14 Jan
1999
14 Jan
'99
4:14 p.m.
Hi Tony and all,
At 10:44 PM 1/14/99 +0000, you wrote:
I would strongly disagree with that, at least in
hardware. I've recently
been looking at some discrete-transistor logic circuits and the
creativity that went into their design (IMHO) exceeds anything that I've
seen done with modern 'black-box' chips. For example, I've seen a
keyboard encoder (8*8 matrix of keys to 6 bit binary + strobes + ...) in
about 20 transistors and as many diodes. Much, much more elegant than
throwing a microcontroller at it.
Yes, for example the Popular Electronics keyboard in ~1974 by Don Lancaster
and Southwest Technical Products used a few inverters (RTL) and transistors.
3 transistors sensed which of 8 columns a keyswitch was pressed, and these 3
transistors produced 3 of the ASCII output bits. The 8 row ouyputs produced
3 other bits. Much easier to "fix" than the MOS encoder chip, if that chip
was programmed for a custom matrix, such as the Heath H19 terminal.
-Dave