This is where I collect my thoughts on everything technology. Below you'll find a collection of my most recent blog posts. For a full list of blog posts, visit the blog section of my site. For information on a number of my technical projects visit my projects section. And for more information about me, check out my about section.
Enjoy!
-- Patrick Blesi
I recently created a number of wifi touch lights to help my family keep in “touch” with each other. It was a fun project, but there was a bit of a challenge getting everyone’s light set up. I was giving the lights as gifts, and I did not want my family members (some of them not as tech savvy) to have to go through the Photon wifi setup using a web application or mobile app.
Luckily, Particle’s API provides a way to set wifi credentials for your Photon from within the source code of the flashed program. They provide great documentation describing this API, however they don’t provide any tutorials for the steps necessary to set wifi credentials from within your code. Below I describe how to set up wifi credentials manually for your Particle Photon.
The first step is to place your photon in SEMI_AUTOMATIC mode. This must be done outside of the setup and loop functions.
SYSTEM_MODE(SEMI_AUTOMATIC);
setup() {
// Setup code goes here
}
void loop() {
// Do more stuff here
}
SEMI_AUTOMATIC mode does not immediately connect to the particle cloud, but waits until you manually call Particle.connect() to connect to the cloud. Once connected to the cloud, your particle automatically manages the connection.
Once your Photon is put into SEMI_AUTOMATIC mode, you can manually set up your wifi connection at the beginning of your setup function. You can specify up to five sets of credentials for Photons and seven sets of credentials for Cores. If more credentials are specified, the oldest credentials will be overwritten.
SYSTEM_MODE(SEMI_AUTOMATIC);
void setup() {
WiFi.on();
WiFi.disconnect();
WiFi.clearCredentials();
WiFi.setCredentials("SSID", "password", WPA2, WLAN_CIPHER_AES);
WiFi.setCredentials("ALTERNATE_SSID", "other_password", WPA2, WLAN_CIPHER_AES);
WiFi.connect();
waitUntil(WiFi.ready);
Particle.connect();
// Rest of setup code goes here
}
void loop() {
// Do more stuff here
}
You can find more details on setCredentials in the Particle Reference Docs. The first argument is the name of the wifi access point/router. The second argument is the password to connect to the wifi access point. Both the third and fourth arguments are required if the access point is not accessible when the credentials are set.
The third argument specifies the authentication procedure. It must be one of WPA2, WPA, or WEP. WPA2 is the most modern and secure authentication procedure, and WEP is the oldest. The fourth argument specifies the security cipher. Possible security cipher options are WLAN_CIPHER_AES, WLAN_CIPHER_TKIP, and WLAN_CIPHER_AES_TKIP. Of these WLAN_CIPHER_AES is the most modern and secure, and WLAN_CIPHER_TKIP is the oldest. WLAN_CIPHER_AES_TKIP is a mixed mode cipher configuration.
This gives you a working solution, but you can clean this code up a bit by placing the wifi setup code in its own function:
SYSTEM_MODE(SEMI_AUTOMATIC);
setup() {
setupWifi();
// Rest of setup code goes here
}
void loop() {
// Do more stuff here
}
void setupWifi() {
WiFi.on();
WiFi.disconnect();
WiFi.clearCredentials();
WiFi.setCredentials("SSID", "password", WPA2, WLAN_CIPHER_AES);
WiFi.setCredentials("ALTERNATE_SSID", "other_password", WPA2, WLAN_CIPHER_AES);
WiFi.connect();
waitUntil(WiFi.ready);
Particle.connect();
}
This is a pretty good solution, but if you commit your code to a source code management system like Git (which you should), then this makes it hard to commit your code without commiting your wifi credentials. This can be remedied by placing our credentials in a separate file:
/*
* src/wifi_creds.h
*/
// See https://docs.particle.io/reference/firmware/photon/#setcredentials- for details
struct credentials { char *ssid; char *password; int authType; int cipher; };
const credentials wifiCreds[] = {
// Set wifi creds here (last entry will be tried first when connecting)
// {.ssid="SSID", .password="password", .authType=WPA2, .cipher=WLAN_CIPHER_AES}
};
/*
* src/main.ino
*/
#include "wifi_creds.h"
SYSTEM_MODE(SEMI_AUTOMATIC);
setup() {
setupWifi();
// Rest of setup code goes here
}
void loop() {
// Do more stuff here
}
void setupWifi() {
WiFi.on();
WiFi.disconnect();
WiFi.clearCredentials();
int numWifiCreds = sizeof(wifiCreds) / sizeof(*wifiCreds);
for (int i = 0; i < numWifiCreds; i++) {
credentials creds = wifiCreds[i];
WiFi.setCredentials(creds.ssid, creds.password, creds.authType, creds.cipher);
}
WiFi.connect();
waitUntil(WiFi.ready);
Particle.connect();
}
You can commit src/wifi_creds.h to be used as a template, and then not commit this file when you have added credentials to the wifiCreds array.
What if you want to flash firmware onto your Photon, but don’t want to overwrite the wifi credentials currently on your Photon? You can make one more tweak to your code to allow for updating the Photon’s firmware without manually specifying wifi credentials:
/*
* src/wifi_creds.h
*/
// Uncomment the line below if specifying credentials in this file
// #define WIFI_CREDENTIALS_SPECIFIED
// See https://docs.particle.io/reference/firmware/photon/#setcredentials- for details
struct credentials { char *ssid; char *password; int authType; int cipher; };
const credentials wifiCreds[] = {
// Set wifi creds here (last entry will be tried first when connecting)
// {.ssid="SSID", .password="password", .authType=WPA2, .cipher=WLAN_CIPHER_AES}
};
/*
* src/main.ino
*/
#include "wifi_creds.h"
#ifdef WIFI_CREDENTIALS_SPECIFIED
SYSTEM_MODE(SEMI_AUTOMATIC);
#endif
setup() {
#ifdef WIFI_CREDENTIALS_SPECIFIED
setupWifi();
#endif
// Rest of setup code goes here
}
void loop() {
// Do more stuff here
}
void setupWifi() {
WiFi.on();
WiFi.disconnect();
WiFi.clearCredentials();
int numWifiCreds = sizeof(wifiCreds) / sizeof(*wifiCreds);
for (int i = 0; i < numWifiCreds; i++) {
credentials creds = wifiCreds[i];
WiFi.setCredentials(creds.ssid, creds.password, creds.authType, creds.cipher);
}
WiFi.connect();
waitUntil(WiFi.ready);
Particle.connect();
}
By commenting or uncommenting #define WIFI_CREDENTIALS_SPECIFIED you can control if code-specified credentials are placed on the Photon.
Setting up particle projects in this way will give you the flexibility to set your Photon’s wifi credentials manually, without having to use additional tools such as Particle’s mobile or web applications.
Cheers!