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COMPUTER BITS BY JOE ELKHORNE Upgrading to a 386 - now I know what a "kludge" is! Is your computer due for upgrading but you have not known where to start? The process is fraught with pitfalls as Joe Elkhorne found to his frustration & cost. For the past couple of years, I've been perfectly happy running a modest XT compatible, an Amstrad PC20. It is perfectly adequate for simple word processing and you can't get much simpler than PC-Write 2.41. Recently, I found it necessary to provide a state-of-the-art WP document to a local book publisher. With- self-contained unit in a low-profile, plastic case. So I had the heart of a super new system and an uphill battle ahead of me. The first problem was not difficult to solve. I'd let another friend have an oscilloscope I wasn't using, again on a "pay me when you can basis". When he subsequently ac- "Right at this point, I ran into the first pitfall. Having worked with dodgy Taiwanese clones in the past, it didn't even occur to me that this board might be labelled." electronics shop in a nearby suburb. "Hi there - I need the ribbon cable that goes from a controller card to the floppy drive". The salesperson shakes her head in disgust. "They come with the controller cards". "Ifl had one, I'd not be asking for one. The thing is, I've got a secondhand card that wasn't provided with cables". "Oh yeah ... " Silence. Finally, I explicate the obvious, "So I need one". "We don't sell them". Scratching my head in perplexity, I inquire if they know who might. "You can make one yourself". "I'm game, but I need the bits. I've already got a hammer". "We sell the bits". Good, at last we're getting somewhere. At home with a bag of bits, I carefully inspect, align and assemble: ribbon cable, one, with IDC connectors, for connecting floppy drive. I do believe this technology was designed by Mr Murphy but more on this subject later. Getting it together out a platform to work on, I solicited the help of a friend with a splendid 386 system. He'd been through the learning curve with earlier versions of Windows and Word for Windows. This was an opportunity for him to show off his equipment and I was very impressed with the power of the system. When Graeme upgraded to a 486 shortly after that, he made me an offer I couldn't refuse: accept his 386 motherboard and pay him when I was abk Bonzer! There's just one trouble with upgrading the PC-20. It can't really be done. The physical architecture is not like a standard clone - it's a 64 SILICON CHIP quired a case, power supply, a CGA card and a keyboard from another person, I agreed to take these bits and pieces in lieu of cash. I think that the cashless society is already here! So, let's see where we stand. I have a 386 DX/25 motherboard with 8Mb of RAM, a "Baby" tower case with a 200W power supply which almost fits, a 360Kb 5¼-inch floppy drive, a 101key keyboard, multi-I/O card, CGA card and a PC-20 CGA monitor. Well, that's not a bad start - all the big pieces. But like any enterprise of this nature, it's always the fiddly bits that are a hassle. Fortunately, there was a discount Now my mate Rob had not only brought one case and power supply, which he was kind enough to fit, but had also mounted an old XT board in it expressly for the purpose of holding the plug-in cards in place. Right at this point, I ran into the first pitfall. Having worked with dodgy Taiwanese clones in the past, it didn't even occur to me that this board might be labelled. I looked at the mass of front panel wiring and pulled all the little connectors off without a second thought. Getting the XT board out involved compressing the nylon support posts - and holding your jaw right. Only after the board was out, in the clear light of day, did I notice that all the appropriate points were clearly stencilled. Twenty-twenty hindsight is a wondrous thing. Fitting the 386 motherboard into the case was not difficult- a couple of the nylon support posts had to be moved. But there weren't quite enough of them and some plastic from the junkbox provided additional support at a non-critical point. Nor was the power connection a problem. There's only a couple of possibilities because they're keyed and the recommended end-to-end position had already been marked with a felt pen. At this point, I truly regretted that the documentation for the 386 motherboard hadn't turned up. Oh, well, who needs a power LED anyway? None of the other front panel functions are critical to a fundamental test. I then planked the floppy drive on a magazine on top of the floppy mounting bracket for ease of testing. The multi-I/0 card was plugged into a convenient slot and my homemade ribbon cable joined up . The CGA card went alongside and the Amstrad monitor was set beside this "test jig", on the kitchen table. I'd already made a 5¼-inch boot disk. All that remained was throwing the power switch - and praying; not necessarily in that order! The smoke test Rob and his friend Liz turned up just at that point. If they expected a mushroom cloud and some gratuitous language, they were disappointed. =ftfflll/JIIJ= =U!l!l!