The following table shows the recommended ID values for vendors.
(Source: HITR - Micro Channel Adapter Design, phys. page 30)

ID (hex)	Definition
0000	Device Not Ready
0001 – 0FFF	Bus Master Devices
1000 – 4FFF	Not Specified
5000 – 5FFF	Direct Memory Access (DMA) Devices
6000 – 6FFF	Direct Program Control (including Memory Mapped I/O)
7000 – 7FFF	Storage *
7DB8 – 7DBF	Prototypes **
8000 – 81FF	Video
8200 – FFFE	IBM Products
FFFF	Device Not Attached

* Multiple-function adapters containing storage typically respond as storage.

** The adapter IDs hex 7DB8 through 7DBF are reserved for the prototyping, developing, and testing of adapters and adapter designs and for adapters used in the testing of system designs.
Note: Do not use these IDs for purposes other than the local development of your adapters or systems.

Warning: Not all manufacturers and products adhered to these guidelines! Many exceptions exist and unfortunately even some adapter IDs are shared by two or more unique boards...

More information about ADF files can be found HERE.