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⌂ ∞ ▽ Elite on the BBC Micro and NES

Version analysis of MT29

This code appears in the following versions (click to see it in the source code):

Code variations between these versions are shown below.

       Name: MT29
       Type: Subroutine
   Category: Text
    Summary: Move to row 6, switch to white text, and switch to lower case when
             printing extended tokens
  Deep dive: Extended text tokens



 This routine sets the following:

   * YC = 6 (move to row 6)

 Then it calls WHITETEXT to switch to white text, before jumping to MT13 to
 switch to lower case when printing extended tokens.



.MT29

Code variation 1 of 2Related to Elite's use of the Tube

Tap on a block to expand it, and tap it again to revert.

Docked, Master
6502SP
 LDA #6                 \ Move the text cursor to row 6
 STA YC

 LDA #6                 \ Move the text cursor to row 6
 JSR DOYC

Code variation 2 of 2Related to the screen mode

This variation is blank in the Disc (docked) version.

Tap on a block to expand it, and tap it again to revert.

Master
6502SP
 LDA #CYAN              \ Set white text
 STA COL

 JSR WHITETEXT          \ Set white text

 JMP MT13               \ Jump to MT13 to set bit 7 of DTW6 and bit 5 of DTW1,
                        \ returning from the subroutine using a tail call