CodeView (cv.hlp) (Table of Contents; Topic list)
CodeView Error
     Flip/Swap option off - application output lost (CV1043)
 
     The program being debugged wrote to the display when Flip/Swap was
     off. The program output was lost.
 
     When flipping is on, video page 1 is normally reserved for
     CodeView, while programs by default write to video page 0.
     Programs that write to video page 1 must be debugged with swapping
     on.
 
     Turn Flip/Swap on to be able to view program output.
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