The development took about 6 months - I had to search for information and make tough decisions (search for my posts on SE.EE and AD EngineerZone). I have learned a lot designing it, and very proud it worked properly at the first start. The board can contain either V9938 or V9958, has RGB, S-video and color composite outputs. It can detect frequency of the VDP and switch to respective PAL or NTSC mode on its composite output.
With V9958:
With V9938:
80-character mode over composite: not perfect, but characters can be easily recognized. Interesting, that image in PAL mode is better than in NTSC mode.
