Copyright 1987 by Sheldon Leemon and AmigaForum ----------------------------------------------- The Sidecar Arrives--Sort Of When the Sidecar was first shown at Spring Comdex in April of '86, Commodore was saying that it would be available for sale within a few months, and that dealers would be receiving demo units by May. Eight months later, as the year drew to a close, it looked like '86 might not be the year of the Sidecar after all. But just about the time of the World of Commodore show in Toronto, a few demo units finally began to make their way into dealers hands, just as finished models went on sale in Germany and Canada. The following report is based on the little hands-on experience I've been able to gather since then with both a German and a Canadian Sidecar. For those Amiga owners who have spent the last six months on the moon, the Sidecar is an IBM PC add-on for your Amiga. Unlike the Transformer, Commodore-Amiga's noble, flawed experiment with software-only emulation, the Sidecar isn't just an IBM PC emulator, it's an actual PC that plugs right into the side of your Amiga. It comes with an 8088 processor running at the standard (slow) 4.77MHz speed, a socket for an 8087 math coprocessor, 256K of PC RAM, expandable to 512K on the motherboard, one built-in 5 1/4" 360K disk drive, 3 full-sized IBM type expansion slots, and the Phoenix BIOS, an operating system famed for its close compatibility with IBM's. The box is physically a little more than half as wide as the Amiga itself, a couple of inches higher, and a couple inches deeper. Though it plugs into the expansion port on the Amiga's right side, it's almost a complete stand-alone PC. The IBM applications it runs are loaded off the Sidecar disk drive into Sidecar RAM, and are executed by the Sidecar 8088 processor. The machine depends on the Amiga only for its screen display, which the Amiga manages in a window on the Amiga monitor. It can also use the Amiga serial and parallel ports, though in order to use the printer port as LPT1:, you've got to run a program that assigns it temporarily to the IBM's exclusive use. Note that except for a hard drive, the Sidecar's disk drives are completely separate from the Amiga drives. This means that you can't use the Sidecar's internal drive for storage of Amiga programs (though the Amiga can mount the IBM floppies as a device so it can COPY text files directly from IBM format). Any additional drives that you hook up to the Sidecar, 5.25" or 3.5", become IBM drives. This means that you can use your additional external 3.5" as df1: or B:, but not both at the same time. The question most often heard is, what do we need with a PC clone for the Amiga? After all, many of us got the Amiga in order to ESCAPE the boredom brought on by IBM and its Asian imitators. And even for those poor souls who need IBM compatibility due to job demands, etc., why the Sidecar? Why shouldn't the Amiga owner who wants PC compatibility just buy a separate clone and have two computers? After all, the price of the Sidecar (which is reputed to be anywhere from $750 to $1000, since Commodore hasn't released pricing information as of yet) is about as much as the cheapest of imported clones. There are a couple of answers to this. First, as an Amiga peripheral, the PC is not quite so bad. If it starts to annoy you, you can always shrink its display down to a little teeny window in the corner of the Amiga display. Make a little, teeny Lotus 1-23 display that shows 2 rows by 3 columns. This really puts the PC into perspective, and in its place. But seriously, another reason for wanting a Sidecar is that its addition to your Amiga system actually gives you a little more than you would get by having two separate computers. Since the two computers are connected together, and can communicate with one another, each can enhance the performance of the other. The best example of this is the Sidecar's ability to share a hard disk with the Amiga. One of the first things we did with the Sidecar was to plug in a 21 Megabyte hard disk on a card into one of the expansion slots. Setting up the drive was a somewhat involved process (mostly because there were three different sets of instructions), but well worth it. Our hard disk card came with the "deep formatting" already done, so the next step was partitioning the drive. This involves using system software programs to logically divide the hard disk into sections, one of which can be used by MS/PC-DOS, and the other by AmigaDOS. First, we used the normal IBM DOS program "FDISK.COM" to create a DOS partition. Using this program, we allocated about 12 Megabytes of hard disk storage to the IBM side. Next, we ran a similar PC-DOS program called "ADISK.COM", which comes on a 5 1/4" disk with the Sidecar. This one was written by Commodore, and it