Fullscreen HTML5Med Res (??MB)HTML4

■ 6 SILICON CHIP If you can use a · screwdriver and follow a few simple instructions, you can build this highperformance ATcompatible computer. It uses a 12MHz ·zero wait state motherboard and is built into an attractive tower case which will save space on your desk. By GREG SWAIN .\;[ -V :'.~ j"" ',f ?\~D/.- ~ -'=. ~~~$ ·~,~-,-»,v r- -~-,~~:Iii When Electronic Solutions advertised their new 12MHz AT-compatible motherboard in our May issue, we were immediately interested. Suddenly, for just $495, you could buy a motherboard incorporating features that are normally only obtained by plugging extra cards into the expansion slots. Those extra features included two onboard serial ports, one parallel port, a floppy disc controller, an integrated hard disc adaptor, and an on-board clock. And the new motherboard was fast - a 12MHz zero wait state machine is no slouch when it comes to running software. Other features of the motherboard included an 80286 microprocessor, provision for up to 4Mb of RAM (random access memory), "Award" BIOS with built-in setup, dynamic input/output control, and 6 expansion slots. Naturally, it is also fully compatible with the IBM PC/AT. THE MAJOR COMPONENTS of the ATcompatible kit (clockwise from top left): 14-inch monochrome monitor, 12MHz motherboard, tower case, 1.2Mb 5.25-inch floppy disc drive, 42Mb hard disc drive and keyboard. In the centre of the picture are the three optional graphics adaptor cards (MDA, EGA & VGA), the hard disc controller card and the optional 3.5-inch 1.44Mb floppy disc drive. AUGUST 1989 7 KE BOARD S CKET S PARALLEL PORT FLOPPY DISC CONTROLLER t IAL P RT THIS IS THE BABY 286AIO motherboard. It's a 12MHZ zero wait state machine with on-board serial and parallel ports, floppy disc controller, 6 expansion slots, "Award" BIOS with built-in setup, and provision for up to 2Mb of RAM. A practical computer But forget about such things as speed and memory and BIOS for the moment. What do those extra onboard functions mean in terms of building up a practical computer? Let's tick off some of the advantages. For starters, you can scratch the need for an input/output (1/0) card - the 1/0 is built directly onto the motherboard. Second, you don't need a floppy disc controller card. And third, if you use an AT-bus integrated hard disc such as a Miniscribe 8051A, you don't need a hard disc controller. As well as leaving expansion slots clear, that can all add up to some big dollar savings. So, we thought, why not approach Electronic Solutions with a view to building up a complete kit computer at a special price? Fur8 SILICON CHIP ther, why not go one better by housing it all in one of those natty new compact tower cases? A tower case takes up far less bench space than a conventional case and, to our mind, is a far more attractive format. The result is the machine presented on these pages. Our aim with the prototype was to bring the price in at under 3000 bucks and so we specified the following: 1Mb (one megabyte) of on-board RAM, a 42Mb hard disc drive, a hard disc drive card, a 1.2Mb floppy disc drive, a monochrome display adaptor (MDA) card, a 14-inch monochrome monitor and MS-DOS 4.01. This gave an all-up cost of $2944, including the monitor and keyboard. Considering the power and performance of the machine, that represents quite good value. Depending on your requirements (and your budget), you might want to specify quite different options for your machine. Want to save $304 at the expense of disc space? - simple, just specify a 20Mb hard disc drive in place of the 42Mb unit. Perhaps you don't need 1Mb of onboard RAM? No problem, just reduce the on-board RAM to 640K and save another $150. Taken together, these two "compromises" reduce the total cost by $454, resulting in a 20Mb hard disc machine with 640K of on-board RAM and a 1.2Mb floppy disc drive for $2490. Alternatively, you might want to build a machine with a few more features. Apart from the features already listed, the options include 1.44Mb 3.5-inch floppy disc drives, expanded memory (up to 4Mb), and EGA (enhanced graphics adaptor) or VGA (video graphics array) cards. By the way, you must use a hard disc drive card with the two hard disc drives that will be supplied. This is because neither of these drives is an AT-BUS integrated type. We'll have more to say about this later on. DOS 4.01 As part of the deal, Electronic Solutions will be supplying Microsoft MS-DOS 4.01 with the kit. This version of DOS offers several new features as compared to older versions. Among these are enhancements to the SELECT command which greatly simplifies MSDOS 4.01 installation and system configuration. In this version, the SELECT command is now a full-screen program that takes you through installation and system configuration step by step. It also creates the corresponding config.sys and autoexec.bat files for you, plus