HIL(4)

NAME
hil - Human Interface Link device driver

DESCRIPTION
The Human Interface Link (HIL) is the interface used by the Series 300 computers to connect devices such as keyboards, mice, control knobs, and ID modules to the machine.

Special files /dev/hil[1-7] refer to physical HIL devices 1 through 7. /dev/hil0 is an artifact of a never-completed interface and is not currently useful for anything. In the current implementation, only one keyboard can be used for text-mode interaction via the ite(4) interface; other keyboards, if any, are accessible only via their /dev/hilN interfaces, as described here.

The device file that corresponds to a particular HIL device is determined by the order of the devices on the loop. For instance, if an ID module is the second physical device on the loop, then /dev/hil2 is the special file that should be used for communication with that module.

Communication with an HIL device is begun with an open system call. A process may open a device already opened by another process unless the existing process is operating in HP-UX compatibility mode, in which case it requires exclusive use of the device, or another process has the device open and is using HP-UX style device access (see HILIOCHPUX below).

In the current implementation, HP-UX style access is the only supported access method. This interface uses read(2) calls to receive packets of data representing events. (An interface using a memory area shared between the kernel and the user process was partially implemented, and remnants of it can be found in the include files and the driver, but it does not work and probably will be completely dropped in favor of a console interface providing better cross-port consistency.)

To receive events from a device, a user process uses open(2) to open the device, then uses the HILIOCHPUX ioctl (see below) to request HP-UX style access. Then data obtained with read(2) consists of a stream of packets, each of which has a five-byte header consisting of a one-byte length (including the header) and a four-byte timestamp, which is measured in hundredths of a second since some fixed reference point. The timestamp is stored in host-native byte order; copying it into a ‘long int’ variable with memcpy(3) or equivalent will give a useful result. Following this header is zero or more bytes, as received from the device. This manual page documents this data only minimally; see PACKET FORMAT below.

select(2) may be used in the usual way to detect input data.

ioctl(2) is used to control the HIL device. The ioctl commands (which unfortunately are defined in an include file, /usr/src/sys/arch/hp300/dev/hilioctl.h, not normally installed under /usr/include), are as follows. Many of these are functionally identical to ioctls HP-UX provides.

HILIOCID
    Identify and Describe

    The device will return up to 11 bytes of information describing the type and characteristics of the device. At the very least, 2 bytes of information, the device ID, and the Describe Record Header will be returned. Identical to the HP-UX HILID ioctl.

HILIOCSC
    Report Security Code

    Request the security code record from a device. The security code can vary from 1 byte to 15, and is only supported by some HIL devices. Identical to the HP-UX HILSC ioctl.

HILIOCRN
    Report Name

    An ascii string of up to 15 bytes in length that describes the device is returned. Identical to the HP-UX HILRN ioctl.

HILIOCRS
    Report Status

    An ascii string of up to 15 bytes in length that describes the current status of the device is returned. Identical to the HP-UX HILRS ioctl.

HILIOCED
    Extended Describe

    Additional information of up to 15 bytes is returned describing the device. This ioctl is similar to HILIOCID, which must be used first to determine if the device supports extended describe. Identical to the HP-UX HILED ioctl.

HILIOCAROFF
    Disable Auto Repeat

    Turn off auto repeat on the keyboard while it is in cooked mode. Identical to the HP-UX HILDKR ioctl.

HILIOCAR1
    Enable Auto Repeat

    Turn on auto repeat on the keyboard while it is in raw mode. The repeat rate is set to 1/30th of a second. Identical to the HP-UX HILER1 ioctl.

HILIOCAR2
    Enable Auto Repeat

    Turn on auto repeat on the keyboard while it is in raw mode. The repeat rate is set to 1/60th of a second. Identical to the HP-UX HILER2 ioctl.

    The following ioctls are specific to this implementation:

HILIOCBEEP
    Beep

    Generate a keyboard beep as defined by arg. arg is a pointer to two bytes of information; the first is the duration of the beep (microseconds), the second is the frequency of the beep (Hertz).

HILIOCHPUX
    Use HP-UX Read Interface

    Use HP-UX semantics for gathering data from this device. This call must be used before anything can be read from the descriptor.

PACKET FORMAT
When reading data from a device, events are received as data packets, with a header as described above. Here we provide (very rudimentary) documentation for the format of the device-dependent data, for at least one type of mouse and keyboard (specifically, the 46060A two-button mechanical mouse and 46021A keyboard); other mice and keyboards may or may not be similar.

The first byte of data is a bitmask. Only two bits have known meaning:

0x02
    The data portion contains mouse motion deltas, two signed 8-bit quantities, X delta first.

0x40
    The data portion contains a key or mouse button up/down event, one byte. The low bit is 0 if the event is a ‘down’ event, 1 if an ‘up’ event. The other seven bits identify the key or button, according to the table below.

If both bits are set, the mouse deltas appear before the button byte.

