From Mark Willis, Jeff King, Don McKenzie, Craig Lee
(A)--\/\/--+-----+-----+
# | |
# | |
(B)--\/\/--+--+--(--+ |
# # # #
# # # #
(C)--\/\/--+--+--+ | |
# | |
# | |
(D)--\/\/--+--------+--+
Where each ## in the diagram is actually two LED hooked "anti-parallel" like this:
|----|<-----|
-| |-
|---->|-----|
ABCD LED ON
---- ------
0000 none
1111 none
zzzz none
01zz 1
10zz 2
0z1z 3
1z0z 4
z01z 5
z10z 6
0zz1 7
1zz0 8
zz01 9
zz10 10
z0z1 11
z1z0 12
Questions:
James Newton replies: Now that I think about it: Yes, in a microcontroller z would represent a pin that had been set as an input.+
See also:
| file: /Techref/io/led/12w4pins.htm, 2KB, , updated: 2007/4/2 12:58, local time: 2012/2/8 03:53,
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Ashley Roll has put together a really nice little unit here. Leave off the MAX232 and keep these handy for the few times you need true RS232! |
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