|Syntax||screen = SCREEN_BASE(#channel)|
This function is handy for Minerva users, who have 2 screens to play with. The function returns the address of the start of the screen memory for the appropriate channel.
If the returned address is negative, consider it to be a QDOS error code. (-6 means channel not open & -15 means not a SCR_ or CON_ channel.)
SCREEN_BASE allows you to write programs that need not make guesses about the whereabouts of the screen memory, or assume that if VER$ gives a certain result, that a Minerva ROM is being used, this may not always be the case. Regardless of the ROM in use, this function will always return the screen address for the given channel.
PRINT HEX$(SCREEN_BASE(#0), 24)