jerome arul

makes (almost) anything

networking and communications

connect to the internets

ESP32 datasheet
• connect to wifi or ble
• quick pin-out design

neil's ESP32-WROOM board
add Library to arduino
File > Preferences
add this to "Additional Board Manager URLs"

Tools > Board > Boards Manager
search for "ESP32 by espressif", install.

design the board

esp32 schematic - pinout is little nuts

esp32 layout

pin-out front
pin 18 > SD3
pin 19 > CMD
pin 20 > CLK
pin 21 > SD0
pin 22 > SD1
pin 23 > IO15

pin-out right
pin 26 > IO4
pin 27 > IO16
pin 28 > IO17
pin 29 > IO5
pin 30 > IO18
pin 31 > IO19

pin-out left
pin 9 > IO33
pin 10 > IO25
pin 11 > IO26
pin 12 > IO27
pin 13 > IO14
pin 14 > IO12

esp32-WROOM pins

esp32 traces

esp32 outline + holes

the board

soldered - plugged in

solder paste and reflowed with heat gun on
• esp32 chip
• tactile button


initially finds port (ftdi cable)

timed-out error

timed-out error v3.0-dev
Serial port /dev/cu.usbserial-ABSCDHIN

A fatal error occurred: Failed to connect to ESP32: Timed out waiting for packet header

apparently this error has something to do with the BOOT button. port disappears after i plug in board, error message changes

vcc pin gets hot, regulator gets hot

realized button resistor is not connected to EN.
soldered a jumper

still hot, port disappears


sneaky trace under resistor

did some torubleshooting with anthony
desoldered a couple of capacitors at EECS
found a short under the button
some trace needed extra love

did serial test first
wifi scan sketch under Examples>ESP32

found the EECS wifi network!