Date : Tue, 04 Mar 2008 23:07:36 +0100 (GMT)
From : johan@... (Johan Heuseveldt)
Subject: TUBE chip, accessing 'Parasite' side - 16Mhz 65C02S
Hi David,
On Tue 04 Mar, David Warrington wrote:
> PROJECT CO-PRO
>
> There's been a lot of talk about building CoPros over TUBE in the last
> days,esp. 6809. There seem to be a lot of challenges, which is, of course,
> half the *fun*! But may I also suggest taking a look at a "modern 6502"
> also? They only cost $8 one off, and matching VIAs are also available for a
> similar price. I have been considering building a CoPro using a 65C02S ...
> but no time to follow through at the moment.
>
> The 65C02S is manufactured by WesternDesignCentre in both PIC and PLCC
> packages and will happily clock up to 24Mhz (this data according to WDC
> themselves, even though the "paper spec" is 14Mhz, they overclock easily).
> www.westerndesigncentre.com
This overclocking rate is new to me. Some static RAM is available with 55 ns
access time, which is 24 MHz I think.
I certainly know them from their web site. It's nice to know they are still
manufactured, but I haven't checked if some Dutch electronics shop can
deliver them to me easily, and if the price is still ok.
> At 24Mhz, that's 12x faster than a standard beeb (at 2Mhz), or 8x faster
> than standard 6502 second processor (at 3Mhz).
The Master CoPro is 4 MHz!
Actually I did give it a thought, but with these high speeds you must know
something more about electronics I suppose, wiring it all up and/or making a
PCB layout. It's defenitely more than glueing some logic together I recogn.
> If this all sounds *too easy* and not enough *fun*, one could think about
> paged memory on the CoPro rather than just a single memory map... and
> therefore run a modified BASIC with one 64K bank for program, and another
> 64K bank for variables.
Then I find a 65816 more acctractive, with 16 MBytes of SRAM! :-)
Johan
--
Johan Heuseveldt <johan@... >
aka waarland
The best place is a Riscy place
Predestination was doomed from the start.