"Matthew T. Russotto" schrieb: > Phi1 is an output, I think. > Apple's phi1 is the complement of the phi0 signal that drives the 6502. The 6502 itself generates a second phi1 singal that is the complement of its phi2, but this signal is not used. Therefore, phi2 is not available at the Apple II slot, if you want to use 65xx peripherals you have to generate it manually. Patrick