a separate DOS directory. With MS-DOS 4.01 , you don't have to worry about FDISK and all that stuff. Another advantage of MS-DOS 4.01 is that it can support hard discs with capacities larger than 32Mb. Earlier versions of MS-DOS can only recognise up to 32Mb of disc space, which meant that a 42Mb drive had to be partitioned. With MS-DOS 4.01 , you don't have to worry about partitioning the disc. Note that both the 20Mb and 42Mb hard disc drives will be supplied with low level formatting so that setting up will be straightforward. The tower(ing) case We've already briefly mentioned the tower case and our reasons for choosing it. In fact, we reckon this format will become very popular. The "Baby Tower Case" specified measures just 180 x 410 x 330mm and is supplied with the 200W power supply bolted into position. Also supplied with the case is a hardware pack. In addition to a small loudspeaker and the blank backplane brackets, this pack also contains such mundane items as screws, fibre washers, plastic standoffs [for the motherboard), rubber feet and keys (to lock the keyboard). It might look complicated from TABLE 1: WHAT IT COSTS BASIC KIT 1 2MHz Baby 286AIO Motherboard .. .... .... ... .... .... ... .... ...... ... $495 Baby Tower Case ...... .. ... .. ..... ........ ..... .... ..... .. ... ... ........ ...... $1 35 200W Power Supply ......... ..... ... ... .. ........ ...... ......... ... .. .... ... $130 Monochrome Display Card (MDA) ... .... ........ ..... ............ ..... ... $ 99 101 -Key AT Keyboard ... .... .... .. ... ........... .. .. ... .. .. .... ...... ... .... $ 99 1.2Mb Floppy Disc Drive ... .. .......... .... ... ... ... .... ...... .... ... ...... . $195 MS-DOS 4.01 ................. ...... .... ..... .... ....... .. ......... .... ........ $145 TOTAL $1298 OPTIONS 640Kb RAM (18 x 256Kb + 18 x 64Kb) ..... .. .. .... ..... ...... ... ... $395 1 Mb RAM (36 x 256Kb) .. .. ......... ....... .. ..... ...... ........ ........ .... $549 2Mb RAM (18 x 1 Mb) .... .... ......... ... .... .. ..... ... .. .. .. ..... ..... .. .... $750 360Kb 5.25-inch Floppy Disc Drive .. ........ ..... .. ...... .. .... ........ $175 1.44Mb 3 .5-inch Floppy Disc Drive ..... ... ... ... .... ... ... ....... .. .... $199 20Mb Hard Disc Drive (Type 41) ... ... .... ... .. ... .... .... .... .. .... .. .. . $395 42Mb NEC Hard Disc Drive (Type 42) ... ....... ..... ... .. .... .... .... .. $699 Hard Disc Controller Card ...... .... .... ... ...... .... ... .... ... ....... .... ... $1 99 Enhanced Graphics Adaptor (EGA) Card .. ...... ...... ..... .... ..... ... $249 Video Graphics Array (VGA) Card .. .... ......... .... ... ... ..... ..... ..... $4 7 5 14-inch Monitor (Amber or Green) ... .... ...... ..... ... ... ...... ... .. .... $1 99 EGA Monitor ... ...... ..... ... ... ...... .. .... ... ........ .... ... ...... ...... ....... $645 VGA Monitor .... ... .. .. ....... ..... .. .... .... ... .. .... .. ..... .. .. .. ... .. .... .. .. . $685 EGA/VGA Multi-Sync Monitor ..... ......... .. .. .. .. .. .. .. .. .. .... ... ....... $899 Note: these are special kit prices and are less than normal retail prices. The parts are available from Electronic Solutions (see advert pages 4 & 5). the photographs but installing all the parts in the case is quite straightforward. Mostly, it's just a case of bolting each part into position and then hooking up the necessary ea bles and wiring connectors. Well , almost but not quite. There's a definite order to the assembly and there are a number of things to check before installing the disc drives and the motherboard. We'll go through each of these things in turn, just so that there 's no confusion. To simplify things, we'll assume that you're building a machine with similar specifications to ours. If you've specified different options, the order of assembly will be similar so you should have no problems. The disc drives Before mounting the disc drives, it will be necessary to identify and record the leads to the front panel LEDs and switches on the case. On our machine, the yellow and white leads went to the turbo switch; the blue and white leads went to the reset switch; the red and white leads went to the hard disc LED (HDD); and the white, green, black and red leads went to the keyboard lock and power LED. Note that, where LED connections are involved, the cathode lead is always the white one. Don't just accept our colour codes as gospel, though. The colours used on your case may be different so check first. The hard disc drive can now be installed right at the bottom of the disc cage. First, remove the plastic front panel from the drive [just undo the screws), then slide it into the rear of the disc cage with the diecast section upermost. The drive A UGUST 1989 9 1.2Mb FLOPPY DISC · ., , ;r ·- ·,:;_,' -1\, 0 HARD DJ~.C IT MAY LOOK complicated but it's mostly a matter of installing the major parts in the case