The ESP32 SoftCard for the Apple II

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Xanxi wrote:...1/ The ESP32
Xanxi wrote:

...

1/ The ESP32 Softcard has its composite output connected to a RetroTINK 2X and to my HDMI monitor. The problem is that the output shows flickering lines, prominently on the lower part of the screen but also toward the top. I have read about the 1.54 MHz signal interfering with the output in the previous pages.

...

2/ About WiFi on the ESP32 Softcard: I can connect to my network, I can launch FTPSERVER and connect to it anonymously. The problem is that either I can't see the directory contents, or the board crashes completely if I try to upload something to the card. What am I doing wrong? I have already tried several FTP clients.

...

 

Hi Xanxi,

 

There was an Apple IIgs video flicker issue back in 2023 discovered by sugix8, but with his help it was fixed completely by v2.0 of the firmware. Can you post a picture or video of your flickering? Often it is possible to determine the interfering frequency simply by looking at it. Does it happen with all the other expansion cards removed? Also, if I am not mistaken, you have an Applesqueezer accelerator on the motherboard running at 3 MHz, correct? Can you slow it down to 1 MHz to see if it still happens, or is 3 MHz the lower limit? Does it happen with a regular composite monitor, or just the RetroTINK? Does it happen with all the supported video standards: PAL, NTSC, PAL60 and NTSC50, or just some?

 

The ESP32 SoftCard cannot output VGA, only composite.

 

Regarding the FTP server problem, what operating system are you using and can you name a couple of FTP clients that it happens with? Hopefully I can find one of them for Windows and try to reproduce it.

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I would LOVE if the card

I would LOVE if the card could do VGA output, as composite out on my Apple //e is not good either on my LCD monitor.  It may be fine on a CRT, but I don't have one, and I'm not going to buy one of those time bombs at this point.  I have a VGA card, which works great, but I cannot use the ESP32 with it.

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The Applesqueezer cannont go

The Applesqueezer cannnot go lower than 3 MHz, but can be deactivated. I have done that and the flicker is the same.

 

I will try to remove the cards one by one later, but for now i have tried my spare green phosphore Apple monitor. The flicker is there but is very faint due to the own flicker of the monitor.

 

Here is a video i have made on the ASUS LCD in HDMI out of the RetroTinker.

 

It is the same with all PAL or NTSC modes (50 or 60 Hz).

 

https://youtu.be/BXXoJklmCeM

 

As for VGA output, i have read that the ESP32 chip could do it (but not HDMI). Here is a link https://github.com/bitluni/ESP32Lib For now the ESP32 Softcard can't do it of course.

 

 

About the ftp issue, from the PC i have only used FileZilla. From other retrocomputers (Amiga), i have used other FTP clients (AmiFTP, AmFTP, AmitradeCenter) with same results.

I have also noticed that trying to connect to a WiFi network with the wrong password also makes the card to crash. 

 

 

 

 

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Xanxi wrote:The Applesqueezer
Xanxi wrote:

The Applesqueezer cannnot go lower than 3 MHz, but can be deactivated. I have done that and the flicker is the same.

 

I will try to remove the cards one by one later, but for now i have tried my spare green phosphore Apple monitor. The flicker is there but is very faint due to the own flicker of the monitor.

 

Here is a video i have made on the ASUS LCD in HDM... https://youtu.be/BXXoJklmCeM

 

Wow, this is heavy noise! Looking at the picture you posted on Facebook, it looks like you have a lot going on.

 

This noise could be coming from a bunch of different places, including:

 

  • The unshielded PSU. Is this an aftermarket one or is it the original without the cover? Is it possible to shield it and see if anything changes? If not, can you try putting the ESP32 SoftCard in a slot that is furthest away from the PSU?
  • The HDMI card being too close. The Pico can be very noisy. Can you try moving to a slot that is further away or removing it completely?
  • The Applesqueezer GS accelerator can be the source of the noise as well. I don’t know if disabling it turns it off completely, or it simply leaves it “idling”.
  • Any of the other cards that are also plugged-in.

 

One thing you can do is try to drown the noise by increasing the video signal level of the ESP32 SoftCard. It is controlled by the first blue potentiometer labeled VIDEO LEVEL. Simply rotate it further clockwise. This will increase the overall brightness, which you can then readjust from the monitor.

 

I cannot reproduce the crash when you enter a wrong Wi-Fi password. Can you send me a PM with the name of your Wi-Fi network? Perhaps there is something special about the name.

 

I downloaded the FileZilla FTP client and there is indeed some issue with it, which I am investigating further and will provide a firmware update as soon as I fix it.

