Topic       : TOS - The Operating System
Author      : 
Version     : tos.hyp (December 19, 2008)
Subject     : Programmieren/Atari
Nodes       : 3010
Index Size  : 93790
HCP-Version : 5
Compiled on : Atari
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View Ref-File4.17.5  gpio                                                       TOS

 Name:         »gpio« - Communication via the external DSP port

 Opcode:       138

 Syntax:       int32_t gpio( int16_t mode, int16_t data );

 Description:  The XBIOS routine gpio serves for communication via the 
               general purpose pins of the external DSP connector.

                mode  Meaning

                0     Setting the input/output direction. The lower 
                      three bits of data represent the general purpose 
                      pins. A set bit represents an output pin and a 
                      cleared bit an input pin.

                1     Read the three general purpose pins. Their state 
                      will be returned in the lower three bits of the 
                      returned value. data is ignored.

                2     Write the lower three bits of data to the 
                      corresponding general purpose pins. Afterwards 
                      the parameter data holds the new state of the 
                      general purpose pins.

 Return value: If successful, the function returns the value 0. If the 
               parameter data had the value 1, one obtains the state 
               of the general purpose pins.

 Availability: The function is only available on computers of the 
               Falcon series, or with extended XBIOS routines (_SND).

 Group:        Sound routines

 See also:     Binding   buffoper   buffptr   devconnect   dsptristate 
                 locksnd   setbuffer   setinterrupt   setmontracks 
               setmode   settracks   sndstatus   soundcmd   unlocksnd