Request for Guidance on Custom Motherboard Integration with Marlin Firmware

Dear Esteemed Marlin Development Team,

I hope this email finds you well. First and foremost, I would like to extend my heartfelt gratitude to the Marlin development team for your tireless efforts and the incredible work you have done. Your contributions to the 3D printing community have been exceptional, and I hold the Marlin Firmware in the highest regard.

I am reaching out to seek your guidance and assistance in a matter that I am extremely enthusiastic about. I am in the process of building a custom motherboard using the Arduino 2560 microcontroller and aim to integrate it with Marlin Firmware.

My objective is to create a personalized motherboard, and I'm eager to understand which specific files and configurations I need to include within the Marlin firmware to achieve this. Your expertise and direction are invaluable to me, and I believe that your insights will empower me to successfully add my custom motherboard to Marlin.

I appreciate the hard work and dedication that the Marlin Development Team has put into this open-source project. Your guidance will not only benefit my personal project but also contribute to the larger community. I am confident that with your assistance, I can make a valuable addition to the Marlin ecosystem.

Thank you for your time, consideration, and the remarkable work you do. I eagerly anticipate your response and am sincerely grateful for any insights and support you can provide.

Warmest regards,

Mahdi
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Edited 1 time(s). Last edit at 10/12/2023 03:08AM by VDX.

Stop publishing your e-mail address. the only one who is going to use it are spammers, who scrape the internet for any e-mail address they can find to send spam to!


Every board needs a MOTHERBOARD name you define it in Marlin/src/core/boards.h, the number and name just needs to unique, the name starts with BOARD_ , you should put yours with the other ramps boards


The new board requires a pins.h file to tell marlin what pins are used for what feature. This is added to Marlin/src/pins/pins.h

eg

#elif MB(YOUR_MOTHERBOARD)    //   Note the BOARD_ prefix is omitted here.
  #include "ramps/pins_for_your_your_board.h"            // ATmega2560              env:mega2560

Note the comment is actually used. The entries with a env: are the valid build environments usable for your board.

Look at existing pins_{BOARD}.h file for examples of the expected keywords.

Note the mega2560 is deceptively simple...

For marlin need to use Arduino standard pin definitions [docs.arduino.cc]

Hardware UARTs are fixed, so make sure you don't accidentally use the required IO pins for something else.
Especially UART 0 which is required for firmware updates

PWM and analog pins are similarly locked.

If your planning to use software serial for tmc uart communications, , only pins that support the level change interrupt feature can be used as RX pins.

If you using extended DIGITAL pins 70-85, you need to use env:mega2560ext instead of env:mega2560 to support the extra pins

Edited 2 time(s). Last edit at 10/12/2023 03:36AM by Dust.

Thanks again, dear Marlin development team. You're invaluable!