C, C++ developer required to write control and telemetry software based on ESP32 or STM32 microcontroller.
1. The device must connect to the vending machine using the MDB version 4.2 protocol in SLAVE mode and present itself as a bank card reader.
2. The device must connect to the bank payment terminal using the MDB version 4.2 protocol in the MASTER mode, and present itself as a vending machine.
3. An example of the operation of the device:
- the vending machine makes a payment request to the device
- the device, depending on the business logic, makes a request for payment to the payment terminal or immediately responds to the vending machine with a refusal.
- if there was a request for payment to the terminal, the device waits for a response and, depending on the business logic, responds to the vending machine with confirmation or refusal.
You also need to implement the ability to make a request for a refund to the client.
for testing business logic, you can put it in a yuart terminal for a PC or on a GPIO button.
you can use Arduino or PlatformIO