- There was movement at the station. It's true the system didn't boot up initially but there did seem to be the proper start-up sequence. "Let's make sure the CMOS setup knows about the A: drive", said Rob. We did·this and a keyboard Ctrl-AltDel proved the system was responding properly. Unfortunately, though the floppy drive's LED came on, nothing else happened. We inspected the drive to make sure nothing had been whacked out of As well, I'd done a diagnostic/configuration dump, so I knew the port addresses (serial, printer) and interrupt vectors which had been successfully working. Again we fired up the unit and forced the system into the CMOS setup procedure. Golly, I wonder which of the 47 types I should call this beast? We exited the CMOS setup to have a think about things. Despite the obvious report that no C or D hard drive existed, the system booted up prop- "Rob & his friend Liz turned up at that point. If they expected a mushroom cloud and some gratuitous language, they were disappointed. There was movement at the station." shape. Everything looked all right but we wondered about the mysterious little jumpers. Just maybe, we decided, this drive was old and needed to be told, some way or another, that it was in an AT-style machine. Meanwhile, it was very frustrating being this close without actual operation. We decided to be daring and put the 40Mb hardcard into the system. I'd backed up all the files that morning, using the ARJ utility, to the existing 720Kb drive of the PC-20. Regardless of"finger trouble" - short of something really catastrophic like dropping the hardcard - I should be able to resume operation totally on the old machine. erly! Obviously, the system bus recognises the existence of the hardcard controller and acts appropriately. Well, this was exciting. At that point, we added the serial port cable and modem and called our favourite bulletin board. That effort was successful and we called it a night. No sense in pushing our luck, we decided. The following morning, just to be thorough, I proved that the parallel port worked. Now all I needed was to get a floppy working. Because of my BBS activities and the small hard drive setup, I do a lot of archiving on floppy disks. I proceeded to do more kitchen table tests - unsuccessfully. Position Vacant - Technical Writer SILICON CHIP has a position for an enthusiastic technical writer. This person will already be a frequent reader of this and other technical magazines and will probably have a number of hobby interests. Technical qualifications are not mandatory although a good background in electronics is necessary. Good writing skills are essential for this position and some familiarity with computers would be an advantage. Do you think you could do the job? You will mainly be involved in the writing and preparation of articles for this ~agazine. For example, you could be required to write the constructional article on the ~lectric fence project in this issue or the short feature article introducing the Digital Cassette Deck, after attendance at the recent Australian release. You will also have the opportunity to build simple electronic projects under supervision and you will be involved in proof reading and other activities involved in the day to day production of the magazine. The salary package is negotiable. If you think you could actively contribute to the improvement and growth of SILICON CHIP, send your application in writing to The Publisher, PO Box 139, Collaroy Plateau , NSW 2097. Applications close 21 st April, 1993. APR,L 1993 65 COMPUTER BITS - Upgrading to a 386 I tried the technical support telephone number for the drive manufacturer, only to learn that their local office was closed. It's amazing how many operations here in Melbourne have shut, with everything allegedly handled from Sydney. And not all of the companies have 008 numbers, unfortunately. supports 360Kb drives. This snippet of information was verified in the discount dealer's catalog. Off to the local bloke again. "Hi, it's me again. I need a high density drive, a three-and-a-half, please". This time, there's a bloke at the counter. He rummages around looking for said unit while I go over to the display and find the catalog An old adage number for the cheap controller. HavThen I recalled the old adage, "when ing perused the catalog thoroughly all else fails, read the book" and re- over morning coffee, I know there are membered that I'd seen a book on PC several to choose from. All