Hello Brent,
 BB> ...a single timer tick is too long.
          ^^^^^^^^^^^^^^^^^
 BB> What else can I use as a timer so that the speed is the same on all
 BB> machines?
 BF> ...programable timer... I just happen to have
 BF> the right book for you here then. Pc Programmer's Guide to Low-Level
 BF> Functions and Interrupts, by Marus Johnson...
 BF> ...int 08H is called 18.2 times a second...
     Thanx for the detailed help, Brent. I was trying not to use that timer
     because I wanted greater resolution than 1/18 sec.
     I will save the data you posted though.
     Here is what I do have for using that timer in a round about way.
     It looks in the bios area of memory instead of using an interrupt.
delay   equ  1                  ;for example
timer:                          ;Wait CX clock ticks
push    ds
mov     cx, delay               ;X/18 second
mov     ax, 40h                 ;point DS to BIOS
mov     ds, ax
_wait:  mov ax,ds:[6Ch]         ;get low word of tick counter
wait1:  cmp ax,ds:[6Ch]         ;wait for it to change
je      wait1
loop    _wait                   ;count CX changes
pop     ds
ret
Kind regards, Barry
---------------