 

I am posting your picture from Facebook here for reference, I hope you don't mind:

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CVT wrote:...I downloaded the
CVT wrote:
...
I downloaded the FileZilla FTP client and there is indeed some issue with it, which I am investigating further and will provide a firmware update as soon as I fix it.
...

 

I investigated this and it's not really a bug. The issue is that the FileZilla FTP client uses multiple simultaneous connections, while the FTP server of the ESP32 SoftCard only supports one. So to make it work, you simply need to limit the number of simultaneous connections to 1. Both Active and Passive modes are supported, but Active mode might be blocked by a firewall, so it's always better to use Passive. 

 

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Hi. I have made some more

Hi.

 

I have made some more tests as you suggested.

 

About the PSU, it is third party as it is a picoPSU 90 (design from Tindie) with a good quality power brick outside the computer. Since i have replaced the PSU, it has been working great as far as i can tell.

 

So i have removed the A2FPGA, the UthernetII, the Number Crusher Reloaded, and it hasn't changed anything.

I didn't remove the other card as they are needed to operate the computer anyway (CFFA3000 +++).

The squeezer, i can' t remove either as i don't have the original CPU at hands. I guess that even when deactivated the squeezer is still emulating the CPU.

 

I haven't moved the card on other slot because i can't use it in another slot anyway with my combo of cards and cable management limits.

 

I have tried to add some ferrites to my cables, especially the RCA cables going from the ESP32 softcard to the RetroTink but the issue remains. I have let the ferrites in place now as they can't hurt anyway.

 

I also suspected that the Wombat could interfere because i noticed more noise (or differences in the noise aspect) while hitting the keyboard. Actually, with the regular adb keyboard and mouse, it is the same.

 

Turning up or down the potentiometer of the video signal didn't solve the issue either. On the contrary, the picture seems more jittery when rotating a lot clockwise.  The GABE bluetooh adapter for the gamepads is also not responsible as it was disconnected during those tests.

 

However, i have also tried the output on a very small black and white CRT integrated into a portable radio/CD player that i keep at home. When lowering the contrast to get a true black screen with white letters i can't see the artifacts no more. I can't try the same on my ASUS LCD as the OSD won't let me change anything when in HDMI mode, surprisingly.

 

I guess the LCD monitor is no good for this board, or that there is too much noise from the GS mobo itself (or the squeezer, or the PSU) and that i will have to live with it.

 

I will test again the FTP issue later.

 

Thanks!

 

 

 

 

 

 

 

 

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Xanxi wrote:...About the PSU,
Xanxi wrote:

...

About the PSU, it is third party as it is a picoPSU 90 (design from Tindie) with a good quality power brick outside the computer. Since i have replaced the PSU, it has been working great as far as i can tell.

...

 

When you use this PicoPSU-90 DC-DC converter + power brick, is your Apple IIgs still grounded? In other words, is there a direct electrical connection between the ground pin of the power outlet in the wall and the chassis of the Apple IIgs? If it is not, grounding it might help.

Ferrites over shielded coaxial cable will not have any effect. The noise is most likely being propagated through the Apple IIgs bus.

The CFFA3000 is also is not the cause. I have one myself and have not seen it to cause any noise in my Apple IIgs.

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Well, i don't know.The

Well, i don't know.

The adapter is connected just like this in this picture from Tindie https://ibb.co/9kmsf1Hg

 

Then i have used an external brick either with two prong plus or three prong plug with same issue.

 

I guess the Apple PSU is in contact with metal parts of the case but apparently not this one.

 

How could i do? Running a cable between the ground plus and a small metal part on the border of the case is enough?

 

 

 

 

 

 

 

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Xanxi wrote:...How could i do
Xanxi wrote:

...

How could i do? Running a cable between the ground plus and a small metal part on the border of the case is enough?

 

Yes, just to test if the noise gets reduced you can run a single wire from the ground pin of a power outlet and connect it to the metal chassis of the Apple IIgs. There should be a connection between the metal chassis and the shielding of all coaxial cables already.

 

Important: Make sure you are connecting the Ground (green arrow below) and not the Line or Neutal:

 

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Ok, i have type E wall plug

Ok, i have type E wall plug here.

So i have touched the metal port of the RGB port and the ground of the type E plug with the multimeter with the computer turned off and i got a continuity beep. So i guess the computer is grounded.

 

 

Finally, as the CRT monitors seem to not show the issue after adjustments in brightness and contrast,  or very faintly, i think there is probably a very small issue into the signal which is amplified a lot by my attempts to get a numeric output with the HDMI converter and the own scaler of the monitor. That's unfortunate that i have too few desk space to have a permanent CRT connected.