I need, I've architecture and hardwar~ technical told myself, is one floppy and this details. I made a special trip to the controller is linkable for two drives of city. In fact, I found several compre- the same type, from 360Kb to 1.44Mb. "That's not the right controller", hensive reference books to choose from. Selecting one, I flipped to the , says the clerk. "I know that there's no table of contents and went straight to doco with it. I can see through the the chapter on floppy drives. plastic wrap. But see these links? And Right. One of the lurks is the old note the description in your catalog? cable twist - oops! - and the link for Now, can I be wrong? I've been wrong DR1 on the floppy drive itself. Fair before". He decides that maybe I'm not enough, my mistake: the straightthrough connection as I'd made the wrong and rings up the sale. I decide cable is actually the B: drive position. I'm on to a good thing because there's Hey, suppose all this fiddling has two drive cables in the packet. Wow! "The young woman takes the drive straight to one of the demo machines, kills the power, pops the top, pulls the cables and swaps it into the system It fires up, and works beautifully." done something to the drive itself? Ah, substitution test. No, I don't have a second floppy but I can put it back on the PC-20. Yes, it works. Well, the old process of elimination is one of the tried-and-true ways of troubleshooting. Now, at least, I have one less variable to worry about. Funny thing though, when I put it back in the 386, not even the LED would come on. Fiddle, wiggle, oops, the motor started. Could it be? Now I'm suspecting my cable but I don't have a spare. At this point, I'm telling myself that a 360Kb drive is old-hat anyway! I quickly justify the need for a 1.44Mb drive. Bewdy! Oh, and a controller of course, since the multi-1/O card only 66 SILICON CHIP And I've got the mounting adaptor bracket kit so I can install this beauty permanently. Racing home, I pessimistically decide to test it externally before I bolt it in place. I swap controllers, checking the stencilling on the new and deciding that yes, it does say it's set for 1.44Mb. I swap controllers, attach one of the new cables to the high-density drive and turn it on. It doesn't go. Oh, yes - I've got a formatted 1.44Mb disc in place. Well, at least the packet said they were. The LED was on, though. Unfortunately, it's always on. I wonder what will happen on the PC-20? I look at its manual. Yes ... DRIVEPARM should work. It's kitchen table time again. I'm really wondering if I could borrow a second monitor from somewhere; I'm tired of carrying the one-and-only back and forth. Never mind. Hey, power up and look at that: the system recognises there's a controller card in the slot and even knows what size it handles. But, oh dear. Why doesn't the drive work? Oh dear, what's happened now? Why is my boot disk in the A: drive corrupt? I go through every permutation that's possible. The mounting adaptor kit came with a 3½ to 5¼ ribbon cable adaptor and a power adaptor to match the usual power supply connector. By flicking a switch in the PC20, I can tell the system that the outboard drive is the A: drive. The power adaptor lets me try the edge connector on the cable, rather than the dualrow miniature connector which would be more commonly used. Aha! As I'm about to put cable to connector, something rather suspicious catches my eye. I look closely and discover, deep inside the 5¼ edge connector, a smashed contact shorting across from one side to the other. Why hadn't I seen this before? Because I was using the smaller and more appropriate connector. Score: cables 2; Joseph 0. I throw the thing aside with several rude words and find the other new cable. Double checking the "repair and upgrade" book, I confirm my understanding of the A position and B position. Now I go back to the 386 and try it. It still doesn't work! As soon as I walk into the discount electronics store, I get the impression that I've worn out my welcome. Even the laying on of plastic money might not help. I state the problem: can't get the little drive to work in two machines! The young woman is knowledgeable - she takes the drive straight to one of the demo machines, kills the power, pops the top, pulls the cables, and swaps it into the system. It fires up and works beautifully. Fair enough. Whatever is wrong is my problem, not theirs. Having seen the little drive work, I believe I can trust it. Unfortunately, back home, it still doesn't want to respond. All I'm getting is "Not Ready Error Reading Drive A (Abort, Retry, Fail)". Can it perhaps be the controller? Hey, if I'd bought the next model up, I'd be able to mix and match, put the 360Kb onto it to prove the system to that point, without any hassle. Why don't we take another