1702A programming (was Bugbooks - Mark 80 )

From: Dave Dameron <ddameron_at_earthlink.net>
Date: Tue Jan 26 19:07:39 1999

At 10:10 AM 1/26/99 -0800, Dwight wrote:
>Dave Dameron <ddameron_at_earthlink.net> wrote:
>> At 11:10 PM 1/25/99 +0000, Tony wrote:
>
>> The 1702's had 10% of the program duty cycle of the 1702A, so took 10x
>> longer to
>> program. The voltages were the same. I don't know what actually was
revised on
>> the chip, larger output/program transistors?
>> -Dave
>
>Hi Dave
> The 1702A's also required that the address be complemented before
>the Vdd and Vgg were brought low. The 1702's didn't seem to need
>this and Vdd and Vgg were left at there low states the entire time.
>This also is a problem because the programmer I have doesn't
>switch Vdd and Vgg.
>Dwight
>
Thanks,
The Intel booklet I have has a 1702A programmer, and it implies it is
compatable with the 1702 with a lower duty cycle. So the 1702 _could_ work
with
the address complement step and switched Vdd, Vgg, but the 1702A requires
these.
I looked in my collection and found only 1702A's. Have been thinking about
building a programmer for when I ever build a 8008 system, but the Intel
one is fairly involved. There was a simpler one in the Feb. 1978 issue of
Popular Electronics. Sone things I prefer about the second, it used a
counter and shift register to control the timing instead of monostables.
-Dave
Received on Tue Jan 26 1999 - 19:07:39 GMT