 

 

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Xanxi wrote:Ok, i have type E
Xanxi wrote:

Ok, i have type E wall plug here.

So i have touched the metal port of the RGB port and the ground of the type E plug with the multimeter with the computer turned off and i got a continuity beep. So i guess the computer is grounded.

 

 

Would the output ground pin of the Pico PSU also have to be connected to the chassis as well?
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PicoPSU
Xanxi 
 
 
Have you or anyone else used this PSU to power your GS from a car?
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Not according to installation

Not according to installation instruction, anyway. As the computer is connected to ground, i think this is settled.

As for powering the GS from a car, i have no idea and can't think of why i would want to be doing that. Anyway my picoPSU requires a 12V external brick center + of 90W.

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Xanxi wrote: Not according to
I believe the output on my car’s 12V port is about 100W. Making a cable from the 12V port to a barrel connector with a positive centre pin should be relatively trivial. The only thing is when the engine is running, the voltage is running around 14V from the alternator so maybe I’ll need a 12V buck converter to make sure the PSU gets 12V no matter what. The thought of doing this is just for fun. The head unit I installed does have a composite input, so potentially it could be used as a monitor, assuming the GS’s NTSCish signal can sync up with it. The front passenger seat folds down with a solid surface which could hold a GS. It can potentially make car camping a little more entertaining
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lemonherb wrote: I believe
lemonherb wrote: I believe the output on my car’s 12V port is about 100W. Making a cable from the 12V port to a barrel connector with a positive centre pin should be relatively trivial. The only thing is when the engine is running, the voltage is running around 14V from the alternator so maybe I’ll need a 12V buck converter to make sure the PSU gets 12V no matter what. The thought of doing this is just for fun. The head unit I installed does have a composite input, so potentially it could be used as a monitor, assuming the GS’s NTSCish signal can sync up with it. The front passenger seat folds down with a solid surface which could hold a GS. It can potentially make car camping a little more entertaining

 

There is no need to do this. An empty Apple IIgs with the original PSU consumes under 15W. If you fill it with cards, maybe it can go as high as 50W. All you need is a 12V to 120V converter from Amazon for your car.

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PicoPSU 12VDC applications

I would probably have to look for a pure sine wave inverter if that were the case. But even so, there are some inefficiencies to convert the cars 12VDC to 120AC only to convert it back to DC again. 

The PicoPSU adapter seemed like a neat idea to go from DC to DC.  I happen to have the kit for my GS so I was wondering about other ways to use it aside from a desktop situation 

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lemonherb wrote:I would
lemonherb wrote:

I would probably have to look for a pure sine wave inverter if that were the case....

 

No need for it to be pure sine wave, since the first thing the Apple IIgs' switching PSU will do is convert it to DC. 

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Hi. Now the composite output

Hi.

 

Now the composite output has also been tested on an Apple A2M6016 monochrome monitor and artifacts are barely noticiable when contrast is setup good.

So, unfortunately, the composite to HDMI conversion and the non modifiable contrast on the LCD monitor are definitly emphasizing the noise issue on the picture.

 

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Hi. Me again. The issue is

Hi.

 

Me again. The issue is solved. It was the AppleSqueezer v2 all along. So far i tried to deactivate it by taking off the CPU acceleration and i thought it was enough, but the RAM was still activated because i needed some RAM to start my OS. Now i have received a new 8 GB RAM card and i could deactivate the AS completely and still have enough RAM, and the artifacts are 95% gone on the LCD, now very very faint.

So solutions are either :

- use a composite CRT and not an upscaled picture on LCD

or 

- deactivate the AS. The ESP32 Softcard won't start with the AS set to more than 3 MHz anyway.

 

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Xanxi wrote:Hi. Me again. The
Xanxi wrote:

Hi.

 

Me again. The issue is solved. It was the AppleSqueezer v2 all along. So far i tried to deactivate it by taking off the CPU acceleration and i thought it was enough, but the RAM was still activated because i needed some RAM to start my OS. Now i have received a new 8 GB RAM card and i could deactivate the AS completely and still have enough RAM, and the artifacts are 95% gone on the LCD, now very very faint.

So solutions are either :

- use a composite CRT and not an upscaled picture on LCD

or 

- deactivate the AS. The ESP32 Softcard won't start with the AS set to more than 3 MHz anyway.

 

Thank you for completing the investigation and determining the root cause. I really appreciate it, as I cannot possibly acquire all the different Apple II hardware that exists out there and instead rely on users like yourself.

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