Wiring Guide

Following you can find useful references for the hardware setup such as schematics and example breadboard wiring setups.

ESP01 Pinout:

FTDI Wire Guide:

connect FTDI cable
- black:GND, brown:CTS, red:VCC, orange:TXD, yellow:RXD, green:RTS

Breadboard Wiring Guide:

Note:

3.3v (red/purple)
gnd (brown - rightmost)
reset btn (brown centered)
flash btn (gray) Modes:
normal operation (btns released)
reset (left btn pressed)
flash (both pressed, left (brown) released first then right (gray))

Example breadboard setup with two buttons:

And a more neat version produced by Robin Baran (@RBinsonB)

Debug serial interface

Connect ftdi cable with (vcc, gnd, ch_pd, tx(esp) -> rx(ftdi-yellow))
- in terminal execute sudo screen /dev/ttyUSB0 115200 8N1

Common Problems

if device is busy use lsof | grep /dev/ttyUSB0 (for USB0) and shutdown the occupying process
- Often QGroundControl is the culprit.

References

Flash procedure wiring instructions
Official PX4 ESP8266 documentation
Configured to connect to a fixed hotspot (see section Usage)
esp8266 runs on /dev/ttyS0 on pixracer configuration with 20000 B/s (baudrate of 921600)
- see px/boards/px4/fmuv4/init/rc.board_mavlink
inspired from dogmaphobic's work.
depends on esp8266wifi (Documentation).
- e.g. see IP class
- e.g. see WiFi header
- e.g. see UDP driver

Preparation of PX4

flashing px4_fmu-v4 - install arm-none-eabi-gcc here. - in this repository root execute pip install -r requirements - in px4 firmware folder make px4_fmu-v4 upload

Connect to the Device

connect via mavros (installation instructions)
- roslaunch mavros px4.launch fcu_url:=udp://:[email protected]:14555
- test it with rostopic echo /mavros/rc/in (shows rc commands send to the aerial vehicle)