This repository contains code intended for the ESP8266. One of its purposes is to demonstrate how SPIFFS might be used for containing an application's configuration data. And it is based on my ESP8266-config-data repository, but with many extensive improvements and modifications.
The other purpose of this repository is to provide a starting point for future projects that require the ability to obtain external configuration data.
I had continued some work using my ESP8266-config-data repository as a starting point. And my new design had the following requriements -
- Configuration data is kept in files and formatted as JSON.
- Automatically connect to a WiFi access point that -
- Would be configured in
/data/wificfg.dat. - Has multiple access point choices that would be provided in the configuration file.
- Would be configured in
- The potential need for some additional configuration files -
- Application Configuration : Application name, and a debug output mute flag.
- Remote Server Configuration : remote server addresses and port numbers to be selectable via a textual name or other identification.
- TBD
You will need the following -
- ESP8266 - I'm using a NodeMCU 1.0, and mine is a 12-E
- Arduino IDE - Installed and made ready for use with the ESP8266
- In addition to being able to compile code for the ESP8266 you will need an IDE plug-in for downloading the file(s) to the ESP8266 flash memory.
- The ArduinoJSON library is used in this application.
I dowloaded the most recent version of the plugin by going to https://github.com/esp8266/arduino-esp8266fs-plugin and clicking the "releases page" link in the README.
NOTE : I am running Windows 10. And this file, its instructions and any other information may or may not be influenced by that fact. Where possible I will note any windows specific items.
There are some discrepancies in the available on-line sources in regards to where to place the plug-in's jar file. In Windows I've found that the plugin will work as long as it's in one of two places. They are -
C:\Users\SOME_USER\Documents\Arduino- you might have to create atoolsfolder here, and then copy the contents of the plugin zip file into it.
OR
C:\Program Files (x86)\Arduino\tools- copy the contents of the plug-in zip file into this folder.
I've tested the plug-in separately in each of the locations and have had no issues.
The ArduinoJSON library should be installed via the library manager in the Arduino IDE. This application was built and tested with ArduinoJSON v5.11.0.
Start with an unmodified version of the code from this repository. Please use the following steps -
1) Run the Arduino IDE and go to the Tools menu and find Flash Size: and choose '4M (1M SPIFFS)'.
2) Open the ino file in the Arduino IDE and build & upload it to the ESP8266. Do not open the serial monitor.
3) Then go to the Tools menu and click on ESP8266 Sketch Data Upload.
Your SPIFFS along with the file it contains will be uploaded to the ESP8266. After that has completed open the serial monitor and reset the ESP8266.
You should see this in the serial monitor -
setup START
AppCfgData parsing JSON -
{"appname":"My Application","debugmute":false}
getAppName - My Application
getDebugMute - OFF
WifiCfgData parsing JSON -
{ "apoints":[
{"ssid":"your ssid-1 here","pass":"your wifi password-1 here"},
{"ssid":"your ssid-2 here","pass":"your wifi password-2 here"}
],"apcount":2}
getAPCount - 2
AP #0
getSSID - your ssid-1 here
getPASS - your wifi password-1 here
AP #1
getSSID - your ssid-2 here
getPASS - your wifi password-2 here
Attempting connection to -
ssid : your ssid-1 here
pass : your wifi password-1 here
connected? - no
Attempting connection to -
ssid : your ssid-2 here
pass : your wifi password-2 here
connected? - no
setupWiFi ERROR! - Could not connect to -
your ssid-1 here
your ssid-2 here
setup DONE - Could not connect to -
your ssid-1 here
your ssid-2 here
Since all attempts failed the on-board LED will flash with an interval of ERR_TOGGLE_INTERVAL (defined in ESP8266-config-data-V2.ino).
Let's edit the configuration data and change at least one of the SSID and password combinations to something usable.
1) Edit the wificfg.dat file, it's found in /data
2) The contents currently look like this -
{ "apoints":[
{"wifi-ssid":"your ssid-1 here","wifi-pass":"your wifi password-1 here"},
{"wifi-ssid":"your ssid-2 here","wifi-pass":"your wifi password-2 here"}
],"apcount":2}
3) If you're only going to have one access point in the configuration file, then it should look like this -
{ "apoints":[
{"wifi-ssid":"your ssid-1 here","wifi-pass":"your wifi password-1 here"}
],"apcount":1}
4) Save and close the file as _wificfg.dat (note the underscore at the beginning of the file name, since this file now contains sensitive information it will be ignored via .gitignore and cannot be committed)
5) Run the Arduino IDE and go to the Tools menu and find Flash Size: and choose '4M (1M SPIFFS)'.
6) Open the ino file in the Arduino IDE and edit line 29 to read as if(setupWiFi("/_wificfg.dat")), then build & upload it to the ESP8266. Do not open the serial monitor.
7) Then go to the Tools menu and click on ESP8266 Sketch Data Upload.
After the SPIFFS has uploaded you can open the serial monitor and reset the ESP8266. You should now see something like this -
setup START
AppCfgData parsing JSON -
{"appname":"My Application","debugmute":false}
getAppName - My Application
getDebugMute - OFF
WifiCfgData parsing JSON -
{ "apoints":[
{"wifi-ssid":"usable_SSID_1","wifi-pass":"wifipassw1"},
{"wifi-ssid":"usable_SSID_2","wifi-pass":"wifipassw2"}
],"apcount":2}
getAPCount - 2
AP #0
getSSID - usable_SSID_1
getPASS - wifipassw1
AP #1
getSSID - usable_SSID_2
getPASS - wifipassw2
Attempting connection to -
ssid : usable_SSID_2
pass : wifipassw2
connected? - yes
ip : 192.168.0.14
mac : 60:01:00:00:00:02
host: ESP_000002
Connection Attempt Stats :
attempts = 1
time = 3
rssi = -37 dBm
SrvCfgData parsing JSON -
{
"http":{"addr":"192.168.0.26","port":80},
"devapi":{"addr":"192.168.0.26","port":4843},
"websock":{"addr":"192.168.0.26","port":8080}
}
label = http
addr = 192.168.0.26
port = 80
label = devapi
addr = 192.168.0.26
port = 4843
label = websock
addr = 192.168.0.26
port = 8080
setup DONE - No Errors
Where usable_SSID_1, usable_SSID_2 and wifipassw1, wifipassw2 are the values you edited in the /data/_wificfg.dat file.
When the connection is successful the on-board LED will flash with an interval of TOGGLE_INTERVAL (defined in ESP8266-config-data-V2.ino). However if an error has occurred the LED will flash with an interval of ERR_TOGGLE_INTERVAL.
In appcfg.dat change debugmute to true and upload the sketch data. Reset and the majority of debug output will be muted.
To fully understand ArduinoJson and how to properly determine the appropriate size of the buffer needed for your JSON data I recommend that you read the following -
- ESP8266 SPIFFS - Flash File System documentation, read this first - http://esp8266.github.io/Arduino/versions/2.3.0/doc/filesystem.html
- ArduinoJson documentation, start here - https://bblanchon.github.io/ArduinoJson/
- ArduinoJson Avoiding Pitfalls, this provides a very good explanation of common pitfalls as related to the ArduinoJson memory model - https://bblanchon.github.io/ArduinoJson/doc/pitfalls/
- ArduinoJson Memory Model, this explains how the memory model is allocated and information regarding buffer sizes and methods of allocation - https://bblanchon.github.io/ArduinoJson/doc/memory/
- ArduinoJson Assistant is a tool to aid in determining the correct buffer size based on a sample of the JSON you are working with - https://bblanchon.github.io/ArduinoJson/assistant/