Technical data

Option ROM, Continued

Name Description

Option revision This number controls changes

in both the option hardware and

ﬁrmware.

Option index value An index value of the last DCT entry.

A zero in this ﬁeld indicates a single

DCB for the device, a one indicates

two device control blocks for this

device. An option that occupies the

storage option slot can have the

values of zero or one. An option that

occupies the video option slot can

have the values of zero, one, or two.

Reserved for expansion These 32 bytes are reserved.

Device conﬁguration table

template

The device implemented by the

option must have an associated

device conﬁguration table template.

The DCT contains static and

dynamic data and pointers to code

required for the device.

2–19