Anonymous
User login
Please support the defense of Ukraine.
Direct or via Unclutter App
Active forum topics
Recent content
Navigation
No Ads.
No Trackers.
No Social Media.
All Content Locally Hosted.
Built on Free Software.
We have complied with zero government requests for information.
@CVT you were not kidding. It looks great. I always use scanline emulation with my upscale converters, so this feature in software is fantastic to not need an expensive device like my XRGB2.
20231001_191058.jpg
20231001_190934.jpg
That VGA -> HDMI adapter looks pretty nice and the price is certainly attractive. In today's world HDMI is generally more useful than a DB15 VGA connector anyway. Although I have a few really old monitors which only do DB15 but they're old enough who knows how long they will still be working. I have a few others that have both DB15 and HDMI but again, mostly older ones. Most of the newer stuff only has HDMI or maybe Display Port.
I hear you there. Thankfully the last two monitors I bought in recent years still had VGA D-Sub inputs along with the HDMI. Otherwise for my displays lacking VGA, I am a big fan of Extron devices like their RGB->HDMI, but they can be quite costly.
I have 2 terminals for my RC2014, one is a VGA and one is HDMI. I actually default to the HDMI one, but making them requires a Pi 3 B or something, and they are not nearly as cost efficient as the pico style VGA cards, i.e. https://rc2014.co.uk/modules/pi-pico-vga-terminal/I tried this VGA card with the Brain Board for fun. I should figure out the soft dips in the readme for forced monochrome mode, but otherwise, it works :) Of course the laser 128 has no cassette input so that's pretty limiting, but the combo should work fine in a IIe as well.
20231002_120843.jpg
Scanlines on but no soft monochrome enabled:
20231002_121108.jpg
My PCBs showed up today. After work I spent about an hour assembling one. Programmed it with with the 1.0 IIe firmware from the original github project, popped it in, and.... nothing but inverted @ symbols on the VGA display. The IIe is is booting normally. If I plug in my composite monitor, I get the expected image on there. But just get @'s on the VGA. Same results in slot 3 and 7 (I'm assuming this could be used in 3, given there is no ROM). Looked at the board under a magnifying glass. I don't see any obvious bad/missed joints. So I'm not sure whats going on with mine. Obviously at least the VGA signal portion is working.
A picture of your card?
A2 VGA Front.JPG
A2 VGA Back.JPG
With the card on slot 7 of an Apple IIe, I get inverted @ if I remove either only U2 or only U3. Removing U1 however produces this screen with the lower half flashing:
Without U1.JPG
My guess is that one or more of your 74LVC245 is bad. Try to get this screen yourself without U1 and by testing all three 74LVC245 in the U2 and U3 sockets.
Hmm. Brand new from Digikey. But I guess anything is possible. I do have a backbit chip tester pro. It can test 74ls and 74hc chips. But I'm not sure if either of those test modes would work with a 74lvc.
Edit: with U1 out, I still get inverted @s. I juggled around some of the ICs, but everything I tried so far just gives me @s.
Edit 2: someone else just told me the LS mode of the tester should at least provide a sanity test at 5v, but may not catch issues present at 3.3. All 3 ICs passed the 74ls245 test.
I built one on the new PCBs so I know they are good. My gut would also be the DIP ICs, the regulator and pi are likely OK.
Btw, this card will also work with 74HCT245 chips if you happen to have some. It is not recommended to use it for long periods as they will put a bit more load on the Apple II bus chips, but just for a short test it's not a problem.
Im sure its something on my end. The odds of a bad PCB are extremely low. I already posted front and back photos 2 or 3 posts up. Or what photo are you looking for?
odd, the post when I replied looked like you were asking for a photo, but once I replied it didn't.
Sorry, I didn't refresh my tab to see you posted photos while I drafted that post.
I forgot to ask: is every single character on the VGA display an inverted @ symbol, or are there 3 or 4 that are not? This card shows every single one being inverted @ only if you remove all three 74LVC256 chips or power it through the Pico using a USB cable outside of the Apple II. Otherwise when you have it inside the Apple IIe with at least on chip in its socket, a few characters are not the inverted @.
