Don FWIW I am using an original IMSAI Parallel ports 8212 driven board in my system with Z80 @ 10 MHz. Also with 8086, 68K e John
Sent from my iPhone
Speaking of the Intel 8212. I've only been able to find the 3Mhz
version.
Did Intel produce a faster version? I'm looking for a 4Mhz version
for use
in the FP mini project.
On 08/20/12 05:37 PM, Richard Cini wrote:
The 8212 is a weird kind of chip because it's a
multi-function chip designed to eliminate 2-3-4 different
chips in an 8008/8080/8085 system. It includes an 8-bit
D-type latch, address selection logic and an interrupt
generator. The data book I have shows it as being used as a
status latch for the 8080, a standard gated buffer, a
bi-directional buss driver (with two chips), an interrupting
input port, a port to jam a RST instruction into the data
buss during an interrupt acknowledge cycle, an output port,
and an address buss latch. So, I guess it depends on the
circuit whether you can replace it with another chip or not.
There was also an 8228 system controller chip which
performed a similar buss status latch using WR, DBIN and
HLDA plus the data buss to provide a bi-directional data
buss driver and control signals (INTA, MEMR/W, IOR/W). There
is a 6-part article on my Web site from Popular Electronics
(9/81) that shows this setup.
Rich
--
Rich Cini
Collector of Classic Computers
Build Master and lead engineer, Altair32 Emulator
Thanks Rich. Any ideas for Intel 8212 substitutions?
On Mon, Aug 20, 2012 at 4:59 PM,
Richard Cini <rich...@verizon.net>
wrote:
Don --
I have used the LS367 as a substitute with no
apparent problems.
Rich
--
Rich Cini
Collector of Classic Computers
Build Master and lead engineer, Altair32 Emulator
http://www.classiccmp.org/cini
http://www.classiccmp.org/altair32
On 8/20/12 7:54 PM, "Don Caprio" < ilv...@gmail.com>
wrote:
>
>I'm looking for substitutions for IC 8T97 (HEX
3-state buffer/bus driver).
>
>The 8T97's are expensive (~$5).
>
>I've seen suggestions that the following are
substitutions. Does anyone
>have experience
>with these substations? Are all adequate? Which
would be the best choice?
>
>8097
>74367
>MIC6887
>
>Jameco has the 74LS367 for $.89 cents, Anchor
Electronics $.46, Abra $.39.
>
>Where is a good source for the Intel 8212? These too
run in the $5 for
>pulls.
>Is there a suitable replacement for it as well?
>
>Thanks.
>
--
-------------------------------
Don Caprio cap...@uxpro.com
http://www.uxpro.com
(925) 240-UNIX
--
Don Caprio
ilv...@gmail.com
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