Boss is to old school and wants a portable programmer

[username]

So I have a project with a new company. I Incorporated 3 ways to update the firmware. USB, OTA & uSD. Made the PCB and everything worked prefect. In our last meeting the Boss looks at the board and says " where does the programmer plug in at? How is the customer going to update the firmware? " To which I tell him the 3 ways they can do it. The boss is 78 years old and says I don't want any of the modern stuff for people to hack into. I want a portable programmer that we will ship the customer for them to plug in.

I was beside myself with how outdated his is. SOOOooooo.... I have to build a portable programmer. My first though was just to connect the uSD card lines to say a RJ48 connector, and in my box just put another RJ48 connected to a uSD card socket, and use the spare few wires for a green/red led to let them know its flashed. BUT in another meeting they wanted to add more stuff so I needed the IO that I was using for the uSD card. So I am left with serial programming.

Talked allot here, but you hopefully get the corner I am in. My question is there a document that talks about the serial programming methodology. My idea is to take another ESP32 with a uSD card, and put the bin file on it, and have it act like the PC to program the other ESP32 via serially.

[ESP_Sprite]

You probably want to take a look at this.

[username]

Prefect! Thank you so much!