That is pretty slow, wht kind of processor and motherboard/bios ?, software wise you can muck w/the low level r/w code, but it probally won't get you much, you will probally have to review the hardware 'design' and see if there is anything you can do there. Also did you use a logic analyzer or scope to determine the timing ???
Scope, DOS, 800 MHz -- I think -- PENTIUM. Program assy:
mov dx,port
mov al,data
lab: out dx,al
jp lab
Obviously something inserts a few hundred clk cycles.
I know the 188/186 has programmable wait states
but not hundreds.... <nbucska@pcperipherals.com>