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View Full Version : Have things relly got smaller



vic user
November 25th, 2003, 03:25 PM
I finallly got around to poking around with an XT clone I salvaged, from the garbage about a year ago.

Glad I did, because it has lots of neat programs on the hard drive, like Windows 1.0, Lotus, WP51, etc..

I also got to install PASCAL 6.0 via 5 1/4 disks!

I wish I could figure out what version of DOSA it has, and it seems not to have a ROM BIOS. I tried hitting F1 or DEL and just beeps is all I get.

But the thing that amazes me, is how large everything is, compared to my most powerful PC, a pentium 166 :)

The graphics card on the XT is almost as long as the case, the hard drive is pretty big, and the RAM chips seem to go on forever, and I only have 640k! The motherboard is pretty big as well.

Then I look at my pentium 166 with 48 megs RAM, and it looks so tiny.

I can just imagine what the size difference will be with the XT and a computer 10 years from now!

Chris

mbbrutman
November 26th, 2003, 06:25 AM
You need to get off those Commodore products. :)

An XT has a BIOS. All PCs do. There just isn't a setup screen in the BIOS, which is what I think you are referring to.

To setup a PC or XT you used dip switches on the motherboard. The dip switches set the video card type, the number of installed floppies, and the amount of memory. There was only one type of floppy, so you didn't have to set that. They didn't have built-in clocks and calendars, so you didn't have that either. If the machine had a hard drive, the controller was carefully matched to the drive, so no configuration was needed.

It wasn't until the PC AT that IBM type machines had a CMOS configuration. And even on that machine you couldn't hit F1 or DEL to get to it - you ran it from diskette. One of the later clones finally built the setup screen into the onboard BIOS of the machine.

In general, the BIOS of any PC is responsible for starting it up when you apply the power and providing some basic services. Startup on a modern machine is much more complicated than on the old timers - there is more to initialize and probe. The setup screen is just a small part of the BIOS.

vic user
November 26th, 2003, 06:42 AM
Thanks about the BIOS thing.

When I first turn on the XT, it takes I would say about 20 seconds until I see something appear on the screen.

Then it goes into something called "InterGlobe Communications" or something like that (I am at work and do not have the XT in front of me), which then says that the printer port and the communications port have been detected.

Then the screen clears and then "Computer Turbo 2.0 1985" appears and this is followed by "International Computer (or is it Business?) System"

then my config.sys and autoexec.bat fire up.

The InterGlobe thing only come on when I actually power down and then power up the XT. It does not appear when I just do a soft reboot.

As for Commodore things, I am afraid no amount of therapy can save me :)

Chris

mbbrutman
November 26th, 2003, 09:50 AM
It's a clone - who knows what it does. But if it's an XT clone, it probably won't have a setup screen as that was done using DIP switches.

My IBM PC is so old you don't even see it counting the memory - it's just a blinking cursor until it's ready to boot DOS.

I always thought the Commodore stuff was pretty cool .. if only it were a little better built, then the company's reputation wouldn't have gone down the toilet ...



Mike

Classicsat
January 27th, 2004, 01:42 PM
Some XT clones had an RTC chip, either on the motherboard (Which the BIOS would set the clock from RTC, and viceversa), or on an add-on card (usually as part of an all-in-one I/O card), requiring an application diskette,

About HDDs: The controller card would be programmed for the drive size with a jumer or dip switch, and the card would have it's own BIOS (which would have the routines to boot form the drive, and low-level format)

Terry Yager
February 2nd, 2004, 03:10 PM
An XT has a BIOS. All PCs do.

<snippage>

In general, the BIOS of any PC is responsible for starting it up when you apply the power and providing some basic services. Startup on a modern machine is much more complicated than on the old timers - there is more to initialize and probe. The setup screen is just a small part of the BIOS.

OTOH, CP/M machines don't have a ROM-based BIOS. They read thier BIOS from the bootdisk.

I dunno how much simpler the BIOS on a CP/M machine is, but I'm going to have to find out *real soon now*. I'm going to have to take a crash course in BIOS modding if I replace my hard drive with a bigger one. (Unless I can dig up a pre-built Kaypro 10 BIOS that recognizes an ST-225 hard drive. I know they're out there somewhere???)

--T