Today I finally managed to transfer the prototype of the video board to target PCB. The design was made in Eagle as usual. The traces layout was printed on a laser printer and transfered using an ordinary iron. The boarw was etched in B327. During the initial run of the board a problem came out: a black screen on the monitor connected to it. A logic probe connected to the VGA socket revealed that there were no vertical pulses at all. After checking the solderings I found out that pin no. 35 of XC9536XL was floating unsoldered. After fixing it, the whole system started and worked perfectly. Below you can see the schematics , board layout design I made and of course the assembled board and the whole system running some tests:
Below is a photo of a complete set up to this day. Plans for the future ? To start the development of a ROM Monitor program, and some experiments with AY-3-8912 sound generator chip.
8-bit computer from scratch. 
Hi.
Great project .. good to see people making homebrew computers !
Must say that probably using a legacy video Chip (V99x8 etc) may of been easier than using a CPLD…
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Hi Lez, thanks for comment, glad You like my work. Yes, it wolud be easier, more elegant and the effect would be better, however at the time I started the design I couldn`t get my hands on any VDP chip really, so I started developing my own solution. The good thing is I lerned a lot in the process…
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