chip swelling up and getting fried

[Pippa]

On Sat, 07 Aug 2004 23:37:55 -0700, Sanjay Punjab wrote:

I go through alot of that "canned air" stuff.
Its great for cleaning electronics, computer keyboards etc. etc.
I have been wondering if alternate products like this are more
economical.
http://www.circuits2u.net/pages/CO-2-DBL.htm
http://www.allbrandelectronics.com/prod.itml/icOid/7899
These co2 cartrdiges are as cheap as 50 cents each, but its difficult
to know how long they last compared to a 10 ounce can of canned air.
Just looking for some ideas.

Buy yourself an air compressor!

If you need to have a portable source of compressed air, fit a schroeder
valve to an old canned air can, so you can re-pressureise it using the air
compressor. The schroeder valve fittings are usually made of brass, so are
very easy to solder into a hole punched in the can.

You would have to be careful not to put too much pressure into the can
because of the risk of explosion, but it wouldn't matter that you cannot
store very much air in each can, just re-fill them when you get back to
the workshop.

A schroeder valve is a car tyre valve.

Pip

 

[Jim Thompson]

On Sun, 08 Aug 2004 15:31:15 GMT, Rich Webb
<bbew.ar@mapson.nozirev.ten> wrote:

[snip]

There are also off-the-shelf canned air bottles that come with a
re-pressurizing schrader (schraeder?) valve in the base. Google
for "RR6000" for an example. That's the "ReAir Refillable Duster"
from Read/Right.

"Schroeder valve"

What do you do about the gradual accumulation of water in the
canister?

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[Rich Webb]

On Sun, 08 Aug 2004 09:06:39 -0700, Jim Thompson
<thegreatone@example.com> wrote:

On Sun, 08 Aug 2004 15:31:15 GMT, Rich Webb
bbew.ar@mapson.nozirev.ten> wrote:

[snip]

There are also off-the-shelf canned air bottles that come with a
re-pressurizing schrader (schraeder?) valve in the base. Google
for "RR6000" for an example. That's the "ReAir Refillable Duster"
from Read/Right.

"Schroeder valve"

I'll take your word for it but I only get 65 hits on google for
"schroeder valve" (w/quotes), 1690 for "schraeder valve", and 6300 for
"schrader valve." Also just 5 for "schröder valve" and 90 for "schräder
valve." If I was a betting man I'd go with schräder as the original.

Maybe that's another reason to prefer presta valves on the bike. I'm a
rotten speller in the best of circumstances... ;-)

What do you do about the gradual accumulation of water in the
canister?

They recommend tossing it after about 100 refills for just that reason.
Of course that could be modified if you're filling it from a source with
a moisture separator but you'd probably not get their liability
insurance carrier to agree to that.

It *looks* like the valve body can be unscrewed from the base of the can
so it might be possible to dry the inside that way. And, of course, if
it's a standard schr[oe|ae|a|ö|ä]der valve the stem is removable.

--
Rich Webb Norfolk, VA

 

[Ryan Wheeler]

Makhan wrote:

Hello all,

I have a very typical problem with a twist. Here goes:

I have a main loop running a piece of code. However, upon receiving
character '0' from serial port (or any 8bit code for that matter), I
want to read 8 or 16 or lets say n number of bytes from serial port.

So here is what I did, I created an updateFlag bit which gets set
whenver the true code is reached and the ISR quits. Whenever in the
main loop I reach the place for checking updateFlag, I deactivate the
ISR for Serial Port and assuming that now the serial port will act
just as normal, I run a debug code of reading a byte and outing it.
Only the serial port interrupt flag remains inactive while I am in
that function.

