20 Apr
2012
20 Apr
'12
10:52 a.m.
A metal-film resistor, used
below its ratings, will outlive any microcotnroller.
-tony
Well maybe (though no guarantee there), but the 555 would likely have the
same sort of lifetime as a microcontroller - arguably poorer.
Bob
20 Apr
20 Apr
11:04 a.m.
On 4/20/2012 11:52 AM, Robert Adamson wrote:
Well maybe (though no guarantee there), but the 555
would likely have the
same sort of lifetime as a microcontroller - arguably poorer.
That is 30 seconds. Wait, I guess we are not discussing marketing.
I would go with the 555 timer, the Arduino could be running near its
max clock freq.
Bob
Ben.
12:19 p.m.
ben wrote:
On 4/20/2012 11:52 AM, Robert Adamson wrote:
The discussion is almost nonsense :-)
There is no Application jou can just build out of a 555 nor there is one
that only uses a micro. So what?
I'm thinkering to build an small Epromer for just one single sort
of Eproms (Am27C291/CY7C291..) and I'm desingning in a ?A723 currently.
What about his chip? It is old like stoneage and still in production..
Unfortunately I'm unable to emulate it's functionality with the Amtega32
that will be go in that promer (No, Im not going to build an buck converter
out of an Atmega Timer), but for sure I'm generating the program
pulse length not with a 555...
Regards,
Holm
--
Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe,
Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741
Well maybe (though no guarantee there), but the
555 would likely have the
same sort of lifetime as a microcontroller - arguably poorer.
That is 30 seconds. Wait, I guess we are not discussing marketing.
I would go with the 555 timer, the Arduino could be running near its
max clock freq.
Bob
Ben.
1:26 p.m.
William Donzelli wrote:
...hmm... such ones that put out a bunch of 555's instead of exploding?
Think you would need at least a battery, resistors, some sensor, an
actuator or some glow device ...endless things that can fail.
There are already constructions w/o the need of any electrics at all.
Next, I wouldn't build duch an device, I'm a pacifist (mostly). You are an
American? I've learned that such things tend to not solve problems,
they build other, bigger problems, so you need A Bombs then, wich tend to
not solve problems...
The discussion
is almost nonsense :-)
There is no Application jou can just build out of a 555
Land mines.
or there is one
Same here, may be my 6 year old son is suprised a little if I give him
an old 8742 to play with (and to look in it).....
Regards,
Holm
--
Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe,
Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741
that only uses a micro.
Children's toys. 
21 Apr
21 Apr
12:16 p.m.
The discussion is almost nonsense :-)
There is no Application jou can just build out of a 555
Land mines.
or there is one
These being for children who have some kind of electronic interface built
in that direclty conencts to the I/O pins on the microcotnroller?
-tony
that only uses a micro.
Children's toys. 
20 Apr
20 Apr
3:13 p.m.
On 20 Apr 2012 at 21:19, Holm Tiffe wrote:
There is no Application jou can just build out of a
555 nor there is
one that only uses a micro. So what?
Is that true? I routinely use an 8-pin PIC to develop a READY/
signal from the INDEX/ signal on a floppy drive. Other than +5 for
power supply, it requires no components. I could have done the same
thing with a 555 or two, but I'd have to add R and C to make it work.
That same PIC could potentially serve as a timer with a period in
centuries without any external components--something an 555 could not
do.
--Chuck
3:31 p.m.
Chuck Guzis wrote:
On 20 Apr 2012 at 21:19, Holm Tiffe wrote:
YES!
What I wanted to say no 555 and mo micro alone can do anything.
There where other parts to add some functionality. It depends on energy at
least to do something. It isn't relevat if there is a 555 or a micro, alone
they make pretty little bugs that sit on the table...
Regards,
Holm
There is no Application jou can just build out of
a 555 nor there is
one that only uses a micro. So what?
Is that true? I routinely use an 8-pin PIC to develop a READY/
signal from the INDEX/ signal on a floppy drive. Other than +5 for
power supply, it requires no components. I could have done the same
thing with a 555 or two, but I'd have to add R and C to make it work.
That same PIC could potentially serve as a timer with a period in
centuries without any external components--something an 555 could not
do.
--Chuck
--
Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe,
Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741
4:50 p.m.
On 21 Apr 2012 at 0:31, Holm Tiffe wrote:
What I wanted to say no 555 and mo micro alone can do
anything. There
where other parts to add some functionality. It depends on energy at
least to do something. It isn't relevat if there is a 555 or a micro,
alone they make pretty little bugs that sit on the table...
Isn't that a bit of a straw man argument? What bit of electronic
paraphenalia can do anything without some energy input? For that
matter, what bit of any device, yourself included, can do anything
without energy input?
Without energy, you're food for the worms (which depend on you for
their energy).
--Chuck
10:57 p.m.
