OK so it's not PIC but we have had some threads recently with regards to the GameBoy and the DSO add-in featured in Elektor (incidentally the January edition is to feature a prototyping board) Have a look at this site. They are producing MP3 players for a Gameboy. http://www.songpro.com/ If it can be done with a Z80................ My guess is that there is an MP3 Encoder in the cartridge. Which raises another question Why do we DECODE Analogue to Digital and ENCODE Digital to Analogue? Why does my gut say I should ask that question? :-) Oh, what the hell, Where there's Methane and Matches there's Flames. Regards Chris PS. No doubt some bright spark will point out that as well as Methane, Oxygen is also required for a flame, And another glowing ember will demonstrate that a surface rougher than wet tripe is also required to ignite the match 8-) -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads