Raspberry Pi 4B GPIO extensions and HAT

Comprehensive control units for robotics projects

Kiedy tworzymy projekt robota, dobrze jest zadbać o jego dobre wyposażenie pod kątem układów sterowania. Znakomitym solution jest nakładka 4tronix RoboHAT. Ten moduł zawiera zestaw programowalnych wejść i wyjść, to których możesz podłączyć czujniki, buzzers, LEDs oraz sterownik silników elektrycznych i serwomechanizmów. Nakładka została starannie zmontowana i jest gotowa do podłączenia do Raspberry Pi bezpośrednio po unboxing. Zasilanie modułu może być podłączone poprzez złącze śrubowe ARK oraz gniazdo zasilające DC jack. Konstruktorzy udostępnili przykładowe programy i zestawy instrukcji w Pythonie, w oparciu o które użytkownik może poznać zasadę działania robotów. Z tego powodu, nakładkę RobotHAT szczególnie polecamy osobom rozpoczynającym przygodę z robotyką.

An interesting offer for music and electronics enthusiasts

Using the Pimoroni Piano HAT overlay, you can turn the Raspberry Pi 4B into a simple music synthesizer with keyboard and buttons. According to the standards in the hardware design of synthesizers and drum machines since the 1980s, this overlay supports MIDI protocol (Musical Instruments Digital Interface). The keyboard contains a single octave with a C1-C2 tonal range (13 notes). These are capacitive touch keys. In addition, the user has at his disposal buttons for changing the tonal range (Octave Up / Octave Down) and a button for selecting sound presets stored in memory. The Piano HAT overlay is equipped with a GPIO connector that is compatible with the Raspberry Pi 4B minicomputer hardware. A practical feature of the overlay is built-in LEDs that perform an educational function. All you have to do is follow which of the LEDs that are linked with keys are lights up to learn to play simple songs from scratch. The program implementing this function was written in Python and is pre-loaded into memory in the Piano HAT module. The alternative,,non-musical” project, which you can create by using this board is a whac-a-mole game.

A simple way to control electrical circuits powered by mains voltage

Also, SparkFun Electronics has prepared interesting hardware extensions for Raspberry Pi. The RELAYplate module contains seven Single-Pole Single-Throw Normally Opened electromechanical relays. With this overlay, you can control the circuits powered by a voltage of 120VAC or 30VDC. The overlay allows you to switch-on and switch-off the power supply of electric motors, pumps, fans, lighting, heaters and other electrical devices. The kit includes a protective cover to prevent accidental electric shock due to contact with high voltage circuits. At the same time, you can connect eight such modules together, which gives you the ability to control up to 56 circuits in parallel, independently of each other. The board is equipped with LEDs that indicate the state of contacts of individual relays. The RelayPLATE overlay is controlled by a 40-pin GPIO connector, the pin layout of which is compatible with most models of the Raspberry Pi minicomputer, including Pi 4B.