We are looking for a specialist to implement automatic data exchange with a POS system that does not have an API

The goal of the project is to create two devices that will communicate with each other via cable (485). 1) The first device is a metal casing with connectors, it is a switching block with 16 relays + Ebyte-400M2213S which will check for the presence of a signal at specified frequencies. 2) This is a control panel on esp32 mcu2.8 smart display. Its purpose is to control the load and receive data from the switching block about the presence of a signal at specified frequencies. A specialist or specialists are needed who have experience in such work. Circuit design and programming. All technical resources will be provided. We discuss the project, possible changes, etc... and we work.

Development of a Flight Controller for Fixed-Wing UAVs An experienced Embedded Hardware Engineer is needed to develop a flight controller for fixed-wing UAVs. Tasks: develop the electrical schematic; design a multilayer PCB; select the component base; prepare Gerber, BOM, and Pick&Place for mass production. Main requirements: microcontroller STM32H743 or equivalent class; functionality similar to Matek H743-Wing V3 (without copying); compatibility with PX4 or ArduPilot; interfaces: CAN, UART, SPI, I2C, USB, PWM; support for connecting GPS, IMU, barometer, telemetry, and other peripherals; maximum use of components that meet NDAA requirements (without using Chinese components where possible). Mandatory when responding: describe your experience in developing Flight Controllers or other Embedded platforms; provide examples of completed projects; indicate which CAD systems you use (Altium, KiCad, etc.); specify estimated timelines and costs for completion. Preference will be given to contractors with experience in developing electronics for UAVs, robotics, or avionics.

There is a board with esp32, sim800l, mini 560pro 5v. It has two pulse inputs (coin, bill). 1. A 6-pin connector (mdb) needs to be made. 2. Integrate power into the board, it can be replaced with ti, Pololu D24V5F3 6-30V 3.3V / 1.5A, as a choice or integrate the existing module into the board. 3. Replace sim 800l with another module (the pins fit, but differ in places). Gerber files are available, there are no schematics, base jlpcb.

I have some logic in Google Excel related to the integration with the Nova Poshta API and the Turbosms API. Overall, everything works fine, but some functionality needs to be added. All details will be discussed in correspondence. I will provide access to the Excel and the code. It is essential for the performer to have experience working with Google Excel JS in Apps Script.