VG30ET...Anyway, there are a number of programs you can use. I like a program called LiveEdit. RomEditor works ok too and you can never go wrong knowing how to use a regular hex editor. Check out http://forum.ztechz.net/ for some info. There is a lot of info on tuning the z32 and very little on the z31 but most of the z32 stuff applies to the z31. Aim me if you need more info.