ESP8266 Successor – ESP32 released with CAN support 

​o, the interesting little ESP8266 WiFi SoC finally has a younger brother which appears to be even more capable. Among other interesting updates, the 32 bit Dual Core microcontroller still supports WiFi, but also Bluetooth Low Energy, a DAC, many more ADCs, GPIO pins, etc. etc. Lots of good details here: 

The ESP32 is now avaialble to buy directly as a chip, or on small development boards. Unfortunately however, everywhere is currently sold out, so it will be a while before I get one.

The feature which particularly piqued my interest, however was the mention of CAN 2.0 support. I have already used the ESP8266 in combination with an MCP2515 to create a CAN to Wifi gateway, but if the ESP32 supports CAN on board, then this could potentially lead to a single chip solution. 

There are already a number of other microcontroller which do offer CAN bus support (actually the list is probably huge since nearly all automotive and industrial spec controllers will) but for example the Arduio Due (Atmel SAM3X8E ARM Cortex- M3 CPU)  and the Teensy development boards support CAN. 

However, most lf these chips simply support the CAN data link later rather than the physical layer, and so still require a CAN transceiver to do the voltage conversion to CAN compatible physical voltage levels. To be honest, I expect the ESP32 to require the same, although it would be great if it was on board.

So far i haven’t managed to find any now details on the cab bus interface. I have read through the data sheets for the chip, but they only mention the CAN support in one line and as a single block on the system block diagram.

This forum thread sheds slightly more information onto the situation with a response from Rudi of expressif regarding the integration of the CAN connections. He sends to suggest that the can will be suggested through normal GPIO pins which would suggest that they might not be compatible with the higher voltage that CAN bus physical layer typically requires.

ESP8266 CAN Bus with MCP2515

I have just bought another ESP8266/NodeMCU development board cheapy from eBay (this one) with an ESP-12E chip on board. I’ve also bought an SPI-CAN bus interface with the common Microchip MCP2515 CAN controller to try and create a CAN-Wifi gateway.

The pinout for the ESP-12E NodeMCU board is apparently as below:
ESP-12E NodeMCU Pinout

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3SGTE Mk2 MR2 Turbo Lambda/Oxygen Sensor Part Number

I had real trouble finding a suitable alternative oxygen/lambda probe for my 1992 Rev 2 MR2 Turbo. I can’t find the original Denso part number at the moment, but I managed to find that a Denso DOX-0107 fits the flange size correctly and is 1-wire, it just requires soldering to the original connector. It’s got a Flange 44 type flange which apparently matches the 3SGTE.

I got it from

Duke Axial Engine

So a friend told me about the Duke Axial Engine the other day. It’s certainly a very interested idea and does produce some clever solutions to some of the fundamental complexities and disadvantages to the reciprocating internal combustion engine. I always like the idea of novel engine designs, and this one certainly looks like it has potential. Take a look at the video followed by some analysis after the break.

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ESP8266 Lua DHT11 Temperature and Humidity Sensor

After receiving my ESP8266 Development/breakout board I have been attempting to create a WiFi enabled thermostat to control my central heating from my mobile phone and give me a means of timer programming my central heating. To be a true thermostat requires a temperature sensor. The ESP8266 board came with a DHT11 sensor and already has pins directly compatible with one. I therefore just required the software to interface with it.

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ESP8266 Useful Links

ESP8266 Flasher Tool:

Latest nodeMCU firmware: LuaLoader for NodeMCU files and ESP8266 configuration:

Simple ESP8266 GPIO Websserver:

ESP 8266 Development Board Schematic:

Write up of the ESP8266 Development Board: