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Lt. Kernal — Xetec and Fiscal Host Adapters

Xetec Lt. Kernal subsystem, with both host adapter types.

Lt. Kernal History

The ancestry of Fiscal Information's Lt. Kernal hard drive subsystem can be traced back to 1983, and is as much a story of the fortunes of Commodore Business Machines (CBM) and the changes in the larger spectrum of business computing as it is an account of the Lt. Kernal itself.

The early 1980s were an exciting period in the development of home computers.  In late 1982, Commodore had introduced the remarkable C-64, and by the end of 1983, the computer had become an unqualified success.  By mid-1984, the C-64 had crushed its competition and was well on its way to becoming the best selling computer model of all time.  However, there was a problem.  Despite its advanced features, the computer was hobbled by the notoriously unreliable and feeble-performing 1541 floppy disk drive, the most commonly used mass data storage accessory.  Not only was the 1541 slow and untrustworthy, it could only store 170 kilobytes per disk, which for many users, simply wasn't enough.

For those seeking higher capacity and better performance, there were a few alternatives available in Commodore's IEEE-488 disk drives, such as the 8250 and SFD-1001 one megabyte floppy units, and the 9060 and 9090 hard drives.  Connecting any of these to the C-64 required the use of an IEEE-488 bus adapter cartridge, which was not entirely transparent to the rest of the system.  Software compatibility problems would arise and therefore the IEEE-488 route was often not satisfactory.  This rapidly became an issue for the steadily-increasing number of C-64 owners who were running bulletin board systems (BBS).

Although the 9060 and 9090 hard drives were particularly tempting with their high (for the time) storage capacity, they proved to be absurdly slow and grossly unreliable, in some cases literally burning up during operation.  A better mass storage solution was needed, and the Lt. Kernal was the pioneering hard drive system that met this need.

Lt. Kernal to the Rescue

Fiscal Information's Lt. Kernal subsystem was conceived in late 1983, prototyped in 1984 and went on the market in early 1985.  In 1986, Xetec, Inc. was given manufacturing, distribution and support rights, at which time a cost-reduced version, illustrated above, went into production (such units have a serial number beginning with 8700 and use the host adapter shown on the left—the older Fiscal-manufactured host adapter is on the right).  Other than detail improvements to reduce cost and adapt the system to the C-128DCR, the Lt. Kernal hardware design from 1987 onward was essentially unchanged.  However, the DOS underwent a number of revisions, starting with version 6.0 in 1986 and culminating in version 7.2 in 1990.

The Lt. Kernal had no competitors when it came to the market in 1985.  In fact, it would be several years before anyone else developed anything that was remotely comparable.  Competition got into the picture only when it became clear that there was a sizable demand for high capacity mass storage for the C-64 and C-128.  With the Lt. Kernal on the market, Commodore ceased development of its nascent HD10 hard drive but accelerated development of the 1581 floppy drive.  Ironically, it was the availability of the Lt. Kernal that gave impetus to the 1581's development, as the Lt. Kernal's FASTCOPY file archiver included special features that could exploit the 1581's storage capacity and burst mode capabilities.  In the latter 1980s, competition arrived in the form of less capable but lower cost systems developed by ICT and CMD, among others.  Only the CMD systems remain today.

Accidental Hard Drive System

The Lt. Kernal project got off to an accidental start when Roy Southwick, one of the two developers of the system, acquired a C-64 and 1541 floppy drive for his son in 1983.  Roy, being the chief software engineer at Fiscal Information, Inc. at the time, was accustomed working with the high-powered and costly Point 4 minicomputer systems that his company marketed to its medical information systems client base, machines that were capable of loading files from disk at the rate of several megabytes per second.  Needless to say, Roy found the 1541's performance to be extremely dismal in comparison, so much so that he called over his colleague, hardware engineer Lloyd Sponenburgh, and gesturing toward the C-64, jokingly asked a momentous question.