Every single character. This IIe (enhanced) is loaded (2 SSC, Phasor clone, Mouse card, Yellowstone), so I removed each card 1 by 1 to see if it made a difference. Every power up was the same. Even pulled the 80 col/64k card out of aux after removing all other cards, no change. I do have a platinum IIe in the basement I could try the card in. Or I could build a 2nd card and see what happens. Unless anyone has any other ideas.
All at signs.jpg
I found the problem: R6, R7, R8, R9, R10 and R11 are 100K on your card. They should all be 1K.
Look at the color bands on those resistors on my card:
AppleIIVGA.JPG
Last night I pulled the ICs and checked the sockets. I didn't do a deep dive. Just a sanity check. Most of the pins in the top row of the socket have continuity to the same pin in the top row of the other sockets. And most in the top row had continuity to a pin in the bottom row of the pico. Most of the bottom pins in the socket each had continuity to a trace on the edge connector.
I just pulled all the ICs and did a voltage test on U1 and 2. I checked from pin 20 to the heat sink/ground on top of the regulator that I'm seeing 3.26-3.3vdc. I couldn't easily get my probe on u3's socket for pin 20 or pin 10 for ground on any socket while in the case. But outside the case I can see continuity from all 3 sockets pin 20 to each other. And all 3 sockets have continuity from pin 10 to the regulator heat sink. So all the sockets should have power.
I tried the platinum IIe, same issue.
Looking at @CVT's post, I think he's right about a reisitor mistake at those locations being the issue.
Son of a... Yup. Digikey put 100k resistors in a 1k bag. The worst part is, I didn't even have 100k resistors in this order. The only resistors in this order were specifically for this card. And I didn't even think of double checking. Just grabbed them out of the bag and installed them. Ugh. And i don't think I have any small 1k's on hand. Most of my stock of supplies is for working on tube radios where I'm using much larger 1w+ resistors. Guess I'll add it to the list for my next parts order. And this time, I'll double check them when they arrive.
I knew it had to be something on my end. Thanks a lot guys!
DK 1k resistor.JPG
Ouch! At least we found it, but a mislabelled bag really hurts. Glad you didn't build a whole 2nd card already.
I usually clip one of these onto a couple of parts in any new batch, it has saved me a lot of headaches with way out of spec but 'new' capacitors and resistors.
Multi-function component tester (amazon)
Luckily I have a Hakko desoldering gun. So this card should be easily salvageable once I get the proper resistors. I actually do have that same tester. I mostly just use it if I suspect something is bad. But maybe I need to get in the habit of double checking all parts when they come in. I just tend to get overly excited when starting a project like this, and jump right in.
Off topic: I wouldn't recommend getting any chinese stuff from Amazon, since all they do is jack up the price by a factor of 2 and sometimes 3.
I got the TC2 from AliExpress, which has a bigger screen with more pixels for less than half the price:
https://www.aliexpress.com/item/1005002488012717.html
Duly noted! Appreciate the link, that is a much better deal.
I got the cards that skate sent today. Very nice! Much thanks for him in setting this up. I already ordered the parts I didn't already have on hand so I am expecting that by some time next week I will have boards ready to test.
I just tested soft monochrome mode, it also looks really good.
As CVT noted for scanlines in slot 7, POKE 49392,1 enables them
For soft monochrome per the docs, run
POKE 49185, 128For changing the color of text/foreground (slot 7 still), once soft monocrhome is on, increment the register to 49393 (up one from scanline setting). The commands for white, green, or amber text in that order, are a value of 1, 2, or 3 set with POKE 49393,# .Amber looks amazing. I actually think I like it better than green; amber are definitely the earliest computer monitors I remember having in the house growing up.
