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Official Name: PullDownChk

BCALL Address: 45CD

Checks for and processes any keys relating to menus.


  • A = key press


  • Carry flag set if menu requires further keypresses.
  • Carry flag reset if a final keypress is returned in A (might be the same as the original keypress)

Registers Destroyed

  • unknown


Calling this immediately after GetKey will allow OS menus to appear during execution of your program. The output of this routine may be an unprocessed key or it may be the result of a menu action. For instance if a=kenter was sent to this routine while entry 2 is highlighted in the Draw menu, the output of this routine would be a=kLine.


 B_CALL GetKey
 B_CALL PullDownChk
 jr c,getmenukeyloop ;Loop if more keypresses are needed
 ;After the loop, A holds a keypress value
ld a,kDraw
B_CALL PullDownChk ;on LCD the draw menu should be visable
ld a,kDown
B_CALL PullDownChk ;cursor should move from entry 1 to entry 2
ld a,kEnter
B_CALL PullDownChk ;output of routine should be kLine