NEMA 17 and A4988 Uno Rev3 overload?

Other Hardware Motors, Mechanics, Power and CNC
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Hello, new to electronics here. I'm building a combined ph monitor + syringe pump setup such the stepper motor (NEMA 17) rotates and adds the syringe solution when measured pH crosses some threshold. I suspect I've blown a voltage regulator in the Arduino's (Uno Rev 3) power supply (NCP1117ST50T3G). However, I'm not sure if it's because the draw of the stepper motor overloaded it or if I happened to accidentally touch some pins together while working on it and caused a short. I've yet to attempt powering up the entire system at once so I wasn't expecting an overload but that doesn't necessarily mean much.

Could I ask for comments/don't-do-that's on the wiring diagram I've attached? This setup is a combination of a few things I found online so I don't have an exact circuit to go off. I thought about using a separate 9V power supply for just the stepper board but went against it, perhaps I should go back to that? Secondary question: if I don't, do I have to program what voltage to output via Vin when using an external power supply? Thanks for any feedback!

Parts are:
Arduino Uno Rev3, External power supply (12V, 2A), 4988 stepper motor driver and shield (9V, 1A), NEMA 17, Gravity analog pH meter and transmitter board (5V), SSD1306 OLED 0.96" (3.3V), and not pictured is a 1602 LCD shield (5V) that plugs directly into the pins of the Arduino which I couldn't figure out how to properly represent on the diagram.

Wiring_Diagram
Wiring_Diagram1231×1368 127 KB

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Welcome to the forum

The biggest don't is don't use the Arduino as a power supply or it will get damages as you have already discovered

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Thanks for your response and welcome. Yes, I'm seeing that, it's fun way to learn.

In this case, if I have a dedicated power supply to the A4988 (connecting to the VMOT and GND pins), would I still need to connect the 5V pin to the Rev 3? Or should that be left empty and only the enable, step, and direction pins be connected?
Edit: nvm I figured that part out

I suppose I'm confused though because the project which I'm basing the motor setup on has it wired just as I do and they don't seem to have any problems with it.

Also, is this a hard rule or is it a general rule with limits? E.g., can I get away with it for low draw devices? Thinking specifically about plugging in the 1602 LCD - using the Arduino as the supply there must be okay seeing as it's made to be directly connected?

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