and then hooking up the control cables and front panel wiring. Take care with the switch and jumper settings (see text). can then be secured using four machine screws (two on either side). The switches on the hard disc drive should be correct if left at the factory settings. For the record, SWl-1 should be set to OFF while SWl-2 to SWl-8 should all be ON. Similarly, SW2-1 should be set to ON while SW2-2 to SW2-4 should be power supply leads can be connected to the on/off switch on the front panel. There are four leads in all and these are simply pushed onto the switch terminals [careful one section of the switch must switch the black leads while the other must switch the white leads). OFF. Before installing the motherboard, you first have to install the RAM chips and check a number of switch and jumper settings. The RAM chips are plugged into six rows of six sockets and these are labelled Ul-U36 on the motherboard. Page 17 of the manual (supplied with the motherboard) shows how to mount the RAM. If you want 1Mb of on-board RAM [ie, 640Kb base memory plus 384Kb extended), then it's simply a matter of plugging 36 256Kb (41256) RAM chips into the 16-pin sockets. The wider 18-pin sockets are for the larger 411000 1Mb RAM chips. The 640Kb memory size requires a mixture of 256K 41256 chips and Now for the floppy disc drive once again, it should just be a matter of leaving everything at the factory settings but it should still be checked to make sure everything is correct. The jumpers for DX, MON, DEN and HDE should all be set to position 1, while USE and DCG should have their jumpers set to position 2. Install the floppy disc drive from the front of the case and adjust it so that the tapped holes line up with the slots in the disc cage. Check that the front panel of the drive is flush with the case, then secure the drive using eight machine screws. With the disc drives secured, the 10 SILICON CHIP The motherboard 64K 4164 chips. In this case, the 41256 devices are plugged into sockets Ul-U18 while the 4164s are plugged into sockets Ul 9-U36. Don't mix the two types on the same row otherwise you will run into problems. Note that the RAM chips can be damaged by static electricity so try to avoid touching their leads when installing them on the board. Also, make sure that all the chips are correctly oriented - the notched ends go towards the expansion slots. OK, we've got the RAM chips installed. It's now a matter of working through the manual supplied with the motherboard and checking off all the switch and jumper settings. Mostly, it's simply a matter of leaving the jumper (or switch) at the factory setting so we'll just mention the changes and the main things to watch out for. First up, you have to set DIP switch SWl according to the amount of RAM installed on the board. The factory setting is for 1Mb of RAM but be sure to set SWl-1, SWl-2 and SWl-3 as required for other RAM sizes. After that, you can flip through the manual until you come to Section 2.13: Display Adapter Selection (SWl-5). The factory setting here is for CGA, EGA or VGA. We opted for an MDA [monochrome adaptor) card and so we moved SWl-5 to the OFF position. You should also check the switch settings for the floppy disc controller and the hard disc adaptor. The on-board floppy disc controller must be enabled (SW2-5 ON) while the hard disc adaptor should be disabled [SW2-6 OFF and Jl 7 set to position 1-2). The motherboard is secured using plastic standoffs [which are first fitted to the board) and a number of metal standoffs which are first screwed into the case. Fit the standoffs, then decide whether you wish to use front or rear entry for the keyboard connector. If you want to use the front entry, which we think is the most convenient, insert the plug connector into the back of the motherboard keyboard socket before pushing the board all the way down. Once the board is locked into white) is later plugged into the hard disc controller card instead. The next most logical step is to connect up the power supply leads. Locate two 4-pin polarised connectors and plug these into the floppy disc and hard disc power connectors. For the motherboard, plug the 6-pin connector with the orange lead into the rear 6 pins of the power connector (Pll). The other 6-pin connector then plugs into the other 6 pins of Pll. Plug-in cards THE SYSTEM SETUP is performed by pressing and holding down the CTRL, ALT & ESC keys simulataneously. After that, you simply step through and correct each item in turn using the arrow keys. This photo shows the setup for our system. Before plugging in the MDA card, check that there are no shorting plugs on JPZ and JP3. If you are using a colour adaptor card (EGA or VGA), then you must set the various DIP switches and jumpers to suit your monitor (these settings will be spelt out in the manual). You will also have to check SWl-5 on the motherboard. Once you are