So the ISR goes like:

ISR_SP:
JBC TI, QUITY ; if TI caused it, just quit
MOV A, SBUF ; if '0' = 30 then update the IDATA
ADD A, #-30H ; else skip the update
JNZ QUITY
SETB UpdateFlag
QUITY:
RETI ; if TX irq just returns

and the main loop:

while (1)
{
if (UpdateFlag == 1)
{
/*---------------------------- Debug ------------------------*/
EA = 0;
choice = GetByte();

choice++;

OutByte(choice);

UpdateFlag = 0;

EA = 1;
}

// Some functions here

My problem is this that the ISR works fine if I dont involve serial
port reading writing, that ISR would turn on or off any port correctly
upon receiving character '0'.

Similarly the GetByte and OutByte routines work fine as well when
Serial port is not on interrupt.

Its only after combining both I end up in problems, can anyone see any
potential problem in the approach?

Thanks in advance

Makhan

thou shallt never disable the interrupt on a recv serial port.

 

[Dan Henry]

makhan_rocks@hotmail.com (Makhan) wrote:

So the ISR goes like:

ISR_SP:
JBC TI, QUITY ; if TI caused it, just quit
MOV A, SBUF ; if '0' = 30 then update the IDATA
ADD A, #-30H ; else skip the update
JNZ QUITY
SETB UpdateFlag
QUITY:
RETI ; if TX irq just returns

One problem that has not been mentioned by others (at least in
c.a.e.), is that your ISR does not save and restore ACC and PSW.

Oops!

--
Dan Henry

 

[Jamie]

don't disable the IRQ function.
when receiving a character have the IRQ
service simply put it in a recircular buffer.
using 2 pointer regs to keep track of the next
one to reed from the buffer and the next one
to write to the buffer.
when the two pointers match this means there
is no characters in the buffer.
when ever they don't match you read the character
from the buffer of the current next-to-pointer then
increment that pointer, when storing new characters
you simply store it using the next-to-write pointer and
then increment that pointer for the next..
now, before storing the new incremental results of the
Next-To-write pointer you should first make sure that it
does not equal the current Next-To-Read pointer! other
wise this indicates an over flow and some form of error
should be set ..
your buff could be a simple 16 bytes or more depending on
how much traffic your processor will take.
lets assume its a 16 byte buffer, you do this in
math
Next-to-read = (Next-to-read+1) and H0F; ( $0F, 0x0f etc. take your pic);
that will create a nice wrap around buffer..
etc..


Makhan wrote:

Hello all,

I have a very typical problem with a twist. Here goes:

I have a main loop running a piece of code. However, upon receiving
character '0' from serial port (or any 8bit code for that matter), I
want to read 8 or 16 or lets say n number of bytes from serial port.

So here is what I did, I created an updateFlag bit which gets set
whenver the true code is reached and the ISR quits. Whenever in the
main loop I reach the place for checking updateFlag, I deactivate the
ISR for Serial Port and assuming that now the serial port will act
just as normal, I run a debug code of reading a byte and outing it.
Only the serial port interrupt flag remains inactive while I am in
that function.

So the ISR goes like:

ISR_SP:
JBC TI, QUITY ; if TI caused it, just quit
MOV A, SBUF ; if '0' = 30 then update the IDATA
ADD A, #-30H ; else skip the update
JNZ QUITY
SETB UpdateFlag
QUITY:
RETI ; if TX irq just returns

and the main loop:

while (1)
{
if (UpdateFlag == 1)
{
/*---------------------------- Debug ------------------------*/
EA = 0;
choice = GetByte();

choice++;

OutByte(choice);

UpdateFlag = 0;

EA = 1;
}

// Some functions here

My problem is this that the ISR works fine if I dont involve serial
port reading writing, that ISR would turn on or off any port correctly
upon receiving character '0'.

Similarly the GetByte and OutByte routines work fine as well when
Serial port is not on interrupt.

Its only after combining both I end up in problems, can anyone see any
potential problem in the approach?

Thanks in advance

Makhan

 

[Al]

In article <9geRc.75$cq.59@fe39.usenetserver.com>,
Bill Velek <billvelek--NO-SPAM--@alltel.net> wrote:

I'll get right to the point, and then add more info below for those who
want to read further. I don't know if this sort of a device exists, and
I've just spent all afternoon googling -- trying to find one -- without
any success at all. I hope that some kind person here will be able to
point me in the right direction. Thanks in advance for any help.

