SMDI, Windows, and the ASR-X

NOTE: As of OS 2.67/3.04, this "trick" is not required. With these Operating Systems and later, SMDI works without any effort. However, the below is retained for completeness and informational purposes.

Ensoniq has implemented SMDI/SCSI communication with the ASR-X starting is revision 2.5. SMDI is a general protocol devised in 1991 to standardize SCSI communication between musical-related instruments.

However, due to differences in the way Windows and the ASR-X implement SCSI communication (see below), SMDI communication requires "tricking" Win95/98.

The ASR-X is identified as a DEV_TYPE_PROCESSOR. For some reason, Windows (actually, ASPI - Adaptec SCSI Protocol Interface - which is the miniport driver sparrow.mpd) doesn't recognize these types of SCSI devices upon bootup; or if it does, the SCSI bus is reset and the ASR-X is "forgotten". So when you use your SMDI enabled program (Sound Forge, others), the ASR-X can't be found.

However, ASPI can see the ASR-X through this "trick". An ASR-X mailing list subscriber ("Funkey") came up with this.

We have tested this with a couple Adaptec cards (1542, 1505), using the latest ASPI layer. It probably works with most SCSI setups. If your SCSI card has a hardware BIOS that is uses upon computer startup, you probably will have to bypass that - check your card documentation.

More on SCSI-ASR-X Issues
SMDI is implemented in the ASR-X correctly. The problem is not SMDI itself - it's the computers (mainly PC/Windows host adapters) ability to see the ASR-X in the first place. Whether that's the ASR-X's fault or the computers fault - that's for the courts to decide. =)

Ensoniq designed SMDI apparently with Mac's in mind, so since the Mac SCSI didn't have a problem seeing the ASR-X (SCSI DEV_PROCESSOR device type) continuously, there's "no problem". Unfortunately, the PC has a problem seeing the ASR-X, thus a trick is needed to "link up" to the PC.

Ensoniq apparently has addressed the issue in a beta-ASR-X Pro OS - so it perhaps is a matter of waiting an indefinite period for the next OS for PC users for hassle-free (or even possible, in some cases) operation.

Perhaps the SMDI compatibility announcement (since 2.5, BTW) should have had an asterisk (*) on it concerning PC/Windows host adapters, but I guess Ensoniq didn't because of marketing reasons or they were oblivious to the problem, or some other reason.

Contributors: "fUNkeY" and Garth Hjelte

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