functions almost identically to FDISK, but creates Amiga partitions on the disk. You can create up to four Amiga partitions on the hard disk using this program. We opted to put the whole remaining 9 Megabytes in one big Amiga partition. The next step was to format the disks. Again, the DOS partition of the hard drive was formatted just as any PC hard drive would be, by using the DOS command "FORMAT C:". The Amiga partition, however, was formatted with a program on the Amiga side called DJFormat, found on the Amiga Sidecar 3.5" system disk. This program refers to the AmigaDOS partitions as devices JH0:-JH3:, not as DH0: like normal Amiga hard drives. The "j" stands for Janus, which is the Amiga Operating System's name for the Sidecar. Janus was the Roman god of beginnings and endings, and is usually pictured as having two faces, one in front and the other in back of his head, so that he's able to look in both directions at once. At the beginning of each session in which you wish to access the Sidecar hard disk from the Amiga side, you've got to run program on the PC side called "IH.COM", which inserts the Amiga hard disk handler into the PC interrupt handler, and a program on the Amiga side named "DJMount", which mounts the hard disk as an AmigaDOS device . Since the Sidecar PC can boot from the hard disk, you can run the PC program automatically by putting the command "IH" in the "autoexec.bat" file, which is IBM's version of "s:startup-sequence". And by editing the "startup-sequence" file on your Amiga boot disk, you can mount the hard disk automatically each time the Amiga boots up. Remember, though, since the hard drive has to be mounted before it can be read, there's no way to boot the Amiga from the hard disk after your used Kickstart. Using the hard disk on the Amiga is not not blindingly fast, but it's still a lot faster than floppies. Amiga BASIC, which loads in 10 seconds from the floppy, came up in 5 from the hard disk, about as fast the Micro Forge hard disk for the Amiga. And this was a slow hard disk card (about 85 milliseconds access time)--faster ones are available. Moreover, there are rumors floating around Commodore and the Amiga community that Tim King, the person at Metacomco most responsible for AmigaDOS (some might even say, the one to blame), has a way to optimize the DOS so as to speed up hard disk access four times! But even without taking into consideration the gains in speed realized by adding a hard disk, the convenience of having all your system files at hand is a real blessing. Once you boot up the hard disk, your startup-sequence files can assign all of the system directories (c:, l:, libs:, s:, devs:, and fonts:) to the hard disk, so that all of them are always accessible. Just think of it--never seeing the message "Please insert volume Workbench in any drive" again! While the Sidecar adds a cheap hard disk capability to the Amiga, the Amiga adds small, but nice, enhancements to the PC side. The Amiga handles the Sidecar display like any other Amiga task. The display can run in a window, with horizontal or vertical scroll bars. But if you double-click in this window, size it out to full screen size, or use the menu item provided, it turns into a full-screen borderless display that looks just like a PC (complete with its own PC character font). Since the Amiga is handling the display, you aren't limited to the 16 colors of the IBM monitor. A menu on the PC window allows you to select anywhere from 2 to 16 colors for the PC display, and to choose those colors from any of the 4096 offered by the Amiga. Although two-color screens are updated the fastest, even the 16-color screens seem to scroll as quickly as the standard PC screen (in fact, using benchmark programs all Sidecar operations checked out at full PC speed). If you choose a four-color screen, the PC window appears on the Workbench screen, where it can overlap other Amiga task windows. With any other color resolution, the display appears on its own custom screen. One neat offshoot of this is that when an IBM program switches to 40-column mode while located on the Workbench screen, it only takes up half the width of the screen, since the Workbench never goes into 40-column (320 pixels across) mode. Once I even got the IBM version of Flight Simulator to display on the left half of the Workbench screen along with Amiga programs on the right half. Of course, you can also get 40-column programs to display "correctly" by putting the PC display on its own screen. The Amiga provides emulation of both the monochrome and color displays, though only one can be active at a time. In addition, you can open up multiple windows on the same display. This allows you to bring up part of a spreadsheet display, "freeze" it in one window, and look at another part of the