I'm looking for a programmable digit thermostat with a short probe that
just needs to reach about 2 inches through an insulated wall; in other
words, I want to mount the thermostat on the outside of a cabinet to
monitor and control the temp on the inside of the cabinet. I built the
cabinet a few years ago to ferment ale, but now I'd like to expand its
ability to include lagers which require more careful, critical control.

For ales, I used just a cheap household hvac thermostat mounted on the
inside, and there was no need for it to be programmable or even visible;
I just set it and forgot about it until the ale was done fermenting
about a week later. In fact, cooling was generally only important for
about the first 4 or 5 days, and the temperature requirements for ales
are so rough that most people don't use any cooling system at all except
perhaps to drape a wet towel over the fermenter to cool by evaporation.
I would just set my temp on 70F, and my system worked _very_ well.
The thermostat cycled a small fan (the type used to cool CPUs), and the
fan moved cold air from the lower ice compartment into the chamber where
my conical fermenter is suspended.

But lagers require _sustained_ cooling and conditioning, lasting perhaps
two months, with significantly cooler temps in the 35F to 55F range, and
with gradual, slow temperature changes (in contrast to ales which can
have a constant temp). If it isn't possible to program a thermostat to
constantly drop the temp at a controlled rate (e.g., 4-5F/day, max),
then I could manually lower the temp one degree every 6 hours or so, but
that would make having the control on the outside even more important.

What most homebrewers do is buy an old chest freezer and then change the
thermostat, but they usually use glass carboys as fermenters. I have a
conical fermenter which is too tall to put inside a chest freezer, and
my cabinet also doubles as the frame to support it. Besides, I'd really
like to try making a lager or two before deciding if I want to invest in
an extra freezer and converting it.

Also, if it turns out that my ice-cooling system isn't up to the job*, I
intend to try to augment the cooling by putting the system out in our
breezeway during the winter, but that presents the possibility of things
getting too cold, so I'd also like to be able to use the thermostat to
control some small heating device -- either a lightbulb or perhaps some
heat-tape like those used to prevent pipes from freezing. I figure that
the wires that usually control the air-conditioning will control my fan,
and those that control the heater will control my light-bulb or heating
strip.

*As for cooling power, the outside of my cooler is 16.5" x 16.5" x 34.5"
and it has 1.37" thick styrofoam (double 11/16") on all sides and top,
and 11/16" thick styrofoam between the two compartments. The lower
compartment can hold four frozen 1-gallon milk jugs, although I want to
play with that a bit because I'd like to suspend a 1/2-pint mason jar at
the bottom of my fermenter to collect yeast, etc.

Any comments or suggestions will be appreciated. I hope someone will be
able to help. Thanks.

Bill Velek -- remove the "--NO-SPAM--" from my email address

Check out this web site. I've used their stuff for controlling chemical
baths.

http://www.omega.com/

Al

 

[Phil Hobbs]

CBFalconer wrote:

Jamie wrote:

don't disable the IRQ function.
when receiving a character have the IRQ
service simply put it in a recircular buffer.
using 2 pointer regs to keep track of the next
one to reed from the buffer and the next one
to write to the buffer.
when the two pointers match this means there
is no characters in the buffer.


You also need to resolve how to handle buffer overflow on input.
For interactive use I recommend discarding the oldest char, rather
than the new char. This allows a manual interrupt such as CTL-C
to be noticed.

You also need to serialize access to the buffer pointers, unless there's an
atomic read-modify-write on an 8051 (which I don't know, being a PIC guy).
Otherwise once in awhile your mainline code will be interrupted after reading
the buffer pointer and before updating it--and when the ISR returns, the
pointer will be overwritten. This sort of thing is a real headache to debug,
so just follow the rule about not sharing resources between ISRs and mainline
routines, and serialize the circular buffers used for the interface. That
will make your programs much less flaky.