Amazing how much better it works when Digikey puts the proper resistors in the bag. And you can bet they were checked with a meter this time! The color is off in the picture, but looks correct in person (the orange is well, orange and not red and the vilot is lighter). And this monitor lacks any kind of aspect correction (infact I think its an odd aspect to begin with, not even 16:9). I don't know how much it matters, but I noticed the original schematic called for 1% resistors for the RGB lines. As long as I had to re-order the 1k's, I also got the 510's and 2k's in 1% and replaced those too. Not sure how much of a difference it really makes.
As there is no ROM, it works great in slot 3. So I can use a normally empty slot. Just need to figure out how to route the connector. My IIe is cramped, so I can't really use any of the small connectors on the back without blocking a slot in use. I wonder if it would be possible to 3D print an adapter bracket to fit the large hole above the PSU, and run a short VGA extension to that..
Big thanks to skate323k137 for handling the logistics of ordering and selling the cards and to CVT for pointing out Digikey's (and technically my) mistake.
A2 VGA.jpg
I was looking at the directions for programming the Pico... It says to plug it into a "Windows" machine with the BOOTSEL button held down and then you drag the firmware file into the drive...
I am assuming that this will work the same if I do it with MacOS or Linux? Because I don't have access to a Windows box (or any interest in that really).
Yes, I use current MacOS no problem. Once you drop the file, the drive ejects itself and MacOS harmlessly complains, and you're good to go.
Thanks... that was what I was assuming, but I thought I'd ask just to make sure.
Btw, this approach of programming the Pico firmware with a compiled binary is super easy and convenient, but it leaves the machine exposed to a USB Rubber Ducky attack, so it's wise to perform it on a sandboxed machine.
More on this attack here: https://www.ijert.org/metasploit-payload-injection-by-using-raspberry-pico-pi
It's not clear from that article whether this is just because of auto execute flaws inherent in Windows and whether other platforms like Linux or MacOS would be affected. Obviously the example they showed in that article wouldn't work since it uses a Windows .exe which won't run on a Linux or MacOS machine anyway, at least not without some kind of emulation.
Anyway, one would hope that a newly aquired Pico and binary downloaded from a trusted source like these GitHub repositories controlled by people known in the Apple II community wouldn't contain malicious code to begin with. Other stuff randomly downloaded from who knows where of course should be viewed with caution.
Anyway, I did a little googling on this and it is probably not at all an issue if you are using the firrmware for this card. It would take someone adding a bunch of malicious code to it on the repository, and that'd probably get noticed. Also it appears that since the rubber ducky is just emulating a keyboard and sending a bunch of commands it makes a difference what account is logged in (often a problem on Windows because so many people use accounts with too much permissions like administrator), and the malicious code is as I suspected, platform specific so Windows exploits probably won't do anything at all on Linux or MacOS. The attacker would either need to know what platform they were attacking or really go out of their way to write code flexible enough to determine the host OS and run the right set of attacks. On Linux or MacOS, without the root password it's more limited what those attacks can do.
Well, hackers very rarely write code. They simply use code that is already available. Determining the OS is not a problem, once the Pico is inside the USB. Even the factory firmware already does that, which is why you can use this approach in various platforms. There are many ways to get people to install a firmware that turns it into a Rubber Ducky. One approach is to create a branch of the original, that provides some valuable improvement. Another is to provide a binary where the scanline emulation is on by default and post it here. Once a Rubber Ducky, it will work in any OS and it can wait for a terminal with root access and then type and execute any command really fast.
The point is this: from a security perspective dropping a binary file into a Pico is equivalent to at least executing that binary on the machine the Pico is connected to and at most executing that binary with root privileges.
If you plug in a Pi and a bunch of HID keyboards show up, it's pretty obvious. Don't run stuff as administrator/root especially login sessions. I have little concern flashing new Picos from MacOS as a normal user. Admin on windows, maybe some caution there is in order of course. And I'm sure plenty of us have spare computers with USB doing literally nothing if we are paranoid.
