Smart Assistive Cash Drawer

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.

• 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

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

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

Follow this design step to put together the control interface

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

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

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

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!