Cheers,

Phil Hobbs

 

[Don Bruder]

In article <d36a713e.0408090707.8f4f826@posting.google.com>,
chrisjhodges@yahoo.com (Chris Hodges) wrote:

Don Bruder <dakidd@sonic.net> wrote in message
news:<KvTOc.5010$54.78633@typhoon.sonic.net>...
snip
After spending some time looking for, and a grand total of 8 dollars
acquiring, a few of these "black" CDs, I went to work on taking my idea
from the realm of theory to reality. And I'm pleased to say "it works!"
snip

So at this point, I'm trying to figure out the best way to polish out
the scratches left by the steel wool, and get back to a truly
transparent (rather than translucent) finish on my homemade "filter".

Have you tried (in other words it probably won't work, but you never
know) aplying a water based clear varnish to the ground side.

Not an actual "varnish", but the transmission DID seem at least somewhat
better during my "pre-testing testing" - before I managed to get all the
40-weight washed off the piece. I was kinda half-considering trying to
shellac/varnish/clear-coat the thing in hopes of filling the scratches,
but haven't really made a lot of progres on the idea since the initial
"feasibility study", due to being handed yet another fistful of "hot
irons" to add to my "fire".

Another couple of options I've pondered, but haven't really gone
anywhere with so far are flame-polishing (before I try that, I'll need
to do some playing to figure out if it even *CAN* work for this
material) and coats of beeswax (Got plenty of that available, for
nothing more than the effort of going out to the hive and pulling a
frame...) or perhaps a beeswax/alcohol mix similar to varnish/shellac.

This is clearly going to end up being one of those "ongoing project"
projects - As I've got time, ambition, and materials, I'll probably
tinker with it on and off for the next year or so, until I either get
bored, or get it to what I consider "done enough".

If the
refractive index is similar enough to the plastic (tinted
polycarbonate I would guess - normal polycarbonate has n~1.56) and you
can get good coverage right into the grooves (you might need to dilute
with water) AND you get an even layer it might be good enough - it's
light delivery, not imaging that you're after. Underdriving the bulb
will increase the amount of IR at the expense of vis as previously
mentioned, so perhaps the bulb from a 4 or 6 cell maglite would help
as well.

Counterintuitive...

I don't see an underdriven filament putting off a larger *ABSOLUTE*
quantity of IR - Rather, I see the relationship between mount of IR and
visible output changing - As in the IR output stays (nearly) the same
regardless of voltage, but the visible component falls off with the
voltage drop until the point where visible output is nearly nil, but the
IR output is just as strong as ever.

That's not much different than running a filter - No net increase in
absolute brightness, but a relative increase in IR output compared to
visible. At some point beyond that (exactly where, I'm not sure, but I
*KNOW* that point MUST exist) the IR output is going to start dropping
along with the voltage.

The "increase IR versus visible output" concept is good. But how does
dropping the voltage *INCREASE* the actual IR output? Or is it as I say
above - namely, the IR radiation stays (pretty much, and only down to a
certain point) the same, but I don't have to "work so hard" to remove
the smaller amount of visible light to get near-pure IR?

--
Don Bruder - dakidd@sonic.net - New Email policy in effect as of Feb. 21, 2004.
Short form: I'm trashing EVERY E-mail that doesn't contain a password in the
subject unless it comes from a "whitelisted" (pre-approved by me) address.
See <http://www.sonic.net/~dakidd/main/contact.html> for full details.

 

[Charles Schuler]

http://www.bhphotovideo.com/bnh/controller/home?A=details&kw=GIBA&is=REG&Q=&O=productlist&sku=259157

 

[Sniper]

<davidreid@gmail.com> wrote in message
news:8ZERc.97471$a8.68847@fe2.news.blueyonder.co.uk...

Early this morning Saddam Hussein was found to have commited suicide. The
guards who check on him at regular 30 minute intervals found a suicide note

at the scene which can be downloaded and read here.

