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⌂ ∞ Elite on the BBC Micro and NES

Drawing lines: NLIN4

[NES version, Bank 7]

       Name: NLIN4                                                   [Show more]
       Type: Subroutine
   Category: Drawing lines
    Summary: Draw a horizontal line on tile row 2 to box in a title

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * JMTB calls NLIN4
             * SVE calls NLIN4
             * TT213 calls NLIN4




.NLIN4

 LDA #4                 ; Set A = 4, though this has no effect other than making
                        ; the BNE work, as NLIN2 overwrites this value

 BNE NLIN2              ; Jump to NLIN2 to draw the line, (this BNE is
                        ; effectively a JMP as A is never zero)

 LDA #1                 ; These instructions appear to be unused
 STA YC
 LDA #4