Add submission # 6857

#6857

Author: ArduinoBot

registry.txt

@@ -8327,3 +8327,4 @@ https://github.com/NitrofMtl/DUE-ModbusDMA.git|Contributed|DUE-ModbusDMA
 https://github.com/rahulstva/RS_ThingSpeak.git|Contributed|RS_ThingSpeak
 https://github.com/7semi-solutions/7Semi-ADXL335-Analog-Accelerometer-Module-Arduino-Library.git|Contributed|7Semi ADXL335 Accelerometer
 https://github.com/abdullahtemel97/testfirmware.git|Contributed|miniGo
+https://github.com/littlemanbuilds/ESP32_MCPWM.git|Contributed|ESP32_MCPWM