ESP8266/Serial Debugging

Debugging the serial connection to the ESP8266

Experiments

Variables and Parameters

I had to try a couple of combinations of different parameters.

Variables:

• Baudrate - 57600 or 115200 (depending on chip/board version)
• RX/TX pinouts
• High/floating CH_PD pin

First Set of Experiments

With this first set of experiments, I was connecting to the serial device at /dev/tty.usbserial.

Connecting to serial port at /dev/tty.usbserial with timeout of 5 seconds:

First Round

First round (slow rate, v 1):

Test 1A: 57600 baud rate, RX on ESP8266 connected to TX on PL2302 (mini usb to serial board), CH_PD pin floating

• Nope.

Test 2A: 57600 baud rate, RX on ESP8266 connected to TX on PL2302 (mini usb to serial board), CH_PD pin high

• Nope.

Test 3A: 57600 baud rate, RX on ESP8266 connected to RX on PL2302 (mini usb to serial board), CH_PD pin floating

• Nope.

Test 4A: 57600 baud rate, RX on ESP8266 connected to RX on PL2302 (mini usb to serial board), CH_PD pin high

• Nope.

Second Round

Second round (fast rate, v 2):

Test 1B: 115200 baud rate, RX on ESP8266 connected to TX on PL2302 (mini usb to serial board), CH_PD pin floating

• Nope.

Test 2B: 115200 baud rate, RX on ESP8266 connected to TX on PL2302 (mini usb to serial board), CH_PD pin high

• Nope.

Test 3B: 115200 baud rate, RX on ESP8266 connected to RX on PL2302 (mini usb to serial board), CH_PD pin floating

• Nope.

Test 4B: 115200 baud rate, RX on ESP8266 connected to RX on PL2302 (mini usb to serial board), CH_PD pin high

• Nope.

Second Set of Experiments

Keep on trying. I ran the serial library's port discovery tool, and it listed /dev/cu.usbserial, so maybe that's the device we should be using:

$ python -m serial.tools.list_ports
/dev/cu.Bluetooth-Incoming-Port
/dev/cu.usbserial
2 ports found

First Set of Experiments

Connecting to serial port at /dev/cu.usbserial with timeout of 5 seconds:

Test 1A: 57600 baud rate, RX on ESP8266 connected to TX on PL2302 (mini usb to serial board), CH_PD pin floating

• Nope.

Test 2A: 57600 baud rate, RX on ESP8266 connected to TX on PL2302 (mini usb to serial board), CH_PD pin high

• Nope.

Test 3A: 57600 baud rate, RX on ESP8266 connected to RX on PL2302 (mini usb to serial board), CH_PD pin floating

Test 4A: 57600 baud rate, RX on ESP8266 connected to RX on PL2302 (mini usb to serial board), CH_PD pin high

Second Set of Experiments

Second round (fast rate, v 2):

Test 1B: 115200 baud rate, RX on ESP8266 connected to TX on PL2302 (mini usb to serial board), CH_PD pin floating

Test 2B: 115200 baud rate, RX on ESP8266 connected to TX on PL2302 (mini usb to serial board), CH_PD pin high

Test 3B: 115200 baud rate, RX on ESP8266 connected to RX on PL2302 (mini usb to serial board), CH_PD pin floating

Test 4B: 115200 baud rate, RX on ESP8266 connected to RX on PL2302 (mini usb to serial board), CH_PD pin high

Attempt Number 2

Okay, let's start over.

Installing the esp8266/arduino library from Github makes it possible to program the ESP8266 microcontroller directly from the Arduino IDE, and provides some nice API functions as well. It takes a couple of steps to install, but the steps are dead simple.

Preparing Arduino to Work with ESP8266

Start by installing the necessary packages to program the ESP8266 directly from the Arduino IDE. This will require Arduino version 1.6.8 or later.

Download the ESP8266 Arduino repository here: https://github.com/esp8266/Arduino

Next, install using the Arduino Boards Manager. Open the Arduino IDE, and click Arduino > Preferences. In the "Additional Board Manager URLs" field, enter the following URL: http://arduino.esp8266.com/stable/package_esp8266com_index.json

Go to Tools > Board > Boards Manager and do a search for the term "ESP." This should pull up the ESP board, and you should see a button that says "Install."

Manual Programming

To set the ESP8266 up for manual programming (whatever that means...), we can arrange the circuit as follows:

http://reflowster.com/blog/2015/05/11/esp8266.html

Attempt Number 3

This is straight up STUPID. Is it really the case that no single person can adequately explain their circuitry? I am seeing diagrams with resistors with no ratings, circuits that make absolutely no sense, firmware files that do not exist, hand-wavey comments like "use your favorite tool to flash the firmware of the ESP8266" without a single mention of a single such tool.

This is a chip with a lot of potential, but a lot of documentation about it is just absolute garbage. Getting tired of the runaround.