Well, don't plug unknown USB devices into your computer... Presumably if you buy your RPi Pico from a reputable vendor like DigiKey, you're probably safe there. Buy from some fly by night Chinese vendor on AliExpress or eBay or wherever... maybe not so much.
And don't download code, especially binary code from unknown sources unless you kow what you are doing. As I said, Github accounts of known community members are probably reasonably safe. It seems a little paranoid to be worried about someone targeting such a tiny audience as people building Apple II VGA cards and creating a forked repository with new and useful features. I don't know very many people who would be capable and even aware of this project other than you and I really I don't think you are the kind of person who would try to h4x0r the people on Applefritter so I'm really not all that worried. Maybe for something that would get a lot more attention than this it might be a different story. I guess in those cases doing it on an air-gapped laptop or a VM might be a valid concern.
And I guess a third thing probably is not to leave USB devices plugged in any more than is needed.
The rubber ducky attacks are most often carried out against machines which the public has access to, or by sending someone an infected device and hoping they plug it in. It is less likely to affect someone's home computer as long as they follow the above advice I would guess.
I've seen some computers in public places where the USB ports are covered or in some cases I've even seen them filled with epoxy to keep people from plugging unknown devices in. Under Linux it is possible in software to disable USB ports which might be a good idea to do on machines which might be susceptible. It's less drastic than permanently disabling them with epoxy.
I was at DEFCON a few years ago talking to a couple guys who had given a talk about using Windows security policies to lock down desktop machines. I showed them a bunch of exploits that could do things like open up an IE window at get Internet access on supposedly locked down machines. They had to come up with a few new ways to lock those things down too. I'm as I've said not even a Windows guy, and really have only used it as little as I could get away with in work settings, but I was still able to find holes. This was back in the XP/Vista days so I imagine a lot of those things were fixed a long time ago. But probably a few new things added. Thankfully I haven't had to deal with Windows at all in several years. The less I do, generally the happier I am.
I suppose at some point they're going to have to add some kind of nag to USB device connection, informing the user a device is trying to be connected, what it is, and maybe even having the host machine scan the device for suspicious things. If you plug in something that is supposed to be a USB flash drive and it comes up saying it is a keyboard that might be a clue. If you're suspicious on Linux you could look at the dmesg or run usb-devices or some other utility like usbview to see what is configured. I would assume there are similar utilities for Windows and MacOS.
Yes, as I mentioned earlier I was planning to compile the binaries with the scanlines emulation turned on by default and post them here, so it seemed like the perfect example to make my point. :)
I didn’t bring it up for people to be paranoid, but rather to be aware. Most people are already aware of the risks involved in running a binary downloaded from the Internet, but they are not aware that it’s the same risk when you drop a binary into a Pico. After all it's just a UF2 extension - what could it possibly do?
Also the low popularity of this particular project is not relevant, since Picos are insanely popular and this applies to all Pico projects, not just this one.
Looks like a great card!
Anyone who has done a PCB run already at this side of ocean? (Europe)
I am interested.
The parts I ordered from DigiKey came today so I assembled two Apple II VGA cards from the PCBs skate sent me... I need to get a nut and bolt for them for the voltage regulator and I still need to program the firmware and test them but they're assembled. I need to order a couple VGA -> HDMI adapters now I guess. Super nice boards and an easy assembly job. I'm looking forward to seeing beautiful RGB output and not dealing so much with NTSC -> HDMI adapters which can be kind funky.
a2vga.jpeg
Well, I built all the boards I have now. I just need to program the Picos and test them tomorrow. Oh, I need to stop at Home Depot tomorrow and buy some M3 nuts and bolts for the voltage regulator.
Awesome, looking good so far!
The regulator isn't being driven hard (i.e. shouldn't be getting that hot right away), you can surely test it for a short moment without it screwed down if you program the Picos. Not sure if you're actually worried about that before firing one up, or if you are just done for the evening :) Either way, looking forward to your result!
The heat sink pad is just there for retro-cosmetic purpose. The card consumes very little current and the regulator on my card doesn't even go above room temperature.
