As with the Tape Panel I started by wiring all of the ground leads together for the LEDs and buttons then added a jumper so I could attach the ground(s) to one of the Expander's extra GND pins.
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I added limiting resistors to all of the lamps.
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Then I mounted a second Expander PCB to the back of the Finite State Machine Panel with two sided tape and connected all 16 of the purple status lamps to it. I had to change the I2C address for this board so it would not conflict with the first. There are jumpers for this.
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Here are all the connections made:
From | To |
---|---|
Lamps: C, B, A, READ, WRITE, MOVE, GOTO, A1, A0, Ab, B1, B0, Bb, C1, C0, Cb | Extender Pins: PB7, PB6, PB5, PB4, PB3, PB2, PB1, PB0, PA0, PA1, PA2, PA3, PA4, PA5, PA6, PA7 |
Transition Table Reader +5V | Extender Pins: VCC |
Transition Table Reader GND | Extender Pin: GND |
Wire Ground | Extender Pin: GND |
I installed the Finite State Machine Panel onto the console and proceeded to wire the 33 Hall Effect Sensors to the Arduino.
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Here are the Arduino pins the sensors are connected to:
A1 | A0 | Ab | B1 | B0 | Bb | C1 | C0 | Cb | |
---|---|---|---|---|---|---|---|---|---|
WRITE | 22 | 23 | n/a | 24 | 25 | n/a | 26 | 27 | n/a |
MOVE | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 |
GOTO 1 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 |
GOTO 2 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 10 |
In addition the following connections were made:
From | To |
---|---|
HALT Lamp | Arduino Pin: 11 |
PLAY Button | Arduino Pin: 12 |
RUN/STEP Switch | Arduino Pin: 13 |
Extender Pin: GND | Arduino Pin: GND |
Extender Pin: VCC | Arduino Pin: VCC |
Extender Pin: SCL | Tape's Extender Pin: SCL |
Extender Pin: SDA | Tape's Extender Pin: SDA |
Done Wiring
That's it. The Turing Machine Demonstrator hardware is completed. More testing and a lot of coding are in my immediate future.
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