2 Jul
2012
2 Jul
'12
11:17 a.m.
From: mcguire at neurotica.com
---snip---
Probably. Back in those days the communication resources between
designers were nowhere near as effective as they are today, leading to
many more instances of "designing in a vacuum" with just the datasheets
to go by, and nothing else. I don't miss that AT ALL.
-Dave
Some of the app notes from the manufacture were wrong as well.
I found an error in one of the notes for the 4040 Intel part. The
reset was inverted relative to the original 4004 and needed an inverter
to match the 4001 and 4002.
They'd place a transistor between the 4040 and the other chips.
The problem was that the 4040 would start running for 2 or three
cycles before the 4001s were released.
It wouldn't always reset right. In the app note, they said to put
3 or 4 NOPs at the begining of the code. This work most times
but failed on about 5-10% of the boards I worked on while
at Intel.
It just require changing the order, release the 4001s first then
the 4040.
Dwight