The ZES1 (I/O processor) subroutine - Elite on the BBC Micro and NES

       Name: ZES1                                                    [Show more]
       Type: Subroutine
   Category: Utility routines
    Summary: Zero-fill the page whose number is in X
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * clr_scrn calls ZES1


 Arguments:

   X                    The page we want to zero-fill


.ZES1

 LDY #0                 \ If we set Y = SC = 0 and fall through into ZES2
 STY SC                 \ below, then we will zero-fill 255 bytes starting from
                        \ SC - in other words, we will zero-fill the whole of
                        \ page X

Utility routines: ZES1

[Elite-A, I/O processor]