FreeModbusTool A free tool for modbus for serial(rtu&ascii) and eth ports. unit1- web serial tool References Antecer's Honoka55's https://blog.spacehuhn.com/serial-terminal https://www.frederickscompany.com/web-serial-terminal/?srsltid=AfmBOoruGKJD4N_dumCzHxBprFHKUjVcz1ZwuqhDRwHM__JApivRkYf2 Web Serial ESPTool: https://learn.adafruit.com/adafruit-magtag/web-serial-esptool