What is it?

The HMC-20 is a flexible multi purpose, low cost HMI graphical board that is suited to contain an add-on board to extend communication interfaces. The choice for a hardware splitup enables re-usability of the graphical board into multiple end-applications and reduces the cost in term of production quantities. Both boards communicate by means of a real time serial command interpreter, which makes it possible to quick-start creating demo's by implementing a Python script that communicates trough an FTDI-cable, before developing additional hardware.

The solution aims to reduce design complexity by abstracting the graphical part from the application part . The graphical layout can be determined by means of a json file (1) and a range of images (bmp/jpg) that are initially loaded from the SD-flash card into an on-board flash chip. The graphical controller can then read-out the chip directly with DMA (Direct Memory Access) to speedup image loading trough SPI-bus. The memory chip is also used to save internal parameters like a pin code or a user setting.

Why it has been developed?

The market fit is situated between high end Linux-based devices (Beckhoff, Siemens, etc.) and low cost, less-flexible and constrained Asian boards (Nextion, Topway, etc.). It should provide a qualitative and robuust solution with minimal adoption effort to European standards and with in-house supporting and development capabilities.

Because of the generic character of the board, the potential application domain is wide but focusses initially on industrial applications that could benefit from incorporating the HMC-20 board as a hardware part.

What makes it unique?

Button actions are predefined as commands and are defined in the json-file (1). It means that the graphical board also works independently when the interfaces are not the limiting factor. The graphical board has standard 5 digital inputs, 5 digital outputs, a USB-C 2.0 connector with a virtual serial debug interface and a touch matrix connector. There is also a RTC battery and a 24bit TFT RGB connector with touch controller interfaces for capacitive and resistive touch panels. Next to the graphical controller, there is a STM-32U575 processor that is programmed trough an SWD-connector thats connects to a ST-Link V2 programmer. An internal boot loader (1) enables programming over USB without using the programmer.

On the board there is also an auditive piëzo buzzer and a graphical font-chip that contains character maps for more than 150 languages. Additional internal user defined fonts can be generated in the source code. The power supply creates a stable internal 5VDC rail for its internals and the add-on board. A PWM-driver enables backlight dimming in the full range. The I/O voltage range is configurable by jumpers.

A 3D-printed case (2) that fits both boards shows the housing posibilities. The assembly forms a console that could be wall-mounted for applications in buildings, automotive environments or green-houses.

The graphical board comes with demo applications like a fogger, machine interface, home automation interface and automotive signalization module. The demo contains a 1000cd/m² high brightness display that shows automotive or agricultural possibilities where sun-readability and glove-handling is important. The customer can develop his own interface board or use a default add-on board UAB-23 (3) with standard interfaces (Ethernet, CAN, RS-485, Mikrobus) with demo code.

Remarks

(1) These functions are still under development.
Layout is currently hard-coded as isolated source files.
(2) Moulded case has MOQ of 500pcs.
Other form-factors can be custom made.
(3) UAB-23 under development, can be pre-ordered.

More info? Mail to info@saleconix.be