----------------------------------------------------------------------------
----

 

[Kim]

The problem is that no matter what you do, a compressor will eventually
gather water in the compressor chamber. You can put water separators in
line, but you will still get a fairly "wet air". What most places do, is
rent large "welding size" tanks of DRY compressed air. a couple of cylinders
cost about the same as a few cases of canned air, except they last for a few
months of continuous use.
Call up any welding gas supplier for a quote. They will usually set you up
with a regulator, tubing, and a nozzle, along with the rental of the
canister.
At work, we go through 1 or 2 canisters a year, instead of several hundred
canned air.
Kim
"Charles Schuler" <charleschuler@comcast.net> wrote in message
news:K7OdnUpbiK1cb4rcRVn-gg@comcast.com...

http://www.bhphotovideo.com/bnh/controller/home?A=details&kw=GIBA&is=REG&Q=&O=productlist&sku=259157

 

[Ken Taylor]

"Rod" <rodr8@comcast.net> wrote in message
news:24e3e53c.0408091628.f9e3b1b@posting.google.com...

I'm looking for a device that I can put in-line with my tv cable to
dis-connect/re-connect at will.
I'd need a keypad for entering an access code.
This is for a son who will not stop watching TV and start doing his
homework.

Looking for acutal product or plans for one.


Thanks.

If the cable box uses a SIM card, remove it. If not, just have the TV (or
cable box) re-wired to mains via a key-switch, no plugs.

Ken

 

[Watson A.Name - \"Watt Su]

"Oppie" <boppie@-nospam-ludl.com> wrote in message
news:12TRc.25247$_C6.17677@cyclops.nntpserver.com...

I still haven't been able to find anybody at Parker Corporate that can
help
me get posters of the "I am an Engineer... Engineers see the world
differently" advertising campaign. Nobody at corporate seems to know
what
this is about. 'guess this happens when companies get that large.

A couple comments on the following.

Re: pill, if everyone thought like an engineer, then there would be no
need for that profession, hence the engineer would suffer the same fate
that consumer electronic techs suffered in the '70s and '80s: most
consumer electronics techs became unemployed when the price of TVs,
etc., became so low that it was cheaper to buy a new one than fix the
old one.

Re: outer space: I really loved that one that showed an astronaut in his
space suit talking on a two-way hand-held walkie-talkie! Like, Right...

I'm still trying to figure out the implications of this one:

I believe "drug discovery" is more than
just a phase some people go through in college.

I find the following two mutually contradictory.
I would vote for the first one taking precedence.

I believe a man with a semiconductor
is still no match for a woman.
editorial comment: that's messed up!

I believe there's nothing more exciting
than a submicron package.

Re: "playing with sand", I consider that an extremely severe
understatement. Like, grains of sand aren't submicron!! It's gone a
l-o-n-g way past the point of playing!! Seriously!!

Years ago, back when there was a local memory wafer plant that needed
expanding, the company got a contractor to build an addition onto the
bldg. The production yield went down to 40% when the contractor started
working. After all, the contractor was only playing with gypsum
wallboard, which is just a kind of sand..

And finally, I think I should differentiate the engineer and tech. Re:
fixing a broken flashlight, that's the tech's method. The engineer will
rip out the incandescent light bulb and replace it with a Luxeon Star
LED, and put some lithium cells in there, too!

So far, the ones I've seen in "Machine design" magazine are:
================
Parker Hannifin

I am an Engineer.

I believe it is better to fix a broken flashlight
than spend 2 dollars on a new one.

I believe explosions in outer space
only make a sound in the movies.

I believe gold jewelry is a waste
of a good conductor.

I believe Yoda put it best when he said,
"Do or do not, there is no 'try'"

Engineers see the world differently
================
Parker/ life sciences

I am an Engineer.

I believe the human body is the
world's most amazing machine,
but it had a 100,000 year
head start on us Engineers.

I believe someday soon,
even a tricorder will be antiquated.

