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 Controls the VFD display of WACCA cabinet from an Arduino.
 
+[example video](https://twitter.com/akasaka_spk/status/1659505635078311936)
+
 ## Schematic
 
-(sorry, no picture)
+![schematic](sch/schematic.png)
 
 Rx,Tx of Arduino Pro Micro -> MAX232 -> Tx,Rx of VFD display (COM2 cable on WACCA cabinet)
 
+Pin 2 of Arduino -> Coin selector (N-O contact)
+
+Gnd of Arduino -> Coin selector (COM contact)
+
 For other connections around MAX232 see tutorials online such as the one in [DIYODE Magazine](https://diyodemag.com/education/the_classroom_rs232_the_max232_ic_arduino_uno).
 
 For RS232 pinout see e.g. [PinoutGuide](https://pinoutguide.com/SerialPorts/Serial9_pinout.shtml)
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