[coco] 6309 speed

[farna at att.net]

Yeah, In my foggy memory I seemed to recall disk I/O timing to be fixed to work at 2 MHz with the CC3. But with the 1/2 there was an issue of if you wrote at 2 MHz you had to read at the same... or maybe I'm just tinking about the tape? No, I do recall an issue with the disk also. The fix may have been in the short controller vs. the long one though. I forgot! 

James, was the board running a 12MHz crystal and using a divider to run the 68B09 at 6 MHz though? That sounds more reasonable, though the ceramic package chips should run much higher than 2 MHz... with 12 MHz not out of the question. 

--
Frank Swygert
Publisher, "American Independent 
Magazine" (AIM)
For all AMC enthusiasts
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 -------------- Original message ----------------------

> Date: Fri, 12 Aug 2005 17:18:25 -0400
> From: jdaggett at gate.net
> Subject: Re: [coco] 6309 speed
> To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
> Message-ID: <42FCD9E1.32024.1830335 at localhost>
> Content-Type: text/plain; charset=US-ASCII
> 
> Curtis
> 
> WHere I used to work we used 68B09 based boards that were using 
> a 12MHz crystal. These were r unning 24/7 on the factory floor for 
> months at a time with no problems.
> 
> That correlates to a buss frequency of 3 MHz.
> 
> james
>