Utility routines: ZESNEW

       Name: ZESNEW                                                  [Show more]
       Type: Subroutine
   Category: Utility routines
    Summary: Zero-fill memory from SC(1 0) to the end of the page
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * CHPR calls ZESNEW


 Zero-fill from address SC(1 0) + Y to SC(1 0) + $FF.


 Arguments:

   Y                    The offset from SC(1 0) where we start zeroing, counting
                        up to $FF

   SC(1 0)              The starting address of the zero-fill


 Returns:

   Z flag               Z flag is set


.ZESNEW

 LDA #0                 ; Load A with the byte we want to fill the memory block
                        ; with - i.e. zero

.ZESNEWL

 STA (SC),Y             ; Zero the Y-th byte of the block pointed to by SC

 INY                    ; Increment the loop counter

 BNE ZESNEWL            ; Loop back to zero the next byte

 RTS                    ; Return from the subroutine