Thanks, this is interesting.
Perhaps I can do something to improve that.

Having no option rom activated seems like an unusual state.  Why do you
have no option rom activated?

Steve

On Monday, February 9, 2026, B 9 <[email protected]> wrote:

> Virtual-T seems to be running too fast for me compared to real hardware
> (Tandy 200). I could be doing things wrong, so it’d be helpful if other
> people checked this out as well.
>
> Experimentally, my Tandy 200 takes 10 seconds to count to 3535.
>
> FOR T=1 TO 3535: NEXT
>
> When I do the same thing on Virtual-T’s emulated T200 it takes only 6
> seconds.
> Machine Time to count to 3535
> Genuine T200 10s
> Virtual-T 1.7 T200 6s
> Virtual-T 1.7 M100 5s
>
> Is the same thing true for other folks with real hardware? What about the
> Model 100 and Tandy 102 (or other more esoteric of the Kyotronic kin)?
>
> Second thing: REX# seems to slow my machine down significantly when I do
> not have an Option ROM activated. It is completely repeatable. Is this a
> known issue? I tried using the emulated REX in Virtual T, but I must have
> an old version as it only had REX and REX2 listed, not REX#, and those
> didn’t cause any slowdown.
> Machine and REX# setup Time to count to 3535
> Genuine T200 with REX# De-installed 10s
> Genuine T200 with REX# Installed, but no Option ROMs activated 16s
> Genuine T200 with REX# Installed and any Option ROM activated 11s
>
> Finally, here’s a program that makes it easy to run timing tests
> repeatedly.
>
> 0 REM Speed Check4 COUNT=3535 ' T200 takes 10s to 35355 PRINT"Counting up 
> to";COUNT6 PRINTTIME$10 T1$=TIME$20 FOR T=1 TO COUNT: NEXT30 T2$=TIME$: 
> PRINTT2$40 H1$=MID$(T1$,1,2)50 M1$=MID$(T1$,4,2)60 S1$=MID$(T1$,7,2)70 
> H2$=MID$(T2$,1,2)80 M2$=MID$(T2$,4,2)90 S2$=MID$(T2$,7,2)110 
> H2=VAL(H2$):H1=VAL(H1$)120 M2=VAL(M2$):M1=VAL(M1$)130 
> S2=VAL(S2$):S1=VAL(S1$)150 IFS2<S1THENS2=S2+60:M2=M2-1:GOTO 150160 
> IFM2<M1THENM2=M2+60:H2=H2-1:GOTO 160170 IF H2<H1 THEN H2=H2+12: GOTO 120180 
> H=H2-H1: M=M2-M1: S=S2-S1190 PRINT"Ran";COUNT;"loops in";200 
> PRINTUSING"##h##m##s";H;M;S
>
> Please let me know what you find. Thanks all!
>
> —b9
>

Reply via email to