"Do you think we could hang a hard disk on that thing?"

Thus was born the idea of the Lt. Kernal.

Both men eagerly launched themselves into the project, which proved to be far more complicated than either imagined.  Much of the difficulty was due to the fact that CBM drives like the 1541 were "intelligent" and, as a result, there were no provisions in the C-64 architecture to control a disk drive.  Therefore, a DOS had to be developed that could run in the C-64 without interfering with normal computer operation.  It seemed as though there were endless hardware and software issues to resolve.  In fact, the two came very close at one point to abandoning their efforts.  When it became apparent that the project could succeed, Fiscal Information assisted with funding and access to specialized equipment that could be used to resolve hardware problems.  Lloyd and Roy pressed onward and as the end of 1984 approached, they had working hardware.  However, they weren't done.

The Point 4 minicomputers sold by Fiscal were run by the IRIS operating system, which included many advanced features for efficiently managing and utilizing high capacity mass storage.  C-64 users, on the other hand, had little more than the old DOS wedge for disk management.  So Lloyd and Roy decided to "borrow" some IRIS features and scale them down to fit the Lt. Kernal.  The result was, among other things, the ability to run a program by merely typing its name, as well as the ability to mass-copy and relocate files with easy-to-use commands previously unknown in the C-64 environment.  Also introduced was a never-before seen feature in the microcomputer world: the keyed-index random access method, which made it practical to implement large relational databases on the C-64.  The two men had turned the C-64 into a clone of the Point 4 system, but in a form small enough to fit on an ordinary desk.

Smart Choices

The Lt. Kernal's public debut came at a meeting of the Daytona Beach (Florida) Area Commodore Users' Group just before Christmas in 1984.  Commodore notables who were in attendance, including the late Jim Butterfield, CBM public-relations manager Pete Bazcor, and Margaret Morabito, "RUN" magazine's technical editor, could scarcely believe what they were seeing.  Here was the modest, eight bit C-64, devoid of its 1541 drive, acting like a 20,000 dollar, 16 bit minicomputer and loading files at a jaw-dropping rate!  Phrases like "amazing," "unbelievable" and "blinding speed" were frequently heard.  Everyone who witnessed that demonstration was dumbfounded.

Much of the astonishment at that debut stemmed from a design choice that was made early on by Lloyd and Roy.  The Point 4 minicomputer interfaced its hard drives to the main system through a high speed, parallel bus architecture known as SASI (Shugart Associates System Interface).  Invented in 1979 by computer storage pioneer, Dr. Alan Shugart (1930-2006), SASI was capable of data transfer rates of as much as five megabytes per second.  Lloyd and Roy had implemented a scaled-down form of SASI to connect the hard drive to the C-64, a move that proved without a doubt key to the success of the system.

Even with a scaled-down SASI running on a one megahertz, eight bit machine, the data transfer rate was still an amazing 38 kilobytes per second, 125 times faster than the speed of the Commodore serial bus.  The resulting performance was more than sufficient to support DOS features that would not have otherwise been practical.  Also important was the fact that the American National Standards Institute (ANSI) was in the process of defining SASI as a computer industry standard, which meant that the Lt. Kernal's interface would be future-proofed and would be adaptable to new storage technology as it became available.

Lt. Kernal Development

When the Lt. Kernal went into production in early 1985, it was equipped with one 5-1/4 inch, full-height, 10 megabyte, ST-506 MFM (Modified Frequency Modulation) hard drive mechanism mated to a programmable OMTI 5300 intelligent SASI controller, the latter a standard minicomputer component in common use at the time.  Along with the first design host adapter (illustrated above, right), the system sold for approximately 1,500 dollars, about six times the cost of a C-64 at the time.  The 10 megabyte capacity was equal to approximately 58 formatted 1541 disks.

