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A workbench full of RP2040, AVR, I²C and SPI modules

Summary

Johannes presents his winter selection of microcontrollers, displays, RFID, CAN, storage and interface modules. Among others, RP2040, ATmega328, ATtiny85 and ATmega32U4 are named. An MCP2515 module adds CAN bus support.

Ideas

  • I²C connects many slow modules over two signal lines.
  • SPI suits faster displays, memory and CAN controllers.
  • MicroPython and the REPL allow interactive hardware experiments on the RP2040.

Insights

  • A varied collection of modules only becomes productive through small, repeatable test programs.
  • Interactive runtimes shorten the path between measurement, hypothesis and change.

Facts

  • The OLED displays use SSD1306 controllers.

Recommendations

  • Keep a tested minimal test including the pinout for every module.
  • Visibly separate 3.3 volt and 5 volt components and use level shifters.

References

Read the original article on hanez.org

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