🚀 go-pugleaf

In article <1992Sep11.193305.20265@rhrk.uni-kl.de> m_sattle@tangram.informatik.uni-kl.de (Matthias Sattler) writes:


>
>I just replaced the 36 MHz quarz on the board of my A5000 by a 60 MHz one. This
>had several results on my A5000.
>1.) The VIDC is clocked faster so I could do 1024x768 60Hz (if your vidc
>can do this)
>2.) Mode 31 is 93 Hz (if your monitor can do this...)
>3.) 800x600 256 Colours isn't possible any more
>4.) There are problems with very low-res modes like mode 0, but I don't
>know why
>5.) The computer gets remarkably faster... >22000 Dhrystones in mode 21, 28 
>    (with CPU 30 MHz) and I don't know why as well.

The 36MHz clock also clocks the memory system. It's divided by 3 inside MEMC
(effectively). So using a 60MHz clock means you are now running your memory
system at 20MHz. Obviously this has a beneficial effect on your machine
speed...if it continues to work.


___________________________________________________________________________
Ashley Stevens, Design Engineer, Acorn Computer       astevens@acorn.co.uk      
Temporarily encamped at ARM Ltd...                    astevens@armltd.co.uk