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ADB(4)                       Device Drivers Manual                      ADB(4)

NAME
     adb - Apple Desktop Bus driver

SYNOPSIS
     adb* at obio?

     options MRG_ADB

     #include <machine/adbsys.h>

DESCRIPTION
     The Apple Desktop Bus (ADB) is the single-master, multiple-slave, low-
     speed serial bus interface used by Macintosh computers to connect input
     devices such as keyboards, mice, trackpads, trackballs, and graphics
     tablets to the machine.  NetBSD provides support for the Apple Desktop
     Bus as found on all supported mac68k models, as well as macppc models
     with on-board ADB (PowerBooks and "Old World" models).

     The adb driver accesses the ADB controller using the so-called "HWDIRECT"
     method.  This method of access bypasses the Macintosh ROM and uses only
     NetBSD routines for ADB access.  This is the only method supported on
     macppc and is the default for mac68k systems.

     On mac68k systems there is an alternate method of accessing the ADB
     controller.  With the Macintosh ROM Glue (MRG) method, the routines
     written for MacOS are used.  To enable this method of ADB access,
     uncomment the line:

     options MRG_ADB

     in your kernel configuration file.

     The ioctl(2) call is used to control the ADB event device.  The following
     is a list of available ioctl(2) commands:

     ADBIOC_DEVSINFO   Get ADB Device Info

                       The adb event device will return an array of
                       information containing an entry for each device
                       connected to the bus.  Each entry contains the current
                       address, default address, and handler ID for the
                       corresponding ADB device.

     ADBIOC_GETREPEAT  Get Keyboard Repeat Info

                       Returns a structure containing the current keyboard
                       repeat delay and keyboard repeat interval.

     ADBIOC_SETREPEAT  Set Keyboard Repeat Rate

                       Sets the keyboard repeat delay and interval to the
                       values specified by argp.

     ADBIOC_RESET      ADB Reset

                       Perform a reset of the ADB which will reinitialize all
                       of the devices attached to the bus.

     ADBIOC_LISTENCMD  ADB Listen Command

                       Send data to the register of the ADB device specified
                       by argp.  This command is not fully implemented at this
                       time.

SUPPORTED DEVICES
     NetBSD includes support for the following ADB devices, sorted by driver
     name:

           abtn  ADB mouse button?

           aed   ADB event device

           akbd  ADB keyboard

           ams   ADB mouse

           apm   APM emulation

FILES
     /dev/adb  The ADB event device.

DIAGNOSTICS
     aed0 at adb0 addr 0: ADB Event device  This is a normal autoconfiguration
     message noting the presence of the adb event device.

     adb0 at obio0 offset 0x16000 irq 18: 2 targets  A standard
     autoconfiguration message indicating the initialization of the ADB
     subsystem.

     adb: no devices found.  No ADB devices were found to be connected to the
     bus during autoconfiguration.

     adb: using %s series hardware support.  Indicates the class of ADB
     hardware support the machine uses.

     adb: hardware type unknown for this machine.  The ADB hardware in this
     machine is currently unsupported.

     adb: no ROM ADB driver in this kernel for this machine.  The kernel lacks
     the necessary Macintosh ROM Glue (MRG) support for accessing the ADB
     hardware on this machine.

     adb: using serial console.  A serial console will be used for user input
     rather than the ADB event device.

     adb: %s at %d.  An ADB device of the type specified by %s has been found
     at location %d.

SEE ALSO
     aed(4), akbd(4), ams(4), apm(4)

HISTORY
     The adb interface first appeared in NetBSD 0.9.  It has been under
     development ever since.

AUTHORS
     Bradley A. Grantham wrote the original adb driver, including the MRG
     support.  The hardware direct interface was written by John P.
     Wittkowski.  The PowerManager interface was written by Takashi Hamada.

BUGS
     ⊕   Not every class of ADB hardware is supported yet.

     ⊕   The talk command is currently unimplemented.

     ⊕   The listen command is not implemented yet.

     ⊕   Not all multi-button mice are currently supported.

     ⊕   Only mapped and relative-position ADB devices (i.e. keyboards and
         mice) are supported.  Thus absolute-position and other exotic devices
         will not work.

     ⊕   Some of the diagnostic messages in this man page need to be updated.

     Some mac68k machines contain so-called dirty ROM.  These machines are
     the: Mac SE/30, Mac II, Mac IIx, and Mac IIcx.  Machines with dirty ROM
     may experience trouble booting if the MRG code is used, especially under
     the following conditions:
           ⊕   Both a keyboard and a mouse are not attached to the computer.
           ⊕   An extended keyboard is attached to the computer.

     On (some) machines with dirty ROM, the ROM indicates the presence of a
     "ghost" keyboard or mouse.  When this nonexistent device is probed for,
     the result is an infinite loop.  This is believed to be triggered by the
     adb driver probing for extended mice, and non-EMP Logitech mice.

NetBSD 10.99                    August 31, 2018                   NetBSD 10.99