The OMTI controller could interface to one or two ST-506 drives, as well as a QIC-02 quarter inch streaming cartridge tape drive.  As the OMTI controller had on-board intelligence, it was possible to program it to copy data directly between disk and tape at the rate of about 150 kilobytes per second, without host computer intervention.  Fiscal exploited this capability to offer a high speed file backup option, at an additional cost of 1,500 dollars.  Needless to say, it wasn't a big seller at that price.

In 1986, ANSI completed the process of defining SASI as industry standard X3.131-1986 and named it SCSI to highlight the fact that is was not a vendor-specific bus architecture.  The introduction of SCSI to the computing universe proved to be a significant point of transition in the development of the Lt. Kernal, as hard drive manufacturers responded by producing hardware designed around the features of the new bus standard.  This new generation of "embedded controller" drives, which incorporated an onboard intelligent SCSI controller as part of the hardware, was less costly to manufacture, reduced system complexity and improved overall reliability.

Following the formalization of SCSI, Fiscal modified the Lt. Kernal's design to work with the new drives, resulting in a substantial reduction in the price of the system.  The standard drive mechanism was now a half-height, embedded controller unit, allowing the use of a smaller and more stylish drive enclosure, and the standard capacity had been increased to 20 megabytes.  40 megabytes was an extra-cost option (40 megabyte drives continued to be ST-506 units for some time, but now used a less expensive OMTI 3100 controller that did not support a tape drive).  Later systems were fitted with half height, 3-1/2 inch drives, further reducing cost, improving performance and increasing reliability.

Hardware changes were also made to the host adapter to eliminate cost, as well as to support the C-128 (introduced in late 1985), and to add a new feature called ICQUB (Image Capture Quick Utility Backup), which could capture and save copy-protected software to the hard drive.  A multiplexer was developed to allow up to 16 computers to share a single drive.  The redesigned system's retail price was now 899 dollars for the basic C-64 version and 949 dollars for the C-128 version.  Discounts were offered in some cases, and sales started to pick up.

Along with the hardware changes, the already-powerful Lt. Kernal DOS was enhanced and modified to work with the embedded controller drives, while still remaining compatible with the older units fitted with OMTI controllers.  The ability to support CP/M on the C-128 was introduced, producing what was arguably the fastest CP/M system ever.  Fiscal continuously updated the DOS to keep pace with user requests, often making upgrades available at little or no charge to registered Lt. Kernal owners.  The final version of the DOS, 7.2, which was released in late 1990, included many advanced features, such as the ability to create custom system commands or aliases for existing commands, as well as new tools geared to custom software development and support of specialized file formats.  By the end of 1990, the Lt. Kernal had reached its final stage of development.

The Final Years

The late 1980s and early 1990s were a time of ascending PC dominance and a gradual fading-away of the hardware hacker spirit that had made possible a system such as the Lt. Kernal.  By 1990, Commodore was rapidly sliding toward bankruptcy, unable to turn a profit selling the Amiga, into which they had invested so much.  Although the C-64C was still in production and a next-generation version dubbed the C-65 was in prototype, eight bit hardware was heading toward a dead end.  Home users were now buying PCs running MS-DOS and, increasingly, Microsoft Windows. PCs didn't lend themselves to recreational hacking and programming.  The handwriting was on the wall: machines like the C-64 were rapidly going out of style and money could no longer be made selling accessories for them, especially expensive accessories like the Lt. Kernal.  Recognizing all these changes, Fiscal and Xetec decided it was time to close down production and move on.  The Lt. Kernal was discontinued in December 1991 and all support ceased one year later.

Fiscal Information continued on for a few more years in their primary role of medical systems technology provider, as they had been doing since they opened their doors in 1971.  Xetec continued to produce Commodore accessories until 1995, at which time they closed down and liquidated their assets.  Two years latter, Reynolds and Reynolds, a fortune 1000 company that was also in the medical systems business, acquired the stock and assets of Fiscal, and then dismissed most of the staff, including Lt. Kernal designers Lloyd Sponenburgh and Roy Southwick.  In a final death blow, Fiscal was formally dissolved as a corporation and ceased to exist.  Of course, as is well known, Commodore, wallowing in debt and unable to renegotiate outstanding notes that were due, collapsed into bankruptcy in 1994 and was liquidated.

