Hello to you all, While surfing on Internet, I came across the masterpiece A MILLION TIMES AMT72 by HUMAN SINCE 1982 and was immediately seduced. Today, I'm trying to reproduce this masterpiece, and as I'm not very well versed in electronics, I'd like to know, with your help, if my editing is “electronically” correct. OPERATING PRINCIPLE 1 master module with an ARDUINO MEGA 2560 (chosen because of the I2C internal pull-up resistors) 18 slave modules, each with an ARDUINO NANO, 2 AX1201728SG drivers, 8 DRV5032 hall effect sensors and 4 BKA30D-R5 biaxial motors. The master controls the slaves via I2C. Here you have the block diagram [Blocks] and here the wiring diagram [SLAVE MODUL] [MASTER MODUL] Thank you for your feedback.

[image] barbess: chosen because of the I2C internal pull-up resistors) Good but the number of slaves possible to use is not unlimited anyway. [image] barbess: 18 slave modules, each with an ARDUINO NANO That likely calls for additional pullups. Read datasheets and their data regarding the I2C lines..

Thank you Railroader for the feedback [Capture d'écran 2025-08-27 224605]

[image] barbess: ARDUINO MEGA 2560 (chosen because of the I2C internal pull-up resistors) This sounds weird to me. The Mega 2560 chip does AFAIK not have internal I2C pull up. A Mega board has therefore physical set of 10k resistors added. Multiple processors to control a bunch of stepper motors is a common beginner's mistake. One processor with port expanders (shift registers) is a better solution. I have posted a project on this site controlling 48 stepper motors with a single Classic Nano. The limit with that board was about 150 motors (at full speed). Did you search for the prices of commercial units. Be prepaired to sink the price of a small car in a project like that. Leo..

[image] Wawa: I have posted a project on this site controlling 48 stepper motors with a single Classic Nano. The limit with that board was about 150 motors (at full speed). Could you please send the link to the project Thanks

[image] barbess: Thank you Thank You! Not providing any exact recommendation for Your project general knowledge of using a bus, like I2C, You aim for a maximum I2C project. One important part is the lenght of the I2C bus cables. It’s designed for rather short cable lengths.

Note that A6 on a Nano is analogRead only and has no internal pull up. The Rx pin of the ESP8266 could be damaged by the 5volt-logic of the Mega. It should include a 1k:2k2 resistor level shifter. Leo..

[image] Wawa: Be prepaired to sink the price of a small car in a project like that. The artworks being imitated sell for USD 100K-200K.

BKA30D-R5 biaxial motors. Are driven like the X27 automotive gauge steppers, and require a special pulse sequence for accurate positioning. What is your plan to produce that pulse sequence? An 8 pin ATtiny would suffice as a driver for one X27 gauge motor but 8 pins are required for the four motor coils on the biaxial stepper.

A library is available for those 6-step sequence motors. The writer didn't think of adding an option to drive shift registers. If modified for that, then a 74HC595 could drive one of those dual-shaft motors. A single Nano could drive a whole train of shift registers. No other parts needed. OP's current plan adds too much complexity. Upscaling is not as easy as OP might think. Leo..

Replica of the AMT72 by Human Since 1982

Projects General Guidance

Wawa August 27, 2025, 9:39pm 7

It all began here (click).
@ba47 made a variation of it.
Also see the Sparkfun ClockClock project.
Leo..

Topic		Replies	Views
Controlling 32 or more stepper motors Motors, Mechanics, Power and CNC	108	2424	November 6, 2024
X27 stepper driver General Guidance	17	772	August 31, 2025
PCA9685, Arduino nano and 16 pairs of motors General Guidance	72	1006	February 15, 2026
Suche Servomotor Treiber Platine 4x bis 8x Deutsch	20	573	December 10, 2025
My nema 17 motor isnt working with my a4988 and esp32 Motors, Mechanics, Power and CNC	64	1357	June 12, 2026

Replica of the AMT72 by Human Since 1982

Related topics