This option can be enabled to permit the user to specify a custom line of text that is displayed on the screen as the keyer starts up.
Firstly, to use this option your keyer implementation requires a display.
The option, OPTION_PERSONALIZED_STARTUP_SCREEN is in the file keyer_features_and_options.h and it can be enabled by uncommenting that line.
The custom text string is defined in keyer_settings.h in the line -
#define custom_startup_field "AB1XYZ Bob"
AB1XYZ Bob, is simply an example of a callsign and name to display. You can change the text enclosed in double quotations to anything you want. Take care to ensure that the length of that custom text string (excluding the double quotation characters) is not more than the number of columns on the display in use.
How the text is displayed will depend on the number of lines that the display has, and for a two line display the option #define OPTION_DO_NOT_SAY_HI also needs to be enabled so that the second line is available for the display of the custom text. With a four line display it not necessary to enable the option #define OPTION_DO_NOT_SAY_HI as the custom text will be displayed on the third line of the display.
The custom text string will be displayed, centre aligned, on the second or third line. The number of rows on the display is set with the parameter LCD_ROWS in the file keyer_settings.h
If the display is specified to have three or more rows then the custom line of text is displayed on the third line (and we can still say 'hi' on the second line) and if we have four or more lines then additionally, for information, the code version is displayed on the fourth line.
No checking of the length of the custom text string is performed. It is the responsibility of the end user to ensure that the custom text string length does not exceed the number of columns on the display.