I ordered an ESP32 module from Ebay:
I’ve been writing some software for a Wifi based CAN data logger for the ESP8266 in the Arduino platform, and have been getting a bit of a strange error. It appeared to be related to using the std::string functions in my code – and although I have used this in other sketches without issue, I suddenly received the following error as soon as I simply declared a std::string variable:
c:/users/scott/appdata/local/arduino15/packages/esp8266/tools/xtensa-lx106-elf-gcc/1.20.0-26-gb404fb9-2/bin/../lib/gcc/xtensa-lx106-elf/4.8.2/../../../../xtensa-lx106-elf/bin/ld.exe: C:\Users\Scott\AppData\Local\Temp\build525647f6f8500d071cfab5cccf314276.tmp/ESPCANLogger.ino.elf section `.text' will not fit in region `iram1_0_seg'
collect2.exe: error: ld returned 1 exit status
See how to fix it after the break.
For my own future reference more than anything else, to get the ILI9341 (either Adafruit or otherwise) working on the ESP8266 using the Arduino development environment isn’t completely straightforward. I knew I had this working previously, but couldn’t find the info again, so am copying it here.
See the details after the break.
I dont see a lot of information on personal blogs/diy projects regarding the use of Visual Programming Languages, but this is what I use in my current role as a Control System Engineer developing engine control and test systems. I actually call them graphical programming languages, so if I use the terms interchangably here then I’m actually talking about the same thing. We use visual programming languages for engine ECU control code and Test Cell control code (Simulink + Stateflow and Labview respectively). I believe graphical programming languages are pretty widely used in the automotive industry, and appear to have massive buy in from plenty of other industries too. I think its easy to see why.
So, the interesting little ESP8266 WiFi SoC finally has a younger brother which appears to be even more capable. Among other expansive 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: http://esp32.net/
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.
Warning: do not connect the DHT11 temperature sensor as indicated in the eBay pictures, it is the wrong way around and will fry your board!
Update: Board has arrived, more details and pinout here
It would seem that the ESP8266 is quickly becoming a pretty well supported WiFI microcontroller within the DIY/hacker community, and certainly presents itself as a pretty good alternative to an Arduino for projects requiring simple IO and WiFi. There’s even a project looking at using compiling the Arduino IDE and compatible code for the ESP8266!
I have one of the original versions of these units, but ave struggled to get anything sensible out of it, and so was looking on Ebay for some more items and came across this breakout/development board. For £9.99 I thought I’d give it a go, and ordered it a couple of weeks ago. Will give more details when it arrives. More details and pics after the break
I was sent a link to this website by the author, who appears to have created an Arduino ECU for spark control. Although the details are a little sparse, It appears that he has developed a lot of the required hardware himself. It looks like the main controller is an Arduino Nano and utilises Manifold Absolute Pressure (MAP) and a knock sensor to determine the ignition timing on a Peugeot 205 Tu9 45Ch. It would appear that the ECU has been developed over a number of revisions and has been in operation for over a year.
I’ve made another video which talks through the way that the closed loop ignition control system works.
It may help to watch the video explaining the whole system first here: http://scottsnowden.co.uk/?p=337