If you ever looked into the directory of your reference disk you will have noticed a lot files with the ending .ADF
Some of them have the funny "@"-character as first letter, some have not.
But which one is needed for a particular card ?
At that point we need to run through a little excurs about the Adaptercard ID.
This card-ID is a 4-character hexadecimal string, which can be read by the MCA-bus from the card. This string has the numbers 0 - 9 and the letters A - F inside, the hexadecimal ranging goes from 0000 to FFFF - which is 65.536 for us decimal humans.
The card-ID string was given from IBM to the cards' manufacturer and it has to be present at the card to be read out with a small program. The original idea was, that the card-ID is unique for any particular card series (not for any single card at all - that would not work with only 4 bytes). From the principle this concept is still applicable and you could identify most of the MCA-cards by reading its card-ID. However: there were some manufacturers that gave the same card-ID to a whole family of cards, which might cause some confusion and there were older cards replaced by totally different cards which accidently have the same ID, which is also a bit misleading.
Some years ago I wrote a software called QBMCA, which does the identification of MCA cards. It can be downloaded from the QBMCA-page.
It is free - the method to extract and use it is described on the page as well.
The basic file-format for the usual ADF is always
Assumed you have found out the ID of a particular card (either with QBMCA or another tool) and it is -for example- 0F1F, then you will have to look for files that have the sequence 0F1F and the ending .ADF in the file-name.
If you used my QBMCA you will already know that this card-ID belongs to the "Adaptec AHA-1640 SCSI Host-Adapter"
The AHA-1640 uses only a single base-ADF, which has the name @0F1F.ADF.
All base-ADFs are editable ASCII-textfiles.
Assumed the card-ID is FDDF and it is an "IBM Enhanced 80386 Memory Expansion Adapter" you will find some more files with the combination FDDF inside:
* non-editable Assembler file
And you will need at least the 3 ADFs for proper operation.
- @FDDF.ADF - the base-ADF (ASCII)
- CFDDF.ADF - a so-called Adapter Description Program (ADP) *
- IFDDF.ADF - the adapters' initialization file *
- @FDDF.DGS - which is a Diagnostic-file for the adapter *
What are the other files for ? These ones beginning with D, P, S, E and J ?
These files are used for systemboards (planars) and their setup.
As well as any adaptercard has a unique ID - so have the systemboards. The Mod. 55 planar for example has the Planar-ID FBFF and any file with D, P and S + FBFF.ADF referres to the Mod. 55 systemboard.
* non-editable Assembler file
- DFBFF.ADF - the Planar Description File (ASCII),
which defines the slots and the memory subsystem
- PFBFF.ADF - the Planar Programable Options File (ASCII),
which defines the various options on the planar
- SFBFF.ADF - the Planar Description Program *,
which automatically sets various options at power-on
- JFBFF.ADF - the Planar Init File *,
which is optional for some few machines
That leaves the E-.ADF, which is also a Planar Description File, but for the MCA Expansion units used with the mobile PCs. The 3550 Expansion unit has the planar-ID E9FF and you may find this:
- EE9FF.ADF - the Expansion Unit Description File (ASCII),
which describes the slots and NVRAM -if any-
So, now you know what the names come from - read on at the next chapter !