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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: OSS542 on November 24, 2008, 04:37:48 AM

Title: A4000T DMAC question
Post by: OSS542 on November 24, 2008, 04:37:48 AM

A quick silly question.....

Having never seen the inside of an A4000T before, I am wondering if these used a DMAC anywhere ?  I can see a Buster 11 and a Ramsey 7, but no DMAC.   Perhaps they did not use one .  Does anybody know about this ?

OSS542

Title: Re: A4000T DMAC question
Post by: Zac67 on November 24, 2008, 07:27:08 AM

Sure it does, the same Super DMAC (http://bboah.amiga-resistance.info/index_e.html) as A3000/T.

Title: Re: A4000T DMAC question
Post by: OSS542 on November 24, 2008, 08:47:00 AM

I had thought the same, but I don't see it on the board.  I have looked up a number of large images of other A4000T boards, and don't see it there either, nor any socket for it.
I was thinking perhaps they didn't use it in that model.

Title: Re: A4000T DMAC question
Post by: x56h34 on November 24, 2008, 03:50:36 PM

A4000 (both desktop and tower) does not use the DMAC chip, however it does use RAMSEY (ver. 7).

Title: Re: A4000T DMAC question
Post by: Zac67 on November 24, 2008, 10:21:20 PM

Doh - was actually feeling very positive about this... Sorry for the misinfo.

As it seems the 710 doesn't require an external DMA engine and can drive the address bus by itself.