IBM SCSI Microcode Versions

SCSILEVL Utility
8032-based SCSI Controllers
80188-based SCSI Controllers
80186-based SCSI Controllers

Content by David L. Beem (original HERE). Edited by Tomáš Slavotínek.
Last update: 14 Sep 2022 (synced with David's version dated 19 Jan 2021).


SCSILEVL Utility

Hidden away on one of the support diskettes, IBM has a small program named SCSILEVL.COM. It reports the microcode firmware version on most of the different IBM SCSI controllers used on Micro Channel (MCA) PS/2s (This page does not cover the SCSI RAID controllers that IBM had on its server models nor the rebranded Future Domain controller IBM called the Patriot). Besides being a little too simplistic for my tastes, the program doesn't work on a few IBM models (Industrial Gearbox 800, 8556/8557, and 9556/9557 PS/2s) that have SCSI implemented on the system planar.

I intend to expand the program somewhat, as well as document how it works. Most of the code is fairly easy to understand for those fluent in Assembler. For some sections, you may have to see a debugging program (like Microsoft's CodeView for DOS) single-step through the code on a system with IBM SCSI. I recommend running the programs only in a pure DOS environment!

The original SCSILEVL.COM program doesn't even check if it is running on an MCA system (the things IBM takes for granted)! I just find some areas worth improving, mainly to make it check all the IBM SCSI microcode versions. The interface can also be changed to be more grammatically correct (i.e. not identifying a planar SCSI controller as being on a "slot").

SCSILEVL.COM - IBM's original version (ZIPped up for download)
SCSILEVL.DIS - The original version disassembled

IBM made three different families of non-RAID Micro Channel SCSI controllers, mainly distinguished by the microcontroller or microprocessor of the circuit that controlled the SCSI bus. Even though some of the controllers could use the same microcode firmware, I have separated them by how I see those series laid out. The functionality among the families is largely the same, with the members having similar capabilities.

I don't profess to know what the different microcode versions added or fixed, but it is helpful to know if there is a later version for an upgrade (I will have some microcode images of the non-Flash series up soon so you can burn your own EPROMs if you have the equipment). Generally, it is advised to have the latest firmware possible. I have charted all the versions I have found so far. If you have an unlisted version or one marked as "Unknown", please notify me to add it.


8032-based SCSI Controllers

Based on the Intel-designed 8032 microcontroller. It is "Narrow" SCSI able to do a 5 Mbps transfer rate. All models of this series have no controller cache. The microcode is on a single 64Kx8 EPROM (except for the P75 planar). When the series was renumbered to version 02 and 03, it supports the SCSI-2 command set.

EPROM µCode © Date Location
64F1368 0Fh/15d 1989 ZM5 of Tribble, FRU 15F6561/85F0002
79F3212 0Fh/15d 1990 P75 planar "µCode" (32Kx8 OTP ROM)
64F5801 10h/16d 1990 ZM5 of Tribble, FRU 15F6561/85F0002
84F8233 12h/18d 1990 ZM5 of Tribble, FRU 15F6561/85F0002
84F8233 12h/18d None U4 of Short SCSI A/16 (SIP), FRU 07G3169
10G7174 13h/19d 1990 ZM5 of Tribble, FRU 15F6561/85F0002
41G9974 14h/20d 1992 ZM5 of Tribble, FRU 15F6561/85F0002
54G1801 25h/37d Unknown U5 of Short SCSI /A (A/16), FRU 66G1080
54G1800 26h/38d 1993 U5 of Short SCSI /A (A/16), FRU 66G1080
39G3313 02h/02d 1992 U22 on 9556/9557 planar
92F1211 03h/03d 1990 U36 on 8556/8557 planar
39G6419 03h/03d 1992 U22 on 9556/9557 planar
49G2704 03h/03d 1992 U3 on Thinkpad 700/700C/720/720C 3550-002 planar, FRU 49G2667


80188-based SCSI Controllers

Based on the Intel-designed 80188 microprocessor. It is "Narrow" SCSI able to do a 5Mbps transfer rate. Most models of this series have a base 512 KB controller cache, some expandable to 2 MB using proprietary IBM SIMMs. The microcode is on a single 64Kx8 EPROM.

