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More README cleanup

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Dave 2020-04-14 00:53:27 -05:00
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hardware/interface-ascii-atmega2560/README.md
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@ -93,26 +93,4 @@ those diodes. Otherwise the diodes do nothing.
If you are attaching a keyboard with a diode per key, then the diodes on the keys perform the same function, in addition to preventing "ghosting", so the per-row diodes do not need to be installed.
### DIP switch and associated diodes
The DIP switch is optional. If you don't want to be able to set options via the
DIP switches, you can set all your preferences in the firmware, or just accept
the default behavior, and skip the DIP switch and Diodes D17-D20 and D24-D27.
### Second 74LS138 multiplexer (U4)
Only needed if you have more than 8 rows (including the DIP switch).
### The 74LS07 hex buffer (U5) and pullup R6
The 74LS07 is only needed if you are using LED2 or LED3 on the keyboard, or the OUT2 open
collector output.
### Diodes D21, D22, D23
Some keyboards may not wire all keys into the matrix. For example, some other
interface modules may assign special hardware functions to certain keys. Those
keys are brought directly to the keyboard connector. For the classic keyboard,
the POWER key, the '@' key, and the RUBOUT key are not directly wired. This
module wires them into the matrix via D21, D22, and D23, respectively. For
keyboards with no separately wired keys, these diodes may be omitted.
### Resistors R1, R2, R5
These resistors provide current limiting for up to three keyboard LEDs. If no
keyboard LEDs are installed, then these resistors can be ommitted.