qa.hlp (Table of Contents; Topic list)
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Int 15H Function 84H
   Summary  Notes  Back
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  Description:  Read Joystick      [AT] [PS/2]
 
  Returns the joystick switch settings and potentiometer values.
 
  Input                                      Output
  ═══════════════════════════════            ══════════════════════════════
  AH=84H                                     If function successful
  DX=subfunction                             Carry flag=clear
     00H to read switch settings             and, if called with DX=00H
     01H to read resistive inputs            AL=switch settings (bits 4-7)
                                             or, if called with DX=01H
                                             AX=A(x) value
                                             BX=A( y) value
                                             CX=B(x) value
                                             DX=B( y) value
                                             If function unsuccessful
                                             Carry flag=set
                                    -♦-