NP-41 Emulator (may be)

[rprosperi]

(12-18-2015 04:44 AM)Sylvain Cote Wrote:  IBM-PC XT or AT -> 4.77 MHz at normal speed and 8MHz at turbo speed.
You normally ran it a 8 MHz except for games that needed the 4.77 MHz to run correctly.

Exactly what my machine did! I loved that machine, wish I still had it today.

On some clones, one also had to go "down" to non-turbo to use modems, as in some BIOS, the serial com depended on empty code loops, assumed to be at 4.77 MHz (initially, I typed GHz... then realized just how slow these were!).