Maarten ter Huurne schreef:
> At 07:03 PM 8/24/98 +0200, you wrote:
>
> >I know that the clockspeed of the MSX-computer can be increased with a
> >'special' upgrade. In the past such 'upgrades', increasing to +/- 7 MHz,
> >existed and could be bought.
>
> The normal MSX Z80, which runs at 3.5MHz is replaced by a Z80 (Z80H) which
> runs at 7MHz. The clock cristal is replaced by a 7MHz one. Finally clock
> dividers are installed for the hardware that cannot handle a 7MHz clock.
>
> >Does anyone know of the existence of such upgrades or knows where I can
> >find such schematics? Or any information?
>
> Maybe Sunrise Hardware Service?
>
> Bye,
> Maarten
>
>
almost like that.
the clock signal is normaly deliverd by the VDP (exept for the nms8280)
you replace this clock signal by a clock from a Z8581
this is a little oscilator / devider witch can switch between 7.14 Mhz and 3,57
Mhz without
loosing clock pulses.
when you access a divice witch can not handle 7.14 Mhz you let him swich back to
3.57 Mhz
with a little delay.
so when you acces the VDP or the diskdrive it will automaticly switch back.
erik de boer
--
****
MSX Mailinglist. To unsubscribe, send an email to [EMAIL PROTECTED] and put
in the body (not subject) "unsubscribe msx [EMAIL PROTECTED]" (without the
quotes :-) Problems? contact [EMAIL PROTECTED] (www.stack.nl/~wiebe/mailinglist/)
****
