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*                          KBDIN                                   *

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                  name kbdin
                  entry kbdin
                  ext charin

BIOS equ 5
CHECK equ 0Bh   ;BIOS function code for check-console-keyboard

;FUNCTION:checks the keyboard.If a key has been struck
;returns with ASCII in A,else A=0.

;CALLS:CHARIN

KBDIN:            push h
                  push d
                  push b
                  mvi c,CHECK
                  call BIOS   ;now if a key was
                              ;struck,A(0)=1
                  rrc         ;so rotate A(0) into
                              ;carry & check.
                  jrc yes 
                  xra a       ;if not,clear A
kbdex:            pop b       ;& depart.
                  pop d
                  pop h
                  ret  
yes:              call CHARIN ;ifso get ASCII
                  jmpr kbdex

                  end kbdin

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