Control system for Hornby points
|
Key Train
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Components
|
|
| Connections
|
MUX 1
CD74HC4067
___________________
|
|
C0 | 1 24 | VCC
C1 | 2 23 | S3
C2 | 3 22 | S2
C3 | 4 21 | S1
C4 | 5 20 | S0
INH | 6 19 | C15
C5 | 7 18 | C14
C6 | 8 17 | C13
C7 | 9 16 | C12
C8 | 10 15 | C11
C9 | 11 14 | COM
GND | 12 13 | C10
|___________________|
Raspberry Pi Pin Raspberry Pi
GPIO CD74HC4067 MUX
1 CD74HC4067 MUX 2
Pin
11
GPIO 17 ----------- Pin 23 (S0) ----------- Pin 23 (S0)
Pin
13
GPIO 27 ----------- Pin 24 (S1) ----------- Pin 24 (S1)
Pin
15
GPIO 22 ----------- Pin 25 (S2) ----------- Pin 25 (S2)
Pin
29
GPIO 5 ----------- Pin 26 (S3) ----------- Pin 26 (S3)
Pin
31
GPIO 6 ----------- Pin 6
(INH)
(Enable for MUX 1)
Pin
33
GPIO 13
-----------
Pin 6 (INH) (Enable for MUX 2)
Pin
7
GPIO 4 ----------- Pin 1 (COM) ---------- Pin 1 (COM)
Pin 1
(3.3V)
3.3V ----------- Pin 16 (VCC) --------- Pin 16
(VCC)
Pin 6
(GND)
GND ---------- Pin 8 (GND)
--------- Pin 8 (GND)
|
Overview
|
 Click track layout to see prototype in action
Click photo to see more
(Chatanooga Choo Choo)
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Final Tablet app
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Final tablet app
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Spectacular drawing failure by ChatGPT
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Chip pin layout generated by ChatGPT
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