Class used for the creation and storage of a pairing QR Code (just the text, not the actual graphic) from a HAP Setup Code, HAP Category, and HAP Setup ID. The resulting QR Code text is output to Serial Monitor whenever the SetUp Code is generated or changed. The user can type this text into any QR Generator to create a QR Code graphic for pairing the device to HomeKit (in lieu of creating a printed tag of the Setup Code formatted using the Scancardium font).
Though not needed for HomeSpan, this class implements all the settings and parameters (such as Version and Reserved) used to generate any Apple HomeKit QR Code.
This class is used internally by HomeSpan and is not intended for the end-user.
HomeSpan now broadcasts a Hashed Setup ID as MDNS "sh", which is used when pairing with a QR Code instead of a Setup Code. A text version of the resulting QR code is output to the Serial Monitor whenever the 9-digit Setup Code is generated or changed. The text version of the QR code can then be input into any QR Code Generator to create a pairable QR Code.
The default Setup ID used to create the Hashed Setup ID is "HSPN". This can be changed with homeSpan.setQRCode(const char *id), where id is exactly 4 alphanumeric characters. If not, the request to change the Setup ID is silently ignored and remains "HSPN."
This allows the Serial Monitor to send NL or CR/NL at end of each line. A newline ('\n') must be at the end to terminate reading from the Serial Monitor, but any preceeding carriage returns are stripped out.
HomeSpan defaults to running the HAP Server on port 80 (the standard HTTP port). This method allows the user to over-ride the default and have HomeSpan run the HAP Server on any other port.
ALSO: In updating this portion of the code, identified an additional parameter to the ESP32 version of WiFiServer that allows one to specify the number of simultaneous Server connections. The ESP32 default is 4, which suggests that the ESP32 was internally juggling connections that HomeSpan was keeping open (since the HomeSpan default is 8 connections).
This WiFiServer call has been updated to now specify both the port number AND the number of maximum simultaneous connections (to match whatever has been set by HomeSpan). This may or may not result in improving performance when more than 4 clients are connected.
HomeSpan