How to waste computer memory?
Gene Heskett
gheskett at wdtv.com
Fri Mar 18 10:11:21 EDT 2016
On Friday 18 March 2016 06:44:05 cl at isbd.net wrote:
> Gene Heskett <gheskett at wdtv.com> wrote:
> > On Thursday 17 March 2016 17:37:02 alister wrote:
> > > On Fri, 18 Mar 2016 07:42:30 +1100, Chris Angelico wrote:
> > > > On Fri, Mar 18, 2016 at 7:31 AM, <cl at isbd.net> wrote:
> > > >> Rick Johnson <rantingrickjohnson at gmail.com> wrote:
> > > >>> In the event that i change my mind about Unicode, and/or for
> > > >>> the sake of others, who may want to know, please provide a
> > > >>> list of languages that *YOU* think handle Unicode better than
> > > >>> Python, starting with the best first. Thanks.
> > > >>
> > > >> How about a list of languages that Unicode handles better than
> > > >> ASCII? Like almost every language *except* English.
> > > >
> > > > Like every language *including* English. You can pretend that
> > > > ASCII is enough, but you do lose some information.
> > > >
> > > > ChrisA
> > >
> > > as we all seam to have bitten the troll's thread
> > > "how to waste computer memory"
> > > give it to an delusion-ed incompetent to play with
> > >
> > > it is now 2016 not 1978, Memory is cheap. plentifully and fast
> > > there is more than enough to go arround
> >
> > While you all are trying to play can you top this, I just have to
> > comment that in 1978 I paid $400 for a kit to put 4k of static ram
> > in a Cosmac Super Elf. And the code I wrote for it, looking up in
> > the RCA programmers manual to get the hex value I then entered via
> > the onboard monitor facility with its 6 digit led display, was still
> > running in 1995 at that tv station.
> >
> > So the obvious question then is, will any of your python code still
> > be running and doing its labor saving and dead on the video frame
> > timing job several times daily, 17 years hence?
>
> I wrote a Cosmac assembler for the Cosmac. :-)
>
Chuckle. I thought about that, but by the time I was knowlegable enough
to attempt that, I also realized that it would take more memory than the
kit had. And since by then it was beginning to do the job, I wasn't
about to ditch what I already had. I just pulled a paper copy of that
code odd the shelf where its been stashed for 26 years, used $8FF bytes
of that $1000 that cost us $400 at the time. The I/O was done, and the
tape machines were doing as they were told, but I had used a packaged
chip for the video it needed, but that turn out to be so small on a 5"
B&W monitor screen as to be worthless. So I designed and coded up a
video that gave them an academy countdown timer 103 line tall on a 262.5
line NTSC screen, which was all the video it needed. That displayed
timer was, taken over a calculated year, had considerable less drift
from wall clock time than any skip frame time code std then extant, and
I wrote that too, but it was slaved to house synch since the machines
were too. What it did was let the operator run the machine in slow
search mode to find the first frame of a commercial to be switched to
air, then the operator punched one of 6 buttons to tell the cosmac how
long the commercial was, another button to tell it to put a new academy
leader using its video on it, and a go button. It then backed the
machine up 12 seconds from the position it was parked at for 1st frame,
the rolled it fwd at norml speed, commanded the video to go into insert
mode at 1st frame -10.0 seconds so it recorded the countdown from 9.9 to
2.0 seconds, triggering an audio tone to be inserted on channel 2 of the
tape decks audio which was used by an automatic station break machine.
At 2.0 s econds the insert was turned off so the last frame seen was 1
field of 1.9. Then it tracked the time and inserted the audio tone
again at 24.9 seconds if it was a "30" second commercial. This 2nd tone
told the automatic station break machine to roll the next commercial in
the next machine if the current one wasn't the last in this break.
Otherwise its video fell thru to the film chain which had an ID slide,
so folks saw an ID at the end of the break for the accumulated tenths of
a second gained by trimming each spot .1 seconds.
That video turned out to be pretty easy, I broke the line into 32 time
slots, counted out the first 16, then enabled a counter that from a
74LS150 sampled the output of a 74LS245 8 bit latch which was diode
steered to the inputs of the 74150, so I had a left edge of the
character about 3 u-secs wide, a bar from there to the center of the
character, a 3 u-sec dot there, another bar to the right edge, and
another 3 u-sec dot there. That occupied 6 spots using the MSB nibble
on the data in the latch, then some blank time and it started the LSB
nibble of the data. This was from line 100 to line 103, where a dma
cycle was generated and the cosmac replaced the data with another byte
for the next 47 lines, at line 50 another DMA byte was written to the
latch for the center horizontal bar, at line 53 that was replaced by
another byte for the next 47 line, and finally the last of 6 bytes DMA'd
to the latch made the bottom bar of the character, and at line 103, the
latch was cleared so the remainder of the frame the output was black.
At line 200, the bottom of the character, a 3 count wide center decimal
point was generated. Some simple logic made that into useable video and
it accomplished the task for the tech directors of being able to read it
from across the control room when they were queing things up for a hand
run break.
In those days, dubbing a 3/4" u-matic tape was a serious quality loss and
by doing this to the tape the production dept handed us, improved the on
air image considerably by getting rid of a copy generation loss cycle.
It also tightened up the break timing to an accuracy consistency they
had never experienced before at that smaller market station.
All this BTW, was while the Chief Engineer had a heart attack and took a
good share of a year off to "recover", 2 weeks after I had walked in the
door as the Assistent Chief engineer. I had just about figured out where
all the light switches were. So I suddenly was doing his job too.
Fortunately I only got into trouble for helping the FCC get to the
transmitter to inspect it when he came calling as it turned out to be
their responsibility to get there, which they would have had to spend a
kilobuck or so for helicopter time. The tx was on Shasta Bally
Mountain, and road access was so poor that we changed operators every 2
weeks via helicopter. So this stations need for remote controls because
there was a limit to the hours in a day that the operator could be "on
duty" caused the FCC to use us as a model when they wrote the remote
controlling specs. To get there by road, you needed a snow cat or
similar tracked vehicle, because the road at one point was thru a fine
powdered rock about 10 feet deep and normal tires would sink in just
like quicksand, for about 100 feet. We'ed taken some rock and oil up to
stiffen it up, and the forest service made us take it back out, cost us
over 200k to satisfy the p&%cks. I'd made the mistake of offering to
take the field inspector up with our snow cat, mainly because I had
never been there either.
> However I doubt it's still being used, a year or two after I wrote it
> we migrated to a Tektronix development system that ran Unix (wow!).
The only unix machine we were had at my last station was a AT&T 3b2,
which ran so hot in its 24/7 job that I posted a fire extinguisher next
to it. Never had to us the extinguisher though. That thing would cook
the goodie out of all its electrolytics in about a year. But we had a
contract, so it wasn't up to me when it puked. But I also had a copy of
that unix stashed in my office, which was kewl, except it was locked
down tight & the passwd wasn't available to me. Once the tech needed to
restore from those disks, so I trucked them out, only to discover they
weren't readable, seems the night janitor had been playing with my
office computer which was a trs80 color computer3, and had reformatted
some of those disks in the coco3's drives, oops, we had a new janitor
the next day. But the tech had his own copy so was able to rescue it.
They had been reformatted to disk basic format, but I ran os9 on it. If
I saw a dumpster full of 3b2's today I wouldn't even put fingerprint on
the cleanest looking one.
I didn't intend to write a weekly paper here, but it sure looks like it.
Blame it on the old fart who likes to ramble on?
Cheers everybody, Gene Heskett
--
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>
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