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7-segment display and STM32 using ChibiOS

7-segment display and STM32 using ChibiOS

We have already introduced MAX7219 in STM32, ChibiOS and a 8×8 LED Matrix, so we are going to jump directly to code section. For convenience we just report link to documentation:

MAX7219 Datasheet

Note that even if pins are arranged in a different way, pin-out remains the same of the 8×8 LED matrix.

In this demo we are going to use Code-B decode to write with ease some number on our 8 digit 7-segment display.

In the demo shown in the video above we set up MAX7219 as normal operation mode, Code-B decode mode for each digit, scanning the whole display with the maximum continue reading...

STM32, ChibiOS and a 8×8 LED Matrix

STM32, ChibiOS and 8x8 LED Matrix

The MAX7219 is a compact, serial input/parallel output common-cathode display driver. Included on-chip there are a BCD code-B decoder, the multiplex scan circuitry, segment and digit drivers, and an 8×8 static RAM that stores each digit. Only one external resistor is required to set the segments current.

This chip is often used to drive 7-segment display having up to 8 digits or up to 64 individual LEDs. It is not unusual find this chip in DIY kits to be mounted on a small PCBs like that used in this article (See Fig. 1).

This chip could be found in different packages continue reading...