SCREEN 7,8,9 "Illegal Function Call" Using Foreground COLOR 0 (22036)

SUMMARY

Executing the COLOR statement with a zero (0) as the foreground color gives "Illegal Function Call" on the EGA SCREEN modes 7, 8, and 9. For example:

   10 SCREEN 9
   20 COLOR 0,0   ' Gives "Illegal function call"
				

This is because zero (0) is not within the allowed range of attributes with the EGA. The range of attributes is 1 to 3 for an EGA with 64K, and 1 to 15 for an EGA with more than 64K of memory.

You can work around this behavior by using the PALETTE statement to reassign the color of zero to another attribute number. This can be accomplished by doing the following:

   DIM Pal%(16)
   SCREEN 7
   Pal%(0) = 15
   Pal%(15) = 0
   PALETTE USING Pal%(0)
   COLOR 15,1
   CLS
				

This information applies to QuickBasic versions 2.00, 2.01, 3.00, 4.00, 4.00b, and 4.50; to Microsoft Basic Compiler versions 6.00 and 6.00b for MS-DOS, and to Microsoft Basic Professional Development System (PDS) versions 7.00 and 7.10 for MS-DOS.