The known identifying values for key/button events are (only the 0xfe bits are listed):

0x04
    ‘Extend char’ (right-hand).
0x06
    ‘Extend char’ (left-hand).
0x08
    ‘Shift’ (right-hand).
0x0a
    ‘Shift’ (left-hand).
0x0c
    ‘CTRL’
0x0e
    ‘Break’ / ‘Reset’
0x10
    4, on the numeric keypad.
0x12
    8, on the numeric keypad.
0x14
    5, on the numeric keypad.
0x16
    9, on the numeric keypad.
0x18
    6, on the numeric keypad.
0x1a
    7, on the numeric keypad.
0x1c
    The comma key on the numeric keypad.
0x1e
    ‘Enter’, on the numeric keypad.
0x20
    1, on the numeric keypad
0x22
    The slash key on the numeric keypad.
0x24
    2, on the numeric keypad.
0x26
    The plus key on the numeric keypad.
0x28
    3, on the numeric keypad.
0x2a
    The asterisk key on the numeric keypad.
0x2c
    0, on the numeric keypad.
0x2e
    The minus key on the numeric keypad.
0x30
    B
0x32
    V
0x34
    C
0x36
    X
0x38
    Z
0x3e
    ‘ESC’ / ‘DEL’
0x42
    The second (counting from the left) of the four unmarked keys at the top right.
0x46
    The third (counting from the left) of the four unmarked keys at the top right.
0x48
    The period key on the numeric keypad.
0x4a
    The leftmost of the four unmarked keys at the top right.
0x4c
    The ‘Tab’ key on the numeric keypad.
0x4e
    The rightmost of the four unmarked keys at the top right.
0x50
    H
0x52
    G
0x54
    F
0x56
    D
0x58
    S
0x5a
    A
0x5e
    ‘Caps’
0x60
    U
0x62
    Y
0x64
    T
0x66
    R
0x68
    E
0x6a
    W
0x6c
    Q
0x6e
    ‘Tab’
0x70
    The digit-7 / ampersand key.
0x72
    The digit-6 / circumflex key.
0x74
    The digit-5 / percent-sign key.
0x76
    The digit-4 / dollar-sign key.
0x78
    The digit-3 / hash-mark key.
0x7a
    The digit-2 / at-sign key.
0x7c
    The digit-1 / exclamation-point key.
0x7e
    The backquote / tilde key.
0x80
    Left mouse button.
0x82
    Right mouse button.
0x90
    ‘Menu’
0x92
    ‘F4’
0x94
    ‘F3’
0x96
    ‘F2’
0x98
    ‘F1’
0x9c
    ‘Stop’
0x9e
    ‘Enter’ / ‘Print’
0xa0
    ‘System’ / ‘User’
0xa2
    ‘F5’
0xa4
    ‘F6’
0xa6
    ‘F7’
0xa8
    ‘F8’
0xac
    ‘Clear line’
0xae
    ‘Clear display’
0xb0
    The digit-8 / asterisk key.
0xb2
    The digit-9 / left-parenthesis key.
0xb4
    The digit-0 / right-parenthesis key.
0xb6
    The minus-sign / underscore key.
0xb8
    The equal-sign / plus-sign key.
0xba
    ‘Back space’
0xbc
    ‘Insert line’
0xbe
    ‘Delete line’
0xc0
    I
0xc2
    O
0xc4
    P
0xc6
    The left-bracket / left-brace key.
0xc8
    The right-bracket / right-brace key.
0xca
    The backslash / vertical-bar key.
0xcc
    ‘Insert char’
0xce
    ‘Delete char’
0xd0
    J
0xd2
    K
0xd4
    L
0xd6
    The semicolon / colon key.
0xd8
    The single-quote / double-quote key.
0xda
    ‘Return’
0xdc
    The arrow key pointing up and left.
0xde
    ‘Prev’
0xe0
    M
0xe2
    The period / less-than key.
0xe4
    The comma / greater-than key.
0xe6
    The slash / question-mark key.
0xea
    ‘Select’
0xee
    ‘Next’
0xf0
    N
0xf2
    The spacebar.
0xf8
    The left-pointing arrow key.
0xfa
    The down-pointing arrow key.
0xfc
    The up-pointing arrow key.
0xfe
    The right-pointing arrow key.

FILES
/dev/hil[1-7]
    Individual HIL loop devices.

ERRORS

[ENODEV]
    No such HIL loop device.

[ENXIO]
    HIL loop is inoperative.

[EBUSY]
    Another HP-UX process has the device open, or another BSD process has the device open, and is using it in HP-UX mode.

[EINVAL]
    Invalid ioctl specification.

BUGS
Requiring HILIOCHPUX to be able to read anything is gross. It is probably not worth fixing, though, because the whole hil/ite mechanism will probably be replaced with a more-or-less port-independent scheme in the foreseeable future.

HISTORY
The hil interface is