14 Feb
2007
14 Feb
'07
8:59 p.m.
Are the programs from the SWTPc 6800 interchangeable with the Altair 680?
Is there a good web reference that compares these two?
16 Feb
16 Feb
4:29 a.m.
B. Degnan wrote:
Are the programs from the SWTPc 6800 interchangeable
with the Altair
680? Is there a good web reference that compares these two?
there are several differences that affect interchange between
the mits 680 and the swtpc
the acia address is $F000 in mits
swtpc uses a bit banging PIA at $8004
swtpc uses the mikbug monitor ROM, mits uses a custom
monitor rom that looks a lot like minibug.
(later swtpc systems used SWTBUG and an ACIA)
swtpc has a scratchpad RAM at $A000 mits has all RAM
contigous starting at $0000
swtpc runs at aprox. 900kHZ mits runs at 500KHZ
mits has a configuration register at $F002 swtpc doesn't have one.
both systems use KC standard cassette at 300baud and motorola
S1-S9 records
joe
7:54 a.m.
B. Degnan wrote:
> Are the programs from the SWTPc 6800 interchangeable with the Altair
> 680? Is there a good web reference that compares these two?
I always kind of wondered why MITS bothered to produce the 680. Given the
timing of it after the SWTP 6800 and their own Altair, it seemed more like a
backwards step. Just trying to take market share away from SWTP perhaps?
10:42 a.m.
Brent Hilpert wrote:
ISTR the mits 680 was advertised before the SWTPC was. The design must
have been
underway at the same time as the SWTPC. I don't think it was built to
under cut
SWTPC. In that time frame no one knew what processor would come out on top.
Hedging your bet was pretty common.
I've often wondered why the 680 ran at such a slow speed. I find it hard
to believe
500khz was the design target when 2mhz parts were available.
The speed, the lack of option boards and software tells me MITS was never
serious about the 680.
joe lang
B. Degnan wrote:
>Are the programs from the SWTPc 6800 interchangeable with the Altair
>680? Is there a good web reference that compares these two?
>
>
I always kind of wondered why MITS bothered to produce the 680. Given the
timing of it after the SWTP 6800 and their own Altair, it seemed more like a
backwards step. Just trying to take market share away from SWTP perhaps?
5:56 p.m.
On 15 Feb 2007 at 23:54, Brent Hilpert wrote:
I always kind of wondered why MITS bothered to produce
the 680. Given the
timing of it after the SWTP 6800 and their own Altair, it seemed more like a
backwards step. Just trying to take market share away from SWTP perhaps?
I recall that my impression about the MITS 680 was that it was aimed
at a lower-budget market than the 8800. They always seemed sort of
lukewarm about it--I don't think they thought that SWTPc 6800 offered
any serious competition to the 8800.
6526
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4 comments
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billdeg＠degnanco.net -
cclist＠sydex.com -
hilpert＠cs.ubc.ca -
jclang＠notms.net