The 486 Half-Top


Awhile ago when I was looking for a pre-pentium project and before I came across what became The Little Bird ,  I ran across the only 486 I could get my hands on.  A Sharp PC3010 laptop that had lived a rough life.  Actually, I am not sure how rough because it was suffering from a common problem for these machines.  I’ll show you that below.

This is going to be a longer article.  I normally break these up into several article segments but this time I am just going to blast your brain balls all at a once with the initial setup article.  Check out the original selling price int he ad below.



I found a battered Sharp PC3010 laptop minus the AC adapter.   Let’s take a look at what this once was when it was in it’s prime! 

There was a time when these were selling new for $1899.


The ad lists this model as a DX2/66 4/320.  Back in this day that was code for a 486 dx2-66 MHz processor, 4 megabytes of ram, and a 320 megabyte hard drive.  That was considered OK for specs on this level machine.  As you can see there are higher spec models than this.  Check out those Compaq prices!!!!  Whew!!  These prices are expensive even now.  Can you imagine how out of reach they were around 1995?

I didn’t pick mine up for anywhere near that much but it did have those specs in the ad.  I opted to upgrade the memory.  That was a task that involved tracking down a vendor who actually had some in stock for about $34.00 for 16 Megabytes.  Patience is be rewarded!  The initial 4 megabytes is non-removeable and I am pretty sure this is now maxed at 20 megabytes of ram.

While waiting for the memory to arrive I began the testing.  I plugged the laptop in with an ac adapter I had on hand because of course the battery no longer holds charge.  The machine got power indicator lights but the screen was not working, which is as advertised to me.  I connected a Dell 15″ Flat Panel monitor to the VGA port.   I knew the Dell would easily handle the resolution and voila;  I had picture but no boot to an OS.

The CMOS clock battery was also bad so the BIOS did not have the hard drive settings saved anymore.

Time to pop the drive out and see what we have. So this is what we have:



The 1995 Hitachi DK221A-34…. Yes …. we know these well.  

Let’s setup that BIOS to see this drive.  

During this test the memory upgrade arrived and I installed that right away!  Check out that total memory with the upgrade in one of the images below!! NICE!!!!




Back in its day this BIOS didn’t auto detect the hard drive.  One had to input parameters in the BIOS so it knew what the heck size it was,  or at least an approximation.  BIOS at this time had several pre-configured options to choose from and some of them would even boot a drive. 


There it is. Default date and no hard drive parameters.


My figures are:  CYL: 692   HD: 16   PRE: 0    LZ: 0    Sec Size: 60

This gave me the 324 megabyte size I needed.  I will need to enter this whenever I use this machine until I decide it is worth it to replace the CMOS battery.  If this was to be used regularly I may do that then.

I mentioned this may have had a rough life but in fact may also have suffered from a common problem with these laptops. 

Below are some images of another one of these from some random web pics of how this should look in first picture.  Second is the typical problem


If only that was the way I received mine.  But alas, I was desperate for a 486 so I got this one:



My plastic was not just cracked and popped apart, the hinge was broken.  Bummer!  Every time I opened or closed it more plastic broke off.  It was cheap because… well the screen didn’t work and all this was broken.

I pondered briefly and chose the course of action. This laptop was becoming….

The 486 Halftop!


I wanted a 486 and didn’t care if it is a laptop or not.  So I did the thing!  In the car world we would say we chopped the top!


The original screen didn’t work long and I was going to have to use an external monitor anyway so this it that thing! 

Let’s take a peek around the machine! 



The hard drive caddy is out and there is the 1.44 floppy drive.  This is how I am going to load DOS this time for nostalgia. 

To save time I generally hook the hard drive up to another machine to format and sys the drive then copy everything to an install folder and go from there.  Not this time!  I want to relive the experience!!!









From the back you can see behind the flip-down door, we have a 9 pin serial port, the 25 pin parallel port,  and the nifty SVGA 15 pin port as well as the IRDA sensor above the flip-down door.


Then the cooling fan.  To the far right is a PS Port.  I will note the keyboard and trackpad do work on this Halftop.  With the Mouse driver installed the trackpad will even work in DOS!



Now that we are familiar with the 486 Hallftop, Let’s give it some juice again!



After a couple minutes monkeying with the BIOS setting again we have access.  DOS has been loaded so we can run the MSD tool.


That’s where we are until next time when we crank up some applications on this.  If you hadn’t checked out the article on the other 486 – The Little Bird – peep that by clickering this link