See sure the 555 can do it
http://hackaday.com/tag/555/
one seems to be building the computer from the 555's
Dave Caroline
11:26 p.m.
On 04/21/2012 01:57 AM, Dave Caroline wrote:
See sure the 555 can do it
http://hackaday.com/tag/555/
one seems to be building the computer from the 555's
A absolutely LOVE the 555 footstool on that page!
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
21 Apr
21 Apr
9:43 a.m.
"To a man with a hammer, the whole world looks like a . . . "
THUMB.
If I needed to build a doorbell controller TODAY, it would be quicker,
easier (and CHEAPER) for me to build it out of a 5170 than a 555 or
Arduino.
But it would be embarrassing.
10:18 a.m.
On Sat, 21 Apr 2012, Chuck Guzis wrote:
On 21 Apr 2012 at 9:43, Fred Cisin wrote:
A button.
g.
--
Proud owner of F-15C 80-0007
http://www.f15sim.com - The only one of its kind.
http://www.diy-cockpits.org/coll - Go Collimated or Go Home.
Some people collect things for a hobby. Geeks collect hobbies.
ScarletDME - The red hot Data Management Environment
A Multi-Value database for the masses, not the classes.
http://www.scarletdme.org - Get it _today_!
Buying desktop hardware and installing a server OS doesn't make a
server-class system any more than sitting in a puddle makes you a duck.
[Cipher in a.s.r]
If I needed to build a doorbell controller TODAY,
it would be quicker,
easier (and CHEAPER) for me to build it out of a 5170 than a 555 or
Arduino. But it would be embarrassing.
What's a "doorbell controller"?
4:09 p.m.
What's a
"doorbell controller"?
A momnetary-actionm push-to-make (form A) single
pole switch? I haev a
couple of new ones hwere with Heath/Zentih logos on the packaging...
22 Apr
22 Apr
11:39 a.m.
What's a "doorbell controller"?
A momnetary-actionm push-to-make
(form A) single pole switch? I haev a
couple of new ones hwere with Heath/Zentih logos on the packaging...
21 Apr
21 Apr
1:16 p.m.
If I needed to build a doorbell controller TODAY, it
would be quicker,
easier (and CHEAPER) for me to build it out of a 5170 than a 555 or
Arduino.
But it would be embarrassing.
Wouldn't it be easier to use a 5150? You've got the cassette motor relay
which you could then use energise the bell.
-tony
4:13 p.m.
> If I needed to build a doorbell controller TODAY,
it would be quicker,
> easier (and CHEAPER) for me to build it out of a 5170 than a 555 or
> Arduino.
> But it would be embarrassing.
On Sat, 21 Apr 2012, Tony Duell wrote:
Wouldn't it be easier to use a 5150? You've
got the cassette motor relay
which you could then use energise the bell.
It would, indeed, be far preferable. (and was what I had in mind)
But the supply of them is dwindling. I only have one left!
22 Apr
22 Apr
11:43 a.m.
[Doorbell controller]
OK, use a CPjr, then. I think that has a motor relay...
Hang on... The 5170 floppy drive has a head load solenoid. The driver for
that much be able to sink enough current to fire a relay. So you cna use
a 5170, and just kludge a small relay into the floppy drive...
I suspect you could easily add a relay drive to one of the keyboard IEDs.
Rignt the doorbell on CAPS LOCK or something....
[Yes, I am well aware how to drive relays from TTL or RS232 level signsl.
I am just tryign to avoid suggsting it...]
-tony
Wouldn't
it be easier to use a 5150? You've got the cassette motor relay
which you could then use energise the bell.
It would, indeed, be far preferable. (and was what I had in mind)
But the supply of them is dwindling. I only have one left!
21 Apr
21 Apr
12:29 p.m.
On 20 Apr 2012 at 21:19, Holm Tiffe wrote:
YEs it does! It requires the components on the floppy drive logic board.
More seriosuly, how do you drive the Ready/ pin on the itneface
conenctor? Can the microcontroller sink enough current? and how do you
gate it with the drive select? If you're doing it i nthe microcontroller,
i can see problems with some controllers that poll the drivses repeatedly
looking for a change of state of the ready/ line.
There is no Application jou can just build out of
a 555 nor there is
one that only uses a micro. So what?
Is that true? I routinely use an 8-pin PIC to develop a READY/
signal from the INDEX/ signal on a floppy drive. Other than +5 for
power supply, it requires no components. I could have done the same thing with a 555 or two, but I'd have to add R and
C to make it work.
Unless you stick a copy of the PCI source code ot every drive chassis, I
know which I'd rather be faced with...
-tony
2:51 p.m.
On 21 Apr 2012 at 20:29, Tony Duell wrote:
More seriosuly, how do you drive the Ready/ pin on the
itneface
conenctor? Can the microcontroller sink enough current? and how do you
gate it with the drive select? If you're doing it i nthe
microcontroller, i can see problems with some controllers that poll
the drivses repeatedly looking for a change of state of the ready/
line.