EPROM µCode © Date Location
64F1333 Unknown Unknown U47 of "Old" Spock, FRU 84F8149
33F5546 07h/07d 1988, 1989 U47 of "Newer" Spock, FRU 85F0063
57F2423 08h/08d 1989 U43 of Gearbox 800 Drives Module
57F2716 09h/09d 1990 U43 of Gearbox 800 Drives Module
64F5984 09h/09d 1990 U47 of "Old" Spock, FRU 84F8149
64F5984 09h/09d None U10 of 2/3 Length SCSI A/32 w/ Cache (50 pin), FRU 95F4488
10G4890 25h/37d 1991 U47 of Spock Prime, FRU 85F0063
10G4890 25h/37d None U12 of Short SCSI A/32 w/ Cache (DIP Term.), FRU 35G2818
10G4890 25h/37d None U9 of Long SCSI 32/A w/ Cache and 2.5" HD, FRU 35G3785
10G4891 25h/37d None U12 of Short SCSI A/32 w/ Cache (SIP Term.), FRU 07G3063
39G2066 25h/37d 1992 U20 of 9576/9577 Bermuda planar
39G2066 25h/37d 1992 U51 of 9585 'X' planar
61G2976 26h/38d 1993 U47 of Spock Prime, FRU 85F0063


80186-based SCSI Controllers

Based on the Intel-designed 80186 microprocessor. It is "Fast/Wide" SCSI able to do a 20 Mbps transfer rate. All models of this series have no controller cache. The microcode is on two Flash 32Kx8 chips able to be upgraded with software.

REV71UPD.EXE - SCSI-2 Fast/Wide Firmware Rev 7.1
corv77.EXE - SCSI-2 Fast/Wide Firmware Rev 7.7

Flash µCode © Date Location
61G3929/30 57h/87d 1993 U1 & U2 of Corvette, FRU 92F0160
61G3929/30 57h/87d 1993 U139 & U140 of 9585 'K' or 'N' planar
61G3929/30 58h/88d 1993 U1 & U2 of Corvette, FRU 92F0160
61G3929/30 58h/88d 1993 U139 & U140 of 9585 'K' or 'N' planar
61G3929/30 58h/88d 1993 U1 & U2 of Diff. F/W or RS/6K "4-6", FRU 11H3599 or 11H7660
61G3929/30 71h/113d 1993 U1 & U2 of Corvette, FRU 92F0160
61G3929/30 71h/113d 1993 U139 & U140 of 9585 'K' or 'N' planar
61G3929/30 71h/113d 1993 U1 & U2 of Diff. F/W or RS/6K "4-6", FRU 11H3599 or 11H7660
61G3929/30 73h/115d Unknown U1 & U2 of Diff. F/W or RS/6K "4-6", FRU 11H3599 or 11H7660
61G3929/30 74h/116d N/A U1 & U2 of RS/6K "4-7" Corvette, FRU 11H3600
61G3929/30 74h/116d N/A U1 & U2 of Diff. F/W or RS/6K "4-6", FRU 11H3599 or 11H7660
61G3929/30 75h/117d 12/97 U1 & U2 of RS/6K "4-7" Corvette, FRU 93H8814
61G3929/30 77h/119d 1994 U1 & U2 of Corvette, FRU 92F0160
61G3929/30 77h/119d 1994 U139 & U140 of 9585 'K' or 'N' planar
61G3929/30 77h/119d 1994 U1 & U2 of Diff. F/W or RS/6K "4-6", FRU 11H3599 or 11H7660
88G1094/95 C5h/197d Unknown U1 & U2 of Enh. Diff. F/W or RS/6K "4-C", FRU 52G3380
88G1094/95 C6h/198d Unknown U1 & U2 of Enh. Diff. F/W or RS/6K "4-C", FRU 52G3380
88G1094/95 C7h/199d Unknown U1 & U2 of Enh. Diff. F/W or RS/6K "4-C", FRU 52G3380
61G3929/30 C9h/201d 1993 U1 & U2 of Corvette, FRU 92F0160
88G1094/95 C9h/201d 1995 U1 & U2 of Enh. Diff. F/W or RS/6K "4-C", FRU 52G3380

Content created and/or collected by:
Louis Ohland, Peter Wendt, David Beem, William Walsh, Tatsuo Sunagawa, Jim Shorney, Tim Clarke, Kevin Bowling, Tomáš Slavotínek, and many others.

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