16 Nov
2012
16 Nov
'12
8:57 p.m.
On 11/16/2012 8:10 PM, allison wrote:
4.77mhz is about as fast as 2901s will run without
pipelining.
I did an 8/16 bitter with 2901Cs and was profoundly disappointed.
How ever in hindsight, memory speed and bus width ( 8 bits ) was the
limiting factor in speed back then.
Add length like 20 or 36bits makes for problems like
devices like disks
as most available will be 8 or 16bits. Then again with large disks
half word splits will fit. Makes it troublesome to do 12 or other odd by
current standards lengths for words.
Disks don't care what bits they get. With my limited knowlage, interface
chips where made for the upcoming 8 bit micro's, other machines still
relied on racks full of equipment.
As to PC killer, that was never needed, the pc was
killing itself with a
cpu that
was 8080 with a bag on the side. I always felt that the 8086/88 was a
market successful while failed design. Maybe why I used PDP11s and Z80s
till 1991 when 32bits made the scene at least interesting. The PC was an
appliance, not the latest computing tech.
The computer market, did need a machine
with more the 64K and only Motorola
and Intel had a product that could sell in personal computer. All the
other chips
came out just too late.
Since when is the latest, allways the best. I still favor analog audio
media,
and film for photos, and REAL IBM keyboards.
Allison
Any how since I am doing this computer as hobbie,I can play with the design
as "what if" and get a feel why computers ( crappy as they be in some ways)
are the way they are from that era in time.
Ben.