spreadsheet in another window at the same time. Of course, putting the Sidecar display on the Amiga doesn't make the PC multitask--as good as the Amiga is, it can't work miracles. Having the PC display in an Amiga window provides all kinds of advantages. For one thing, if the PC display is on the Workbench screen, you can overlap Amiga task windows on top of it, to provide Sidekick type accessories. For another, the PC display becomes part of the Amiga display. That means that anything shown on the PC display can be dumped into IFF graphics files on the Amiga side using Grabbit or some other similar screen dump program. Not only is this an easy way to provide COLOR IBM screen dumps, but it provides an easy way to translates PC graphics to the Amiga. For example, if you bought a PC-compatible optical scanner to digitize line art for desktop publishing, you could display the resulting images on the Sidecar PC display, and then capture them to an IFF file on the Amiga side with Grabbit. I've tried it, and its like instant IFF! Despite the Sidecars many advantages, there are still a couple of question marks remaining. The first is a technical concern in the area of Amiga memory expansion. A machine like the Amiga often finds even 512K as a limitation, and this situation isn't helped by the fact that support software for the Sidecar can take away about 90K of that memory. The Sidecar has its own 256K or 512K of IBM memory on the motherboard, and you can add more IBM memory via one of the PC expansion slots. But this memory can only be used by the 8088, not by the Amiga. The obvious solution is to add a memory card between the Amiga and the Sidecar. Unfortunately, with the Sidecar model we have, this doesn't seem to work. Commodore has assured everybody that it "should" work on the ones that are actually delivered, but we can only cross our fingers on this one. Jerry Robinson of Microbotics, makers of the Starboard II memory expansion, says that the problem seems to involve the way the memory board autoconfigures. In his opinion, if you change the PAL on the memory board so that it does not autoconfigure, it should work with the Sidecar. This would mean that you would have to use the Addmem program in your startup-sequence to make the Amiga recognize the additional memory, which is no big deal, particularly if you are always mounting a hard drive card at startup also. Even if it turns out that the timing is too critical to allow anything to come between the Amiga and Sidecar, then there are other avenues to explore. One of these is expanding the memory inside the Amiga itself. A couple of expansion boards that have been announced that plug into the 68000 socket on the Amiga motherboard. These boards would allow you to add one Meg or four Meg of memory internally, along with a real-time clock. These products have not been shipped yet, but we will certainly look into them when they are available. Another route is to solder memory chips onto the existing memory chips in the Amiga "piggyback" fashion, to get another 512K in the Amiga (this mod is described in detail in a number of files in the Hardware DL). Finally, there is a socket for a 1 Meg Amiga memory expansion board in the Sidecar itself. This connector is hidden beneath the Sidecar disk drive, but since it's a custom socket, a new type of board would have to be built to fit it. Amiga plans to offer such a board, but no definite date has been given. The other concern with the Sidecar is with support and availability. Even though the unit has gotten FCC approval, Commodore does not seem to be making a big push to sell it in the States. Perhaps that's because of the price, which they can't seem to get down to the $600 level that they wanted. Perhaps, also, its because they have newer PC technology that will allow them to make the Sidecar cheaper (you'll be hearing more about that in 6 weeks, when Commodore announces new Amiga models). Whatever the reason, all Sidecars in the U.S. are currently (1/86) being brought in from West Germany or Canada. Right now, the Sidecar offers the possibility of cheap hard disks for the Amiga, with an enhanced PC thrown in almost for free (since a Sidecar with a hard disk card doesn't cost much more than an Amiga Hard disk). But since both processors can communicate with one another through shared RAM, it's possible that in the future we'll see genuine hybrid programs, that run on both processors simultaneously, or that use the Amiga for its great graphics display and the 8087 coprocessor for number crunching. Commodore already has shown an experimental program that allows you to clip text from an Amiga program and insert it into a PC program, or vice-versa. The further development of such programs would really prove the old saying that "two heads are better than one".