Tony Duell skrev:
>> Tony Duell skrev:
>>
>> >> I don't think I could form any relationship to a 4-bitter, either. I
>> >> woul=
>>
>> >Oh, there are a lot of them about. Of course it depends what you mean by
>> >'4 bit', but if that's the ALU/bus width, then the HP Saturn processor
>> >(used in the 71B, 28, 48, 49, etc, etc, etc) is a 4 bit chip. And I
>> >certainly like those machines (and yes, IMHO they are computers rather
>> >than calculators).
>>
>> I have no idea what you're on about. =)
>Just about every HP calculator since the HP71B has been based on a CPU
>called the Saturn (OK, the HP6S and HP30S aren't). This chip has a 4 bit
>ALU and external bus, but with 64 bit data registers and a 20 bit address
>width.
I know there's a Saturn emulator, but I thought that emulated a PA-RISC. =)
>> Besides, a 4-bit address bus seems utterly, utterly limited.
>Who said anything about a 4 bit address? Address width != ALU width in
>general...
Ah yes, ALU is arithmetic, not address. 8-bit ALUs usually have a 16-bit
address width, right?
As you probably can see, I've never been into lowlevel stuff.
>The Saturn works with 20 bit addresses. Memory is 4 bits wide, so the
>Saturn can address 1Mnybbles (or 512K bytes). Some modern machines
>(HP49G, for example) have bank-switching hardware to extend this further.
Why would you need more than 512K?
>> >> dn't
>> >> mind a 64-bitter for NetBSD purposes, though. 26-bitters are also on my
>> >> w= ish list. =3D)
>>
>> >26 bits? I can't think of a machine with a 26 bit data path. I believe
>> >some ARMs have a 26 bit address bus, but that's hardly a 26 bit machine.
>> >Now 24 bit machines can be interesting...
>>
>> Oh no? Finding an ARM-based machine around here is about as easy as finding
>> a
>What 26 bit machine were you thinking of?
The old Acorn Archimedes machines.
I'm sbscribed to the NetBSD/arm26 list, and I seem to recall that registers...
Oh, forget it. I'm a know-nothing when it comes to the Acorn.
>> live condor in the northern hemisphere.
>> What feature about the older ARM processors is 26 bit?
>In some cases, I believe the address bus was 26 bits wide.
What a nice, round figure.
--
En ligne avec Thor 2.6.
The object of this game is to take an ordinary guy and make him into a Pimp
Master. You start off in your home town.You'll gradually build up cash and
prostitutes,until you wipe out the other pimps in town. Then,it's time to move
on to another,bigger city,and do the same.
Pimpin' ain't easy, upcoming game from Delsyd Software
Received on Wed Nov 15 2000 - 14:40:35 GMT