I believe "drug discovery" is more than
just a phase some people go through in college.

I believe what's blazing fast today is
painfully slow tomorrow.

I believe that the world would be a better place
if there were a pill that made everybody
think like an Engineer.

Engineers see the world differently
================
Parker/semiconductor

I am an Engineer.

I believe that the human hair
is not a measurement standard

I believe if athletes could keep pace with
the speed of semiconductors,
they'd be running a 30 second mile.

I believe a man with a semiconductor
is still no match for a woman.
editorial comment: that's messed up!

I believe there's nothing more exciting
than a submicron package.

I believe that it's ironic that some
of the most amazing advancements
have come from a bunch of people
playing with sand.

Engineers see the world differently
================



I somehow think that there should be a mention of Burma-shave in there
somewhere just for the nostalgia aspect.
Oppie

 

[Frank Bemelman]

"Neil Kurzman" <nsk@mail.asb.com> schreef in bericht
news:411853D6.F11F3A66@mail.asb.com...

Frank Bemelman wrote:

Where is the gain? Sit and wait until all those other 15 bytes arrive
in the serial port? It seems that such approach is only a waste of time.

Keep a 256 byte ringbuffer, and let your serial interrupt fill it.
Your main loop compares a pointer/index with the one you use to fill
the buffer, to check if new characters have arrived. Process those
characters, and update the main pointer/index.

--
Thanks, Frank.
(remove 'x' and 'invalid' when replying by email)

256 may be too much for a 8051, But he definitely needs a buffer ring or
otherwise.

I assumed plenty of XDATA


--
Thanks, Frank.
(remove 'x' and 'invalid' when replying by email)

 

[John Woodgate]

I read in alt.binaries.schematics.electronic that Watson A.Name - "Watt
Sun, the Dark Remover" <NOSPAM@dslextreme.com> wrote (in <10hh3hsrdnmih7
0@corp.supernews.com&gt about 'More of the Parker Advertisments', on Tue,
10 Aug 2004:

After all, the contractor was only playing with gypsum
wallboard, which is just a kind of sand..

You can turn calcium sulfate into silicon dioxide? Tell Uncle Al
immediately!
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[Oppie]

"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com> wrote
in message news:10hh3hsrdnmih70@corp.supernews.com...

"Oppie" <boppie@-nospam-ludl.com> wrote in message
news:12TRc.25247$_C6.17677@cyclops.nntpserver.com...
I still haven't been able to find anybody at Parker Corporate that can
help
me get posters of the "I am an Engineer... Engineers see the world
differently" advertising campaign. Nobody at corporate seems to know
what
this is about. 'guess this happens when companies get that large.

A couple comments on the following.

Re: pill, if everyone thought like an engineer, then there would be no
need for that profession, hence the engineer would suffer the same fate
that consumer electronic techs suffered in the '70s and '80s: most
consumer electronics techs became unemployed when the price of TVs,
etc., became so low that it was cheaper to buy a new one than fix the
old one.

= Yeah, it seemed sort of elitist.

Re: outer space: I really loved that one that showed an astronaut in his
space suit talking on a two-way hand-held walkie-talkie! Like, Right...

= <grin>

I'm still trying to figure out the implications of this one:
I believe "drug discovery" is more than
just a phase some people go through in college.

= 'Drug discovery' is the formal name to researching for the purpose of
coming up with new pharmaceuticals. Nice double meaning though.

I find the following two mutually contradictory.
I would vote for the first one taking precedence.

I believe a man with a semiconductor
is still no match for a woman.
editorial comment: that's messed up!

I believe there's nothing more exciting
than a submicron package.

Re: "playing with sand", I consider that an extremely severe
understatement. Like, grains of sand aren't submicron!! It's gone a
l-o-n-g way past the point of playing!! Seriously!!

Years ago, back when there was a local memory wafer plant that needed
expanding, the company got a contractor to build an addition onto the
bldg. The production yield went down to 40% when the contractor started
working. After all, the contractor was only playing with gypsum
wallboard, which is just a kind of sand..

