Re: DD2 & 3

From: silverdr_at_wfmh.org.pl
Date: Sun, 7 Jul 2013 20:51:28 +0200
Message-Id: <874EE412-0F91-435F-96F3-205CC13855CA@wfmh.org.pl>
On 2013-06-19, at 10:24, Nicolas Welte wrote:

> Unfortunately DD3 on the 157x drives uses 2MHz all the time to improve loading speed, even in 1541 mode! This breaks compatibility with most custom loaders, so you end up disabling the board with @X- most of the time, if you want to load multi file games or watch demos.

Ah, I recall parts of our discussion some years ago and how I was surprised that you had this sort of compatibility problems while I hardly ever had to disable my 1541 DD2...

> An improvement could probably be made by porting the DD3 ROM of the 1541 to the 1571 ...

What would this change? Isn't the problem mostly cycle/timing related? You don't change the external clock with software in such case.. 

> BTW, do you know about the arm2iec SD card drive? It also supports the Dolphin DOS parallel cable, and the loading speed is unbelievably fast (IIRC less than 2 seconds for 202 blocks on C64)!

Wow! That's like IDE64's league!

> http://www.sd2iec.de/Hardware/
> 
> So you can build a nice Dolphin DOS system now with your boards, and have fast access to SD cards :)

No, I didn't know about it but that's something I've been looking to for years now!! I had high hopes for 1541U (-II), which should be able to cope with it easily but the parallel support never materialised there so far :-(

Does anyone sell those arm2iec units? Ingo, maybe?

-- 
SD!
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Received on 2013-07-07 19:01:49

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