48 ma enough? I've got 8 pins, 5 of which are programmable high-
impedance/input/output and one of which is dedicated input.
Unless you stick a copy of the PCI source code ot
every drive chassis,
I know which I'd rather be faced with...
At my age, I'll be dead before I need to revisit the code. Still,
the code is small enough that I could probably stick an optically-
readable bit of bar code on it. Of course, the datasheet for the
drive will long have disappeared into the internet netherworld.
--Chuck
22 Apr
22 Apr
11:31 a.m.
On 21 Apr 2012 at 20:29, Tony Duell wrote:
I do ahve a sligth moral objection to driving na interfce pin from a
custom or programmed IC. I know just about all reasonably-recent drvies
do it, but I still don;t like it. Too easy to zzap things. And for the
cost of a '38, it's trivial to avoid...
You ahven't expalined how you gate the ready/ signal with DS/. I assume
you feed DS/ into the PIC too (If you take it driectly from the interface
conencotor or the selct link, I wonder if the pCI has the correct input
threshold :-)). I am still worried if the PIC is fast enough to turn
ready/ on and off in all cases.
More seriosuly, how do you drive the Ready/ pin
on the itneface
conenctor? Can the microcontroller sink enough current? and how do you
gate it with the drive select? If you're doing it i nthe
microcontroller, i can see problems with some controllers that poll
the drivses repeatedly looking for a change of state of the ready/
line.
48 ma enough? I've got 8 pins, 5 of which are programmable high-
impedance/input/output and one of which is dedicated input. At my age, I'll be dead before I need to revisit
the code. Still,
Yes, but your descentants may have to fix it :-).
-tony
1:53 p.m.
On 22 Apr 2012 at 19:31, Tony Duell wrote:
At less than USD$1.00 for a PIC, it's hard to rationalize on a faint
possibility. It works.
--Chuck
On 21 Apr 2012 at 20:29, Tony Duell wrote:
I do ahve a sligth moral objection to driving na interfce pin from a
custom or programmed IC. I know just about all reasonably-recent
drvies do it, but I still don;t like it. Too easy to zzap things. And
for the cost of a '38, it's trivial to avoid... More seriosuly, how do you drive the Ready/ pin
on the itneface
conenctor? Can the microcontroller sink enough current? and how do
you gate it with the drive select? If you're doing it i nthe
microcontroller, i can see problems with some controllers that
poll the drivses repeatedly looking for a change of state of the
ready/ line.
48 ma enough? I've got 8 pins, 5 of which are programmable high-
impedance/input/output and one of which is dedicated input.
23 Apr
23 Apr
11:10 a.m.
At less than USD$1.00 for a PIC, it's hard to
rationalize on a faint
possibility. It works.
And that sums up what I hate about most modern stuff...
If you add the '38, OK, you multiply the overall cost by 2 or 3 times.
But you get a deivce that when it gets zapped, can be repaired by finding
a '38 in the junk box,or in the local electroncis shop and about 5
minutes of soldering. As opposed to having to find a PIC (which the local
electronics shope probably doesn't stcok), then having to get the ROM
image from somewhere, and having to program it.
Paying extra at the start for standard I/O buffers is well worth it to me.
-tony
2:01 p.m.
On 23 Apr 2012 at 19:10, Tony Duell wrote:
Since it's not for anyone's use by my own, I figure a tube of PICs is
about the right amount of backup. I still have new bipolar PROMs and
RAM as well as all sorts of chips that I'll never find a use for, at
least in the replacement sense, not to mention doodads such as tunnel
diodes.
If I had to design a replacement, I could even do it with discretes--
assuming that the local shop even knows what a junction transistor is
at that point. Assuming, at that point, that I still have my
faculties. If not, I won't care anyway.
--Chuck
At less than
USD$1.00 for a PIC, it's hard to rationalize on a faint
possibility. It works.
And that sums up what I hate about most modern stuff...
If you add the '38, OK, you multiply the overall cost by 2 or 3 times.
But you get a deivce that when it gets zapped, can be repaired by
finding a '38 in the junk box,or in the local electroncis shop and
about 5 minutes of soldering. As opposed to having to find a PIC
(which the local electronics shope probably doesn't stcok), then
having to get the ROM image from somewhere, and having to program it. 
20 Apr
20 Apr
4:45 p.m.
On 04/20/2012 02:19 PM, Holm Tiffe wrote:
There is no Application jou can just build out of a
555
You can use them as an alarm system, scattering them upside-down around the
fridge, for detecting when kids in bare feet sneak downstairs for a
midnight snack... ;-)
cheers
Jules
4:47 p.m.
On Apr 20, 2012, at 7:45 PM, Jules Richardson wrote:
On 04/20/2012 02:19 PM, Holm Tiffe wrote:
True, but LEGOs are much cheaper. :-)
(at least if you get them in bulk)
- Dave
There is no Application jou can just build out of
a 555
You can use them as an alarm system, scattering them upside-down around the fridge, for
detecting when kids in bare feet sneak downstairs for a midnight snack... ;-)
21 Apr
21 Apr
12:41 p.m.
>> There is no Application jou can just build
out of a 555
Your applicaiton nbeeds several 555s, not one :-)
You can use them as an alarm system, scattering them upside-down
around the
fridge, for detecting when kids in bare feet sneak downstairs
for a midnight snack... ;-)
True, but LEGOs are much cheaper. :-)
I am nto totlally convinced of that, based on the prices that Lego and
555s seem to sell for,
I rememebr many years ago being in Maplin in Bristol when a lady asled
for 'a couple of your smallest chips, I don't care what they do'. It
turned out she was a sculptress (or some similar artist) and needed them
for that sort of work.
I can't remembr if 741s or 555s were cheaper at the time eitehr :-). I do
rememebr dgetting a large box of defective ICs sent to her from the lab,
though.
-tony
12:02 p.m.
I'm thinkering to build an small Epromer for just
one single sort
of Eproms (Am27C291/CY7C291..) and I'm desingning in a =B5A723 currently.
What about his chip? It is old like stoneage and still in production..
I was amazed to discover there's even an RoHS-compliant version of the
TO110 (10 lead metal can) one. I needed to repalce such a device on a PCB
that had 10 pads in a circle (so kludging the DIL version in would haev
been a problem). It wasn't cheap, but at least I could stil lget it.
Oh, the device.... An HP11305 disk controller for the HP9830. One day
I'll get the 'cable' to link the computer nad controller and then I can
really have some fun.
Unfortunately I'm unable to emulate it's
functionality with the Amtega32
that will be go in that promer (No, Im not going to build an buck convert=
er
out of an Atmega Timer), but for sure I'm generating the program
pulse length not with a 555...
My first EPROM programmer, which I built about 25 years ago couldn't yse
a microcontrolelr or even a microprocessor. There were no
microcontrolelrs abck then that you could program with an SPI or JTAG
interfave, they all programemd a bit like EPROMs. And of course if I'd
used a microprocessor I'd haev needed an EPROM to store the cotnrol
program. The problem being that without a programmmer, there was no way
for me to program that EPROM or microcontroller...
Anywy, it ended up as a couple of boars of logic ICs. I think I used a
74121 to generate the programming pulse. Not having a logic analyser at
the time, or even a well-calibrated 'scope, I set the pusle width by
clocking the input to the '121 at a known frequency (I think I divided
down a crystal) and measured the duty cycle of the output by the simple
method of measuring the average voltage there.
Amazingly the thing worked, I prgrammed many EPROMs on it...
-tony
20 Apr
20 Apr
12:03 p.m.
A metal-film resistor, used
below its ratings, will outlive any microcotnroller.
-tony
Well maybe (though no guarantee there), but the 555 would likely have the
same sort of lifetime as a microcontroller - arguably poorer. 
12:49 p.m.
Tony Duell wrote:
Why?
My expeirence is that more compelx ICs are noticably less reliable than
simple ones. An IC (of any complexity) is more reliable that making the
same circuit from discrete components or simpler ICs, but that's not the
issue.
I would think the 555 had a much better lifetime than any microcontrolelr
therefore.
The origianl 555 (as opposed to the 7555, etc) is large-ish junciton
bipolar and thus less likely to suffer static damage than a MOS
microcotnroller. It also has a much wider supply votaeg range and is less
likely to be damaged by supply problems.
And of coruse if a microcontroller fails, unless you have the program to
put into it, you're stuck. If a 555 fails, well, there's a tube of 50 in
my spares box. And I cna go to any number of suppliers anf buy one.
-tony
I'm with Tony here - consider this, the number of components on a 555
die vs the Aurdino are orders of magnitude less, and the size is much
larger for the 555 elements.
Cosmic radiation is one of the main causes of electronic failures, thus
a part with larger elements and fewer bits is going to be more reliable.
In my field we service video games from the early 70s (and up) - and
555s are amongst the most reliable parts found - far more reliable than
CPUs (1980s) for example...
John :-#)#
A metal-film resistor, used
below its ratings, will outlive any microcotnroller.
-tony
Well maybe (though no guarantee there), but the 555 would likely have the
same sort of lifetime as a microcontroller - arguably poorer.
12:39 p.m.
Well maybe (though no guarantee there), but the 555
would likely have the
same sort of lifetime as a microcontroller - arguably poorer.
Considering how many die shrinks and process refinements the 555 has gone
through, I would say poorer, and by quite a bit. Today's 555, or maybