, but since I've been questioned (challenged) I will respond.
It honestly took me one video and not long into the video either!
Video title: Repairing an Apple Disk ][ drive with multiple faults
@ 3:58 he discovers a problem with the drive rail and identifies as a grease build up, close enough something tacky. After cleaning he's got great movement and should be done, but he's not!
@4:50 - Even after realizing a problem with using a lubricant on the rails, he uses silicone lube on the drive rails. He clearly knows there are problems because he just dealt with one seconds earlier! Apple service guidance is DO NOT LUBRICATE DRIVE RAILS ... NO MATTER HOW TEMPTING IT MAY BE!!! This applies to all components in the drive, not just the drive rails, this is for a very good reason and that's because the drive was designed to not need lubrication because lubrication does bad things to disks and disk drive mechanism just as Adrian himself saw and remedied!!
No drive rail lubricant!!!.PNG
@5:20 for the Sugart mechanism... dude doesn't even know he's working on an Alps drive, ain't nothing in there that's Shugart!
@5:40 - applies berring oil to the spindle/cullet. WTF??!?!?! Really? again... this is such a bad idea! Liquids have this simple charastic when exposed to a spinning force... who remembers centripetal force? Guess where that oil spray is gonna go.... hint: everywhere is bad! Service notes cleary set the table for their service techs. Normal humans weren't supposed to be working on the drives because, in total fairness they are uneducated or worse, they're educated by some in the distant future youtube personality who has no clue what he's doing!
While Adrian does say to clean up excess so it does not drip onto the disk, that's not really good enough. Never use lubricants in a Disk II. 300 RPMs makes a nice oil vapor trail.
A little while later... Holy cow, the number of times he's talking about Shugart drives... at what point do you think he'll catch on? He notices the the schematics don't match, and board layout is different... hmmm, that's a tricky one! Nope, it's not, that is not a Shugart drive! SMH
@14 minutes into this farce, he's finally realized he's got an Alps motor controller!!! I can only wonder (really expect) does he thinks the rest of the drive is still a Shugart? LOL.
That's one video...