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Elite on the BBC Micro and NES

Keyboard: TT214, Removed

[Elite-A, Docked]

Name: TT214, Removed [Show more] Type: Subroutine Category: Keyboard Summary: Ask a question with a "Y/N?" prompt and return the response
Context: See this subroutine in context in the source code References: No direct references to this subroutine in this source file

Arguments: A The text token to print before the "Y/N?" prompt
Returns: C flag Set if the response was "yes", clear otherwise
\ --- Mod: Code removed for Elite-A: ------------------> \.TT214 \ \.TT221 \ \ JSR TT27 \ Print the text token in A \ \ LDA #206 \ Print extended token 206 ("{all caps}(Y/N)?") \ JSR DETOK \ \ JSR TT217 \ Scan the keyboard until a key is pressed, and return \ \ the key's ASCII code in A and X \ \ ORA #%00100000 \ Set bit 5 in the value of the key pressed, which \ \ converts it to lower case \ \ CMP #'y' \ If "y" was pressed, jump to TT218 \ BEQ TT218 \ \ LDA #'n' \ Otherwise jump to TT26 to print "n" and return from \ JMP TT26 \ the subroutine using a tail call (so all other \ \ responses apart from "y" indicate a no) \ \.TT218 \ \ JSR TT26 \ Print the character in A, i.e. print "y" \ \ SEC \ Set the C flag to indicate a "yes" response \ \ RTS \ Return from the subroutine \ --- End of removed code ----------------------------->