Arduino IL Drive Sim read good write bad

[J-F Garnier]

(04-27-2023 05:52 AM)ThomasF Wrote:  Using the description from Tobie I use the PIL-BOX for my Arduino (or rather the Wemos D1 Mini with ESP8266 for WiFi connectivity).
This is done without any modifications to the PIL-BOX (apart from adding some pins for easy attachment of the ESP) so I can still just attach the USB-cable for normal PC usage if I want to.

Connecting both the ESP and the USB on the same serial lines creates a electrical conflict on the Tx line (towards the PIL-Box IC) - the strongest wins.
I would recommend to insert a e.g. 10k resistor in the Tx line from the USB, so the ESP will take precedence softly, and if not present the USB will still operate.

PIC (Rx)--------/\/\/\/\/----- USB (Tx)
                 |
                  ---------------- ESP (Tx)

J-F