rogerh@megaron.UUCP (03/08/86)
The Tektronix 4051 (one of the first desk-top computers) had a microprocessor (6800 I think) deep inside it. Although the machine's native language was Basic, there were (undocumented) hooks to download and run machine code. The machine also had a synthesized bell. The result, of course, was that 4051 was one of the favorite musical instruments in some parts of Tek. Anybody remember how to walk an IBM 1130's disk drives? I recall stories that the right program would start them marching across the room. Roger Hayes
gerber@mit-amt.MIT.EDU (Andrew S. Gerber) (03/09/86)
In article <922@megaron.UUCP> rogerh@arizona.UUCP (Roger Hayes) writes: >Anybody remember how to walk an IBM 1130's disk drives? I recall >stories that the right program would start them marching across the >room. A friend of mine once told me how he used to do just that at U of Delaware. He used to do it from a terminal room where you couldn't see the machine itself, but you'd know when it happned - the disk would pull either it's power plug or it's connection to the mainframe off, and the machine would crash. The TRS-80 Model 1 used to put out so much RF interference, that one way of adding sound to ANY program was to put a small AM radio right by the machine, and listening to the electronic "music". Some programs even used this trait of the trash-80, instead of connecting up the external speaker. -- +-----------------------------------------------------------------------------+ | Andrew S. Gerber MIT '87 Visible Language Workshop | | gerber@mit-amt.MIT.EDU, gerber@mit-mc.lcs.mit.edu, gerber@athena.mit.edu | | UUCP: decvax!mit-eddie!mit-amt!gerber decvax!mit-eddie!mit-athena!gerber | +-----------------------------------------------------------------------------+
jeffj@sfmin.UUCP (J.S.Jonas) (03/11/86)
> Anybody remember how to walk an IBM 1130's disk drives? I recall > stories that the right program would start them marching across the > room. > Roger Hayes I have very fond memories of the IBM system 1130, and the disks (2314 disks? 2310 disks? I forgot the number) were VERY SLOW! The head had a ratchet mechanism (I have one in my closet as a souvenour) to step the head a track at a time. 100 tracks per inch, 203 tracks edge to edge. It took about 1 second to seek from edge to edge, so IBM's original disks NEVER could do that. The Calcomp DS-12 disk drive was another matter. It was attached to the 1130, and used an 11 platter disk. The heads were operated on a linear motor, and moved FAST! I could imagine it rocking if you went from edge to edge repeatedly! There were other non-IBM disks that could be used, and maybe those marched well too. But not the original disks Jeff 'archiver of 1130 parts' Skot {ihnp4 | allegra | cbosgd } attunix ! jeffj
henry@utzoo.UUCP (Henry Spencer) (03/12/86)
> The Calcomp DS-12 disk drive was another matter. It was attached to the > 1130, and used an 11 platter disk. The heads were operated on a linear > motor, and moved FAST! I could imagine it rocking if you went from > edge to edge repeatedly! ... At the engineering lab where I worked part-time and summers while I was an undergrad, we once got in the latest thing in disks -- an RK05. Well, it was the latest thing in disks for this lab, which was pretty backward in some ways. So we ran diagnostics on it. The RK05 was fairly high up in an otherwise largely-empty rack. One of the diagnostics tested all the possible sizes of seek, from smallest to largest. Since larger seeks take longer, the frequency of the motion slowly swept downward. When it hit the resonant frequency of the rack, the rocking motion was impressive. -- Henry Spencer @ U of Toronto Zoology {allegra,ihnp4,linus,decvax}!utzoo!henry
sutter@osu-eddie.UUCP (Bob Sutterfield) (03/17/86)
In article <104@mit-amt.MIT.EDU>, gerber@mit-amt.MIT.EDU (Andrew S. Gerber) writes: > ... > The TRS-80 Model 1 used to put out so much RF interference, that one > way of adding sound to ANY program was to put a small AM radio right > by the machine, and listening to the electronic "music". Some > programs even used this trait of the trash-80, instead of connecting > up the external speaker. One of my earliest and fondest memories of those new-fangled PC's was when a friend built the first Altair on the block. It was endowed with something like 128 bytes of memory, an 8080 CPU, that venerable Altair bus, and a front panel with switches and lights. The blinking lights impressed the girls, but... that's another story. One issue of Dr Dobb's (I believe) told of how to use timing loops to play music through an AM radio set near the machine, just as described above. We spent several happy hours getting it to play the Star Trek theme Just Right, loading values for duration and pitch into the display registers from the toggle switches, and depositing into those precious few bytes of user memory... ah, for the good old days! -- ----- Human: Bob Sutterfield Mail: sutter@osu-eddie.UUCP sutterfield-r%osu-20@osu-eddie.UUCP or: sutter@ohio-state.ARPA sutterfield-r%osu-20@ohio-state.ARPA
mc68020@gilbbs.UUCP (Tom Keller) (03/21/86)
In 1978, a company in my area which specialized in fruit orchard temperature
alarm systems (it being necessary to awaken the farmers to start the smudge
pots and ventilators (giant fans) in order to prevent damage to the fruit)
decided they wanted to go into the TRS-80 I peripherals business. They hired
me as an engineering technician and programmer.
There I was, working on programs to drive the peripherals, and having
even the simplest programs crashing and going haywire for no apparent reason.
Being brought up to never assume it's the machine's fault, I spent several
weeks trying to figure out what I was doing wrong.
The one day my boss asked me to go to the company next door and assist them
with a problem (they built hydraulic lift units, like the ones you see being
used in construction...turned out we built the electronic control boxes for
their lifts). I walk into the shop, and am confronted by 12 extra heavy duty
arcwelding machines (these guys were welding steel up to 2" thick!). After
solving their problem, I traced the power mains. Sure enough, we were drawing
our AC feed from the same source they were, no transformers between us.
A few hours, a couple of isolation transformers and caps later, and all
of a sudden my code runs perfectly.
The boss still didn't believe it, when I showed him the finally working
code...he had pretty much decided I was a flop as a programmer. They decided
two weeks later not to go into computers...too volatile, they said.
--
====================================
Disclaimer: I hereby disclaim any and all responsibility for disclaimers.
tom keller
{ihnp4, dual}!ptsfa!gilbbs!mc68020
(* we may not be big, but we're small! *)