The one from AliExpress I mentioned in Post 50 on the previous page landed in Europe yesterday, which means I'll receive it within the next 2-3 days. I don't know if it's crap yet, but I'll test it as soon as I get it and let everyone know.
I may wait until the VGA -> HDMI adapter I ordered gets here on Wednesday otherwise I've got to dig out a monitor that has VGA input on it. I could do that but I am kinda running out of steam tonightt. I should have plenty of time to stop by Home Depot and get the nuts and bolts when I am out and about tomorrow.
Well, it looks like I am going to wait until the VGA->HDMI adapter gets here because I can't find a VGA cable around here. I know I've got at least a few of them somewhere but who knows what box they are in. It is probably just faster to wait until tomorrow when the adapter gets here than to dig through stuff and find a VGA cable.
I know how that goes. Last time I couldn't find a VGA cable I bought a 6 pack of them online immediately :'D
Edit: this is an absolute steal for a pro grade VGA to HDMI scaler. Someone needs to buy this as long as the scratches don't bug you / you can fashion a single voltage DC supply (Not mine / I already have one). https://www.ebay.com/itm/355081336867
Extron video processing products are amazing, especially if you can get them cheap secondhand. The RGB-HDMI 300 A also works for the IIGS very well, someone documented those settings on here or 68kmla. Also it has a 3.5mm jack for audio insertion to the HDMI signal, and can process component video on the VGA dsub to convert YPbPr to HDMI if configured in the menu in place of VGA/RGB input.
I've run into something weird... this is happening with all 4 of the cards I built... The VGA -> HDMI converter seems to work but I'm getting weird blocks that are stuck on the screen. And trying to go to HGR and HGR2 fail.
I'm not sure if there is a problem with the //e I am using, the 74LVC245s, all of which came out of the same batch, or the Picos, again, all of which came out of the same batch.
The block pattern is similar with all 4 cards but not exactly the same.
The //e seems to work with a composite -> HDMI converter.
Any one got any ideas?
a2_vga_problem.jpeg
I'm going to try a different //e next. I may order some different 74LVC245 chips too if that doesn't work.
Maybe try flashing a different image into the Picos? I'm pretty sure I used "applevgae.uf2" the first time. I just re-flashed one with "applevga2072023.uf2" and it gives inverse @ instead of blocks but otherwise similar problem.
I tried removing all the other cards except the disk controller, and it seems to make no difference.
Oh, I also tried the card in several different slots, that doesn't seem matter either.
I tried swapping around 75LVC245s between different sockets and one from a different card and it doesn't seem to change much either...
Guess I need to try it in a totally different //e...
a2vga_vga2hdmi.jpeg
Looking at resistor bands... I am wondering if somehow I put the wrong resistor for R9 on all my cards? My cards have different color bands than one of the other pics posted... I may need to pull one off and check the marking under it...
Looking at resistor bands... I am wondering if somehow I put the wrong resistor for R9 on all my cards? My cards have different color bands than one of the other pics posted... I may need to pull one off and check the marking under it...
Hmmm... not sure if that is wrong now...
Damn.
Wow, how did you get the VGA->HDMI converter before me?? :)
R9 should be the same color band as R11 next to it. All your brown 4-band resistors are correct. However the resolution of your pictures is not high enough to check the blue 5-band resistors, so you should check them with a multimeter.
You can use the 74HCT245 chip from your ESP32 SoftCard in each individual socket of the VGA card to possibly locate a bad 74LVC245 chip. As I mentioned earlier, this card works with 74HCT245 chips as well and they won't damage anything if used for a short period.
Also are C1, C2 and C3 100 nF on your card? I usually don't see such small size ceramic disk capacitors go up to 100 nF.
I would try the original authors firmware, while I doubt it will fix your issue, you may as well start with it:https://github.com/markadev/AppleII-VGA/releases
Also I can't help but wonder how that adapter is powering itself.
Can always start simple and check the pins of your regulator against ground to make sure 5v and 3.3v look happy.
Pages