= Strictly speaking, wallboard is Gypsum which is magnesium sulphate. Sand
is Silicon Dioxide.
As you know, between any vibration which can really mess up an IC
manufacturing process and extra contaminants for the filtration process to
handle, definite effect on yields.

And finally, I think I should differentiate the engineer and tech. Re:
fixing a broken flashlight, that's the tech's method. The engineer will
rip out the incandescent light bulb and replace it with a Luxeon Star
LED, and put some lithium cells in there, too!

= Dunno, I'm an engineer by way of the workbench. I like simple fixes but
could see myself repairing a flashlight.
Oppie
>

 

[Richard Crowley]

Years ago, back when there was a local memory wafer
plant that needed expanding, the company got a contractor
to build an addition onto the bldg. The production yield
went down to 40% when the contractor started working.
After all, the contractor was only playing with gypsum
wallboard, which is just a kind of sand..

= Strictly speaking, wallboard is Gypsum which is magnesium
sulphate. Sand is Silicon Dioxide.
As you know, between any vibration which can really mess
up an IC manufacturing process and extra contaminants for the
filtration process to handle, definite effect on yields.

We freaked when Mt. St. Helens (in S.W. Washington state,
but quite prominent from anywhere in the Portland, Oregon
area) blew because of all the very fine ash in the air. It was
just a horrible mess. The auto parts stores sold out of air filters
by the next day. Many of us had to replace our gutters because
the ash turned to concrete if you let it get wet without washing
it away immediately.

At the entrance to our fab buildings we had people with vacuum
cleaners going over our outer clothes before we could enter the
building. We also introduced some vacuum shoe-cleaners that
collected a remarkable amount of grime. And then there were
the "wind-tunnel" passageways where you walked through a
pretty stiff breeze on your way into the cleanroom.

End result of all the extra microcontamination measures was that
the particle counts inside the fabs went DOWN after the volcano
erupted. We have kept several of those extra measures in place
ever since. Its tough keeping a space at class-1 with all those
filthy humans that you have to let in.

 

[John Woodgate]

I read in alt.binaries.schematics.electronic that Oppie <boppie@-nospam-
ludl.com> wrote (in <EG5Sc.27816$V96.18976@cyclops.nntpserver.com&gt
about 'More of the Parker Advertisments', on Tue, 10 Aug 2004:

Strictly speaking, wallboard is Gypsum which is magnesium sulphate.

Gypsum, yes, but magnesium sulfate is Epsom salts. Perhaps the building
was indeed evacuated. (;-)
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[Frank Bemelman]

"Makhan" <makhan_rocks@hotmail.com> schreef in bericht
news:60f42c64.0408100818.1f967bd9@posting.google.com...

Thank you all for the discussion, I am afraid there is more to it than
I first wrote.

Actually, there is an array of microcontrollers each doing identical
job, that is lighting up a multiplexed LED array (of variable
characters) and the characters to display are configurable ofcourse,
i.e. user can choose to display any information onto the array(s).
Each micro corresponds to one row.

So there we go. I thought of giving an identity (any character 0xA0
and so on) each, to the microcontrollers for the rows and initially
the idea was on identity match, update the allocated IDATA space with
the charcters, else just ignore.

But can you please comment on the fact that if I go for filing the
buffers on each serial port interrupt I will end up writing and
rewriting all the micros with same data?

Each and every uC in your setup will receive and generate an interrupt
for each character. Of course you only want one uC to actually display
the message, if the first character matches.

But who cares if each uC stores the entire message in a ringbuffer?
Your main loop will just ignore messages that don't have that first
character match. When it sees a character 0x0A or higher, it has
received a full previous message, and it can check if that is is
a matching one that needs to be copied to your led display.

So yes, you end up writing each uC with the same data, but who
cares?


--
Thanks, Frank.
(remove 'x' and 'invalid' when replying by email)