X27 Stepper Gauge PWM ATtiny85

Direct fit for a 1966 Chevy C10 Cluster.

Side Note: the imagine shows a full-size ATtiny85 but the Gerber file here has the smd version, send me a email if you want the full side version Gerber file

Board to control an x27 motor using an LS PCM signal

Input 12-30v and outputs 5v for the ATtiny85 that controls the motor

Input for the PWM needs to be around 12-16 volts, this will be lowered to 5v(or less) for the ATtiny to read.

X27 stepper motor is to be mounted on the back for better clearance, the circuit is on the front side.

Pretty easy setup, solder all the parts, and program using the headers(right side of the pcb) and an Arduino UNO as an ISP, and boom, it's ready to go.

I programmed the tiny85 using this guide HERE, the pin headers are organized in the same way. starting with Pin 1 and going to Vcc on the Tiny85.

on the left-hand side where the terminal connector is 1st pin is Car battery power, 2nd is car ground, 3rd is the VSS pwm signal from the PCM.

My current code is on GitHub and is almost set up for an ls swap Speedo. (Currently, it's an older version I created to set up for a 1966 C10

Speedo Gauge with rough estimates)

https://github.com/joeyjoey1234/Ardunio---x27-Stepper-Speedo-Gauge---LS-Swap

The code will need to be adjusted for its needle starting point and degrees moved per MPH.

Code can be reconstructed for RPM etc., just take my program as an example for steps, etc.

The area for pin headers on the bottom right for reprogramming the ATTiny85 to your liking or you can preprogram and not solder a header