drive today? They're definitely not overjoyed to see me again so soon but are more than happy to swap/upgrade. A little more money for them and maybe it will get me out of their hair. This new board is switch-selectable for four drives, independently. How can I go wrong? I start with a known the 360Kb drive - and prove that the controller and the system are happy to work together. I swap over to the 1.44Mb drive but no go. How weird can you get? Yet another foul-up Nonetheless, I'm happier with this co·n troller since there is some documentation. In fact, just as a second test, I even drop it into the expansion slot on the PC-20 and the system boots up and recognises the various switch configurations. Incidentally, in the process of all this drive testing, I've been experimenting with other facets of operation. I discover "Yet Another Foul Up" - the serial port sometimes locks up when using Telix. I spend an hour or so with a breakout box, trying to figure out what and why. Finally, I disable the XON/XOF (software) flow control, dropping back to DTR (hardware) control, and that seems to help. The original RS-232 port was a true 25-pin connection. The flying lead from the card to the backplane connector is skimpier. This needs further investigation at a later stage. Meanwhile, it's back to the drive anomalies. I'm starting to feel paranoid and begin with what should be a known working situation: the 360Kb as B-drive on multi I/O. Yes, that's OK. Now I fit the 4-way controller, set the DIP switches appropriately, reboot, and the system CMOS recognises the existence of the 360Kb drive without intervention. I do DIR B: and that's fine. Everything working. Though this might seem laborious, eliminating variables and starting with a known fully working situation at the immediate moment is a good, if pessimistic, plan. I add A: (1.44) without power, of course, and re-start the system. B: now does not work- Not Ready Error Reading Drive (Abort, Retry, Fail). Hmm, let's disconnect the ribbon cable from B and try A only, as A. Reset, CMOS COMING NEXT MONTH Remote Volume Control This project will let you adjust the volume & balance of your hifi stereo system from the comfort of your lounge chair. It's based on a dedicated microprocessor chip to simplify the circuitry and to make construction as easy as possible. It won't degrade the sound quality either, thanks to excellent specifications. Full details in the June 1993 issue. Woofer Stopper (or Dog De-Barker) Do you have trouble with barking dogs? If so, this project could be the answer to your prayers. It produces a retaliatory high-energy supersonic tone which discomforts the dogs and discourages further barking. After a few weeks of use, the dogs will be miraculously quiet. check, OK, reboot, Not Ready Error Reading Drive A. Well, all I know for certain is that the 360Kb drive on its own works. Can there be something incompatible about the 1.44Mb drive and both of my computers? Later, a call to Amstrad's technical support section elucidates the information that the PC20 will not support a high density drive, even with an external controller. "Why is the information in the manual so ambiguous?" "It's there for completeness only ... " "Groan". This was the day I went back to the PC92 show for the second time. I bought Windows 3 .1 for $95 (on 1. 2Mb which is all they had) and leaving there, went to "the local blokes" and bought a 1.2Mb drive. I raced home with all the goodies. Using the new 1.2Mb drive only and the 4-way controller set as A=l.2 and B=360, at last I had a working highdensity drive! Finally, I reset the controller for B=l.44, cobbled the thing into place and was rewarded with a proper start-up sequence. The A: drive was still perfectly happy. Asking the B: drive anything, however, still gave me a DOS error - but the LED was coming on and going off. What the heck: Format B: /s. Oh, wow! It's doing something. Presumably, somewhere along the line, the actual disk I'd been using was corrupted. I spend the afternoon and evening doing real computer things with two working high-density drives. Joy! The following morning, I turn the computer on -and the B: drive refuses to work! The LED comes on and goes off, but again I'm getting DOS error messages. The final lurk turns out to be a dicky power adaptor for the 1.44Mb drive and the forceful application of a pair of visegrip pliers ensures that the intermittent connection will never happen again. Everyt,hing now gets bolted back into place and re-tested. Two months later, the fundamental hardware is still reliable - at least at the DOS level. I've now embarked on a learning curve for Windows 3.1, DOS 5.0, Word for Windows 2 and the mysteries and frustrations of printer drivers or the lack thereof. But that's a story for next month's issue. SC APRIL 1993 67