^ 1280x1024 19" lcd - on the video you don't see the whole screen just the main rectangular gfx area of the title screen

keropi wrote:

Allright I made the video. First I centered the screen, ensured I get correct colors with KQ1 and recorded MM1988 in composite mode:
https://www.youtube.com/watch?v=H8XSFA9Yduo

I hope the video is good - anything else just ask retrocanada76 😀

It still makes no sense to me that the black pattern is failing. See whenever you have black stripes it fails. What is that ? Could it be possible that it's not actually black but dark grey instead ? That would explain...

retrocanada76 wrote:

keropi wrote:

Allright I made the video. First I centered the screen, ensured I get correct colors with KQ1 and recorded MM1988 in composite mode:
https://www.youtube.com/watch?v=H8XSFA9Yduo

I hope the video is good - anything else just ask retrocanada76 😀

It still makes no sense to me that the black pattern is failing. See whenever you have black stripes it fails. What is that ? Could it be possible that it's not actually black but dark grey instead ? That would explain...

Reminds me of the green issue I had which was caused by a tiny solder bridge on the ram chip.

this shouldn't be the case as it works with the EGA and the color composite happens before sending to the SRAM

Hello all

Big thanks to retrocanada76 for his great video scandoubler. I build one today and tested it with all my video cards including MDA/Hercules and CGA clone. Image quality is perfect at all!

But I have very interesting old soviet computer named "Poisk". This computer has almost CGA compatible video adapter build on discrete logic without using MC6845. So, video output is TTL CGA compatible. And your mce2vga converter display image propertly. But i see Jitter on pixels:
Youtube video: https://youtu.be/2no88SHgtI8 (text mode)
https://youtu.be/l8Kz0SOA_hI (graphics mode)

Do you think this is possible to do something?

I dump HSYNC, VSYNC, I, R, G and B signals using Saleae Logic 8 and save capture. If it help, you can dowload Saleae capture file from this link: https://yadi.sk/d/gwyTHsY83TW5UL

Tronix what happens is that the Poisk pixel clock is slightly different than the CGA. Even if you could manage to change the FGPA code to match this pixel clock, then the fpga board would have same jitter for regular CGA cards.

The CGA pixel clock is 14.3181Mhz and it comes from the motherboard.

Try to identify the poisk pixel clock

retrocanada76 wrote:

Try to identify the poisk pixel clock

Thanks for replay. Yes, you are right. Poisk use 15 MHz crystal for CLK, so CPU run at 5 MHz. I think pixel clock is also 15 MHz or similar, not 14.3 MHz.

retrocanada76 wrote:

if you could manage to change the FGPA code

I am newbie in FPGA, i am trying change PLL2 c0 clock to 120.0 MHz, but Quartus says: "Cannot implement the request PLL. Cause: requested mul/div factors not achievable". It is inpossible?

Thanks.

You have to disable all clocks and change the first to 120. But then I may not be able to set the others in the correct clocks.
so you will probably have to remove the MDA/HGC and EGA modules and make only one for the poisk frequency.

retrocanada76 wrote:

You have to disable all clocks and change the first to 120. But then I may not be able to set the others in the correct clocks.
so you will probably have to remove the MDA/HGC and EGA modules and make only one for the poisk frequency.

Thanks, i will try later. Should i change SRAM clock to 120 MHz too?

Not a requirement, but I starts to run less reliable above 115 that's why I left if around 114.

Wow i really need one 😀

matze79 wrote:

Wow i really need one 😀

Yes, you really do need one of these! I have sold several of these to VCFED.ORG Members. Send me a message and we can work out the details.

These will be available through Serdaco Shop soon, right?

ps: need one, too. 😁

derSammler wrote:

These will be available through Serdaco Shop soon, right?

ps: need one, too. 😁

yes, will be available soon 😀
pm me if you want to make a reservation
first batch will be 10 pcs

I pushed a new FW: right now CGA is always active, so even if you set the unit to MDA, when you connect to a CGA output it will switch to CGA. This is useful for people who use MDA and CGA, no need to configure the unit just plug into the video card.

But for EGA you still need to switch to CGA/EGA position. It would be more complicated to tell EGA from MDA and Hercules.

retrocanada76 wrote:

I pushed a new FW: right now CGA is always active, so even if you set the unit to MDA, when you connect to a CGA output it will switch to CGA. This is useful for people who use MDA and CGA, no need to configure the unit just plug into the video card.

But for EGA you still need to switch to CGA/EGA position. It would be more complicated to tell EGA from MDA and Hercules.

That is great news !!

Are there instructions for programming the FPGA board? I'm new to FPGA.

I've downloaded the Quartus software and installed the USB Blaster II driver. I downloaded the firmware from github, opened the CDF file, and hit the Start button. It says 100% successful. Is that all there is to it? I can't figure out how to do a "verify", as the verify box is greyed out.

Unfortunately, I don't seem to be getting any VGA output, so either I've soldered something up wrong or I've failed to program it.

Thanks,
Scott

smbaker wrote:

Are there instructions for programming the FPGA board? I'm new to FPGA. […]
Show full quote

Are there instructions for programming the FPGA board? I'm new to FPGA.

I've downloaded the Quartus software and installed the USB Blaster II driver. I downloaded the firmware from github, opened the CDF file, and hit the Start button. It says 100% successful. Is that all there is to it? I can't figure out how to do a "verify", as the verify box is greyed out.

Unfortunately, I don't seem to be getting any VGA output, so either I've soldered something up wrong or I've failed to program it.

Thanks,
Scott

I found a solution on Windows for those of us with the el cheapo USB Blaster.

1/ Install Quartus II v11 & the drivers (from supplied DVD)
2/ Install Quartus 17 "32-bit windows programmer only software" from the website
3/ run Quartus 17 programmer once, USB blaster likely will detect but not work, so quit Quartus
4/ in device manager, find the Altera USB blaster (it'll prolly have an exclamation mark), "Update the driver" using the driver in the Quartus II v11 folders (just do auto search).
5/ run Quartus 17 programmer and it'll reliably program everything without issues from the JLC file.

I hope this helps.

Turns out I was just programming the wrong file or an incomplete set of files. One of Keropi's posts in the thread showed me the way. The cdf file references the sof file. I needed to program the jit file. After programming the jit file, I have video!

Scott

retrocanada76 wrote:

Not a requirement, but I starts to run less reliable above 115 that's why I left if around 114.

Thanks for replay. I remove all other clock for EGA and MDA. This allowed me to make proper clock for Poisk 15MHz CGA. Thus, now i have two firmwares - one for standart CGA/MDA/EGA and one for Poisk CGA. Thank you! Great project!

BTW, a week ago i have a new interesting computer named "Robotron EC 1834". He also has a non-standard (MDA?) video card . Pixel clock is 18MHz. Your MCE2VGA displays the image without modification (with Jitter). But now I know what to do! Thanks again.