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## Assembly Notes
1. You may build this board as if it is a general purpose ASCII interface. In
- You may build this board as if it is a general purpose ASCII interface. In
that case, you may want to avoid installing the 1x25 Apple2 keyboard header
if it interferes with the target keyboard matrix. Also, for use with a key
matrix that already has a diode for each key (or each row), you will need to
install jumpers across the footprints for diodes D1-D16.
if it interferes with the target keyboard matrix.
1. If you ARE building this board as an Apple 2 encoder, then you may omit:
1. OMIT Sol-20 connector J5
1. OMIT Custom connector J7
1. OMIT D17,D18,D19 - These are used for the "classic" keyboard matrix.
1. OMIT D7,D8,D15,D16 - These are diodes for rows 12-15, which are not used.
1. OMIT the serial out connector J3 if you do not plan to use a serial output.
1. OMIT the I/O connector J4, as all the I/O lines are routed through the
- This encoder is normally used with keyboards that have a diode per key. For use
with a key matrix with no diodes (such as the Apple 2 key matrix), cut the PCB
traces that short diodes D1-16, and install D1-16.
- If you ARE building this board as an Apple 2 encoder, then you may OMIT:
- Sol-20 connector J5
- Custom connector J7
- D17,D18,D19 - These are used for the "classic" keyboard matrix.
- D7,D8,D15,D16 - These are diodes for rows 12-15, which are not used.
- The serial out connector J3 if you do not plan to use a serial output.
- The I/O connector J4, as all the I/O lines are routed through the
keyboard connector.
1. OMIT RN1. Not needed since the microprocessor uses internal pullups.
1. If you will be using the keyboard with only an Apple 1 or Apple 2, then
- If you will be using the keyboard with only an Apple 1 or Apple 2, then
you do not need to install both the Apple 2 connector (J1) AND the Apple
1 connector (J2). You may install only the one you plan to use, and
reduce the risk of plugging into the wrong socket (and possibly damaging
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1. Solder the surface-mount microcontroller first. Be sure to match pin 1 to the
dot on the silk-screen layer.
1. Next, install the surface mount crystal, Y1. The orientation is not important.
1. Next, solder in the diodes D1-D7, D9-D14, and 20-D27
1. Install all the capacitors. These are all 0.1 uF ceramic capacitors with 0.1"
lead spacing. Many capacitors with 0.2" lead spacing are actually 0.1"
emerging from the body, bent to 0.2", and can be straightened back to 0.1".
1. Next, solder in the resitor R1 and Resistor network RN1.
1. Install DIP switch SW1.
1. Next, solder in the resitor R1
1. Install all the capacitors. Be sure to separate out the two capacitors for the XTAL
circuit from the other capacitors, the rest of which are 0.1uF bypass capacitors.
1. Install the In-circuit Serial Programming (ISP) header, J6. (right-angle, 2x3
0.100")
1. If you will be using the Apple 1 connector, install the DIP socket J1 (16-pin