Smart Assistive Cash Drawer

by zhouvp in Circuits > Microcontrollers

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Smart Assistive Cash Drawer

截屏2021-12-02 下午3.36.56.png

This project creates an hardware interface for the cash drawer with RJ12 connector. The interface is powered by a 24v DC power source. With a microcontroller and relay module, the cash drawer can be controlled by a customizable switch (which is also quick swappable for different needs). The builtin speaker module/port also provides audio feedback when opening the drawer. As well as a 3 pin JST connector that powers a 8x32 matrix display.

Supplies

  • 24v DC power supply
  • DC connector
  • 5v relay module
  • 24v to 5v step down module
  • 8x32 LED matrix grid
  • Mini Speaker
  • 3.5mm audio connector (female)
  • Circuit Playground Bluefruit (microcontroller)
  • Cash drawer with RJ12 Interface
  • Cardboard
  • Ice-cream sticks
  • Glue Gun
  • Wire
  • Tape

The Design

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This is the basic idea behind the design, major component listed

Reference Material

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this is the interface for the cash drawer connector, we will need to use the two wires labeled "coils" to trigger the drawer lock

Schematic Design

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Follow this design step to put together the control interface

Connection

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Connect all components as described above, use ice-cream sticks as needed to reinforce the connectors. Hot glue or tapes to secure the parts.

Add Magnets

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Finish the enclosure, and tape some magnets for easy attach and detach from the drawer.

Program the Board

Upload the code.py program to the circuit playground Bluefruit, and also download the audio files to the board

Finished!

Give your control interface a nice looking color with the cardboard, and connect the RJ12 connector to the drawer, power everything on, and see it working!