Posted on 08/17/2016 10:29:43 AM PDT by zeugma
I was poking around some old data today from some old backups, and I ran across something the old time computer folks will recognize and thought I'd share.
Many, many moons ago, before the internet was much more than a few government systems set up to 'talk' to each other, we still had PCs and stuff, believe it or not. Granted, compared to the system you can buy for a few hundred dollars today from just about anywhere on the internet, they weren't much, but they were what we had.
There were also things called "magazines" printed on thinly sliced dead trees. These covered just about any topic you could imagine, so of course, there were some dedicated to computers.
In some of these periodicals, you'd sometimes have little programs printed that you could, if you were careful and didn't make any mistakes, enter into an editor on your computer, save, compile and execute. Some were so tiny that if you were using a computer that used the DOS operating system, you could enter into a program called "debug", and almost immediately execute them. Debug was a really powerful and dangerous program, because it would give those who invoked it direct access to just about any scrap of memory or disk on your computer. Used injudiciously, you could easily trash your hard disk, or worse.
Because DOS didn't really have much intelligence to it, it was difficult to write interactive scripts. So, over time I put together a collection of tiny utilities to make my batch files smarter. One such program would read what key you entered, and output the scan code of the key as an error code. So, you could have your batch file prompt for input, then take different actions depending upon what the user entered.
here's the code for "key.com".
N KEY.COM E 0100 B4 00 CD 16 EB 0E 77 06 3C 60 76 02 E 010C 24 DF 3C 00 75 02 88 E0 B4 4C CD 21 RCX 0018 W Q
If you entered the above into a plain text file, and saved it as KEY.SCR, then enter the following from a DOS prompt:
DEBUG < KEY.SCR
you would end up with a program called KEY.COM that would interpret and echo keystrokes to help your batch files a little smarter than they otherwise would be.
The program, KEY.COM is tiny, weighing in at a whopping 24 bytes. However, it's diminutive size did not adversely affect it's utility. An even smaller pair of programs were something I called "WARM.COM" and "COLD.COM". They would reboot your PC immediately. 'Warm.com' was the equivalent of pressing the [ctrl]-[alt]-[delete] key, which would reboot without performing a full POST (Power On Self-Test). 'Cold.com', on the other hand, was like powering your computer off and back on.
If you were to run the following through DEBUG as shown above, you'd create both programs.
N WARM.COM E 0100 B8 40 00 8E C0 26 C7 06 E 0108 72 00 34 12 EA 00 00 FF E 0110 FF RCX 0011 W N COLD.COM E 0100 B8 40 00 8E C0 26 C7 06 E 0108 72 00 00 00 EA 00 00 FF E 0110 FF RCX 0011 W Q
It is easy to spot the difference between the two programs. The bottom line, was that the program told your computer to jump to a certain memory location. The different locations controlled the different boot types.
One final debug script I'd like to mention is 'BEEP.COM'. It wasn't the most powerful program in the world, as it had one simple job to do. It would make your computer speaker beep once. That's it. What is cool about it (to me any way) was that the entire executable was a whopping 6 bytes! To this day, I've never seen a smaller functional program. Here it is, in all it's awesome and tiny glory:
N BEEP.COM E 0100 B8 07 0E CD 10 C3 RCX 0006 W Q
The dates associated with the files indicates how long ago I was talking about...
-rw-r--r-- 1 zeugma zeugma 6 Jan 28 1994 BEEP.COM -rw-r--r-- 1 zeugma zeugma 56 Mar 11 1995 BEEP.SCR -rw-r--r-- 1 zeugma zeugma 17 Dec 22 1991 COLD.COM -rw-r--r-- 1 zeugma zeugma 94 Feb 13 1996 COLD.SCR -rw-r--r-- 1 zeugma zeugma 24 Dec 6 1992 KEY.COM -rw-r--r-- 1 zeugma zeugma 17 Dec 22 1991 WARM.COM -rw-r--r-- 1 zeugma zeugma 94 Feb 13 1996 WARM.SCR
Are you talking about punch cards like on an IBM 360 using the Hollerith code, or are you talking even older school like back in my telecom career with punch tapes and the Baudot code used in transmitter distributors for teletype operations?
Old-time ping! :)
I’ll read this just before bedtime to help me sleep.
J/k
I started with a Commodore 64.
That directory listing at the end looks like *nix, not DOS. “ls -FAC”, I believe.
I wrote a few low level hardware programs using debug, mostly for I/O interfaces. Remember Borland Turbo Assembler?
Those were the days!
We used to ‘joke’ about a ‘gigabyte of EXPANDED MEMORY and a One Gigabyte Hard Drive as being the ultimate machine!
Windows was a ‘novel’ concept, Version 3.1.
DOS was where the REAL computer guys worked!
I even had some experience with a precursor to MS-DOS, called CP/M......................
Been there did that. A good era, much enjoyed, with good riddance.
Spent much time perusing the BIOS source code for graphics calls. If I wanted a game, I wrote it.
beep.com was awesome !!
No, he’s talking about MAGAZINES, like Computer Shopper and PC Magazine!..................
“In some of these periodicals, you’d sometimes have little programs printed that you could, if you were careful and didn’t make any mistakes, enter into an editor on your computer, save, compile and execute”
LOL! Yes!
Astronomy Magazine used to print out programs in BASIC like that every month. I did one in QBASIC that was an orbital simulator that took forever to do, and the debugging was just as long because there was always some command that didnt work with what you were programming with, but to run that and watch it go after you fixed it? That was art right there.
My ‘first’ was a Timex-Sinclair TS-1000!...................with 16k memory extension module!...............
Dont forget Compute!, MacUser, PC Computing, and Byte.
So many great titles back then.
I found a bug in BEEP.COM.
Beeps were actually a series of clicks that you could program to make wierd sounds.
Some of us worked in VAX/VMS, MVS, and JCL ... but that was on big(ger) iron.
I used to read Computer Shopper cover to cover!
It was as thick as a phonebook!................
I used turbo c for quite a while.
I guess I shoulda took a clue when the dweeb mentioned “DOS”......warn’t no “DOS” when I started.
Sheet, I thought we wuz talking old timer crap here. I remember sending and receiving emails over a Model 204 to someone in Arizona in 1989.... DOS my patootie....
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