satisfied that all the switch settings are correct, plug the card into one of the expansion slots and secure the backplane bracket to the case. On the disc controller card, check that JPl is closed (single crystal version only) and that JP5 is open. JP3, JP4 and JP6 should all be set to position 2-3. If everything checks out, plug the controller card into another of the expansion slots and plug the connector from the HDD LED into JPZ (the white lead should be adjacent to C24). Cables & battery THIS CLOSE-UP VIEW shows the mounting details for the loudspeaker and for the hard disc drive. The drive is installed with the diecast section uppermost. position (by sliding the heads of the plastic supports into the narrowed channels), the board can be secured to the metal standoffs using the screws provided. Be sure to use a fibre washer under each screw head to prevent shorts on the board. You can now install the speaker (see photo) and proceed with hooking up the various connectors from the front panel LEDs and switches. Pt.3 of the manual lists the pin assignments for all the on-board connectors and this should be followed carefully. Note that there is no provision on the board for the turbo switch connector and so this is simply left unused. Also, don't use the onboard hard disc LED connector (P4) - we've disabled the on-board hard disc adaptor, remember? The connector for the HDD LED (red & The interconnecting cables can now all be installed. Plug the 10-way connector into serial port 1 on the motherboard and the 25-way connector into the parallel port, then secure the DB-25 connectors to the back panel. Note that the red stripe on each cable denotes pin 1. The floppy disc controller cable is installed directly between the motherboard and the edge connector on the back of the drive. Note that the end with the " flipped" sections is installed on the drive while the other end goes to the motherboard. The middle connector is used only if two floppy disc drives are installed. The hard disc drive is hooked up by running a 34-way cable to Jl on AUGUST 1989 11 AFTER SYSTEM SETUP and MS-DOS installation, the computer will boot directly from the hard disc. Note that we were also in the process of installing a 3.5-inch 1.44Mb floppy disc drive when the photos accompanying this article were taken. the controller card and a 20-way cable to J2. There's just one more thing to do before switch on - the battery installation. You must do this otherwise you will lose the initial set-up instructions as soon as you turn off the computer. So install the battery now. It can be secured to the underside of the power supply using the Velcro material supplied. The battery lead then plugs into the P13 connector on the motherboard with the red lead to pin 1. Switch-on Connect up the monitor, keyboard and power cable and switch on. After the BIOS message appears, the machine will go through a series of tests and then display an error message at the bottom of the screen. This is perfectly normal and is solved by running the SETUP program. To do this, press and hold down the CTRL, ALT & ESC keys 12 SILICON CHIP simultaneously so that the screen displays the "Award Software CMOS Setup". It's now simply a matter of entering in the date and time and then using the arrow keys to specify the disc drives fitted and the amount of memory. Note that the 42Mb hard disc drive is a type 42 while the 20Mb drive is a type 41. When all the information is correct, press F10 to record the changes and then press F5. The machine will now go back to the BIOS message and then "hang". We're on the home straight. You now have to install the MSDOS so that the machine will look first at the floppy disc drive and, .if nothing is there, boot from the hard disc. Reach for the DOS pack, take out the "User's Guide .and User's Reference", and turn to page 19. There you will find a step-by-step guide for installing the MS-DOS using the Install and Select programs. To start this procedure, turn the computer off and insert the Install disc into drive A. Now switch on again and wait for the Welcome screen to appear. After that, it's simply a matter of following the onscreen instructions. At the end of this procedure, your computer will boot up directly from the hard disc. By the way, it is a good idea to create a back-up copy of your MSDOS disc (ie, of the working disc created during the installation process). This requires a blank unformatted floppy disc and this will supplied by Electronic Solutions as part of the DOS package. The bottom line The bottom line? - this ATcomputer kit is easy to build, easy to get going and easy to set up. There are lots of options so that you can build it just the way you want and the price is highly competitive. And it's fast - boy, is it fast. You can have one for your very own by contacting Electronic Solutions, PO Box 426, Gladesville, NSW 2111. Phone (02) 906 6666.~