Use a potentiometer to control redstone

This is the reverse of the LED experiment: Arduino A0 → USB serial → SerialCraft → redstone.

Wire a low-voltage potentiometer with its outer terminals to 5 V and GND of an Arduino Uno R3 and its wiper to A0. The Uno's ADC normally reads 0–1023; map it to the SerialCraft protocol's 0–255 range.

int reading = analogRead(A0);
int value = map(reading, 0, 1023, 0, 255);
Serial.print("pot_val:");
Serial.println(constrain(value, 0, 255));

This snippet illustrates the format only. In real firmware, send the initial sample including zero, meaningful changes and a periodic snapshot and limit the sample rate instead of transmitting as fast as loop() can run.

In Minecraft, open Boards → Configuration, set the Channel to pot_val, choose Hardware → Minecraft and ANALOG. Then in the world use Shift + right-click on a terminal to set a red output face. Connect redstone dust to that face. A value around 128 should give approximately 8 redstone strength; 255 should give 15.

If you see only on/off, check whether the block is DIGITAL. If nothing changes, verify the exact channel string, newline, serial baud rate and face direction.

Continue with the official examples and signal conversion reference.

An ESP32 typically uses 3.3 V GPIO levels; never feed 5 V directly to an ESP32 GPIO.