Lt. Kernal Usage and Limitations

So, who puchased the Lt. Kernal?  The system was marketed to small businesses, software developers and, of course, BBS SysOps, who enjoyed the high storage capacity and rapid performance.  The largest known single application of the Lt. Kernal system was at a truck leasing and billing company in the Chicago area, in which eleven C-128D workstations and one C-64 were multiplexed to an 80 megabyte Lt. Kernal, the C-64 acting as a print spooler.  Many systems did duty in a wide variety of small businesses.  Home users who enjoyed recreational programming bought the Lt. Kernal for its performance and storage capacity.  Unfortunately, any records related to the sales of the system have been lost, so the total number of systems that were shipped presumably will never be known.

Estimates around 1990 placed the Lt. Kernal market share at about 22 to 25 percent of the total eight bit Commodore hard drive market.  This share started to slip once Creative Micro Design (CMD) released their less-capable and less-expensive hard drive system.  There was little question that price became a significant factor once CMD came on the scene, as the Lt. Kernal was substantially more expensive than a CMD unit with the same capacity.  However, as in almost everything else, the buyer got only what he or she paid for.  The lower price of the CMD drive was the result of having an inferior interface design that relied on the Commodore serial bus, and not having the powerful operating system functions that were native to the Lt. Kernal DOS.

Ironically, the technical complexity that made the Lt. Kernal perform so well may have also worked against it.  Installing the system required opening up the computer to make connections, something that was not an acceptable procedure for some purchasers.  Maintaining serial interface burst mode operation in the C-128 and C-128D required a modification to the main circuit board that involved soldering a wire and cutting a chip pin, which was more than most would-be owners wished to do.  The Lt. Kernal DOS was somewhat intimidating to novice users who had little or no command line experience.  There were many commands to learn, some of which could be destructive if improperly used.  Learning how to get the most from the Lt. Kernal required an investment in time to read about and experiment with the DOS's many features.  Often, users simply weren't willing to make that investment.

Although Fiscal took great pains to make the Lt. Kernal as transparent as possible to the C-64 and C-128 kernal, it was not 100 percent successful in that regard, nor could it be.  Some programs would not be run because they made improper assumptions about the type of mass storage in use.  For example, GEOS, a popular windowing operating system that ran on both the C-64 and C-128, would not be run on a Lt. Kernal system due to the way the GEOS kernel interacted with the hardware.

The Lt. Kernal DOS interaction with the Commodore kernal demanded the use of a much more disciplined approach to software development than was often found in the eight bit Commodore world.  Complaints of incompatibility were most often traced to amateurish programming techniques, as well as a lack of understand about the way the Lt. Kernal behaved.  Incompatibility was often encountered in attempting to get some sloppily-designed BBS packages to run on the system (two in particular, C-Net and Image, a C-Net derivative, were particularly egregious examples—arguably the worst cases of spaghetti code ever written by anyone).  Other compatibility issues developed because amateur assembly language programmers would bypass the kernal jump table (contrary to both Commodore's and Fiscal's instructions) and directly call kernal ROM subroutines.  When the system crashed after a call to a now-relocated or modified ROM function, it was always blamed on the Lt. Kernal, not the programmer's ignorance.


In the final analysis, the Lt. Kernal was a success by any measure.  Although it never enjoyed the sales of its less-capable competitors, it was the first such system to bring high performance mass storage to the eight bit Commodore line.  It opened up a whole world of programming possibilities that were previously unknown to Commodore programmers.  And, it did something that its competitors could not do: make a modest, eight bit computer designed for home use perform like a multiuser minicomputer costing thousands more.

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