[net.micro.amiga] Questions about the sidecar

mende@topaz.RUTGERS.EDU (Mende) (07/22/86)

[---Yow!  I'm Hungry ... Is there anything good to eat here?---]

  I have a few questions about the sidecar that is soon (so they say) 
to be released.   First of all, Does the sidecar have to be directly on 
the Amiga's expansion bus, or can you have it running off an expansion board 
like a memory board?  Does the sidecar have a 86 pin bus comming out of it?
If it does, does it pass the Amiga's full 1amp or does it use part of it?
  Second of all, I have head about using an IBM hard drive and partitioning
part of it as an amiga hard drive.  Does this hard drive use DMA or is 
it bound by normal I/O speeds?  
  Thanks in advance for asking all these questions, I am considering buying
a 1meg. board and do *not* want to buy it if it would be incompatable with the
sidecar.


				Bob Mende


UUCP: {anywhere}!{caip|topaz}!aim!mende
ARPA: MENDE@AIM.RUTGERS.EDU

cmcmanis@sun.uucp (Chuck McManis) (07/23/86)

> 
>   I have a few questions about the sidecar that is soon (so they say) 
> to be released.

I suspect if you call Commodore West Chester repeatedly about how great
it would be to have one of these, and how you would love to buy one they
would make sure it got expedited.

>                 First of all, Does the sidecar have to be directly on 
> the Amiga's expansion bus, or can you have it running off an expansion board 
> like a memory board?  Does the sidecar have a 86 pin bus comming out of it?
> If it does, does it pass the Amiga's full 1amp or does it use part of it?

Yes, the sidecar plugs into the 86 pin expansion bus and also "passes thru"
the Joystick/Mouse ports. But it does not promote the 86 pin bus thru.
Thus it is an "end terminal". (Note you also cannot plug the Mimetics(sp)
sound sampler into the joystick port on the sidecar since the box would
not fit. You would have to use a nine pin extender cable.

>   Second of all, I have head about using an IBM hard drive and partitioning
> part of it as an amiga hard drive.  Does this hard drive use DMA or is 
> it bound by normal I/O speeds?  

It is true that the Amiga can share the hard disk with the PC. Data is 
transferred through the shared memory interface but the shared memory
is not part of "chip" ram so the built in DMA channels can't be used
to copy it around. It is still at "hard disk speeds" though. As an 
interesting aside, the 1.2 docs have all sorts of references to "formatting
the hard disk partition." 

>   Thanks in advance for asking all these questions, I am considering buying
> a 1meg. board and do *not* want to buy it if it would be incompatable with the
> sidecar.
> 

At the BADGE meeting (the source of all this info) R.J. Mical indicated that
the sidecar had sockets for 2 Meg of *Amiga Ram*. Thus the side car is a
memory expansion card. There was no mention of "zorro" slots in the sidecar
only PC slots. And contrary to previous info on this net R.J. said that
you *could* plug in a PC graphics card and the Sidecar would recognize it
and use it rather than the shared ram. (I am not sure how useful this is
unless the card is an EGA card.) 

My conclusions : The sidecar can provide the Amiga with 2 Meg of ram, 
a hard disk, a battery backed up clock, and high speed math (via the
8087). That in itself makes it a good buy, add to that the ability to
run PC programs and it seems to be quite a deal. Now if we could
just get Commodore to get it out the door...

--Chuck McManis

--------------------------------------------------
#include <disclaimer/myopinions.h>
 These are only my opinions and what I have heard.

> 
> 				Bob Mende
> 
> 
> UUCP: {anywhere}!{caip|topaz}!aim!mende
> ARPA: MENDE@AIM.RUTGERS.EDU

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