HP Vectra Technical Reference Manual page 452

Bit ATR Name Data Description
6:5
ATLSUBADD These bits specify what type of major and minor
addresses the driver requires.
ATR___NOADDR 00
The driver does not require any address.
ATLMAJOR 01 This driver requires that a major address be
specified and stored in the parent driver's
DH__MAJOR header record. The range of
possible major addresses is 0 through the
contents of this header's DH_MAJOR.
ATLMINOR
10
This driver requires that a minor address be
specified and stored in the parent driver's
DH_MINOR header record. The range of
possible MINOR addresses is 0 through the
contents of this header's DH_MINOR. A driver
cannot require a minor address unless it also
requires a major address.
ATR_MID
11
This driver requires a major address, a minor
address, and a mid address. The minor address
field is split into an upper and a lower nibble,
with
~he
upper nibble indicating the mid address
and the lower nibble indicating the minor
address. The range of addresses possible is
specified by the child physical driver.
4 ATLPSHARE
0
This driver cannot be shared between several
parent drivers.
3
ATL_CSHARE
0
This driver cannot be shared between several
child drivers.
2
ATLROM 1 This driver header is in ROM and cannot be
altered unless copied to RAM. 1 Reserved
1 ATR_YIELD Reserved.
0 Reserved
The DH_NAME_-'NDEX is used to derive the
localization string index of the driver. This is given
by
the function F_STLGET_STRING in the
V__SYSTEM driver. See Section 9 for additional
information.
The DH_V_DEFAULT field contains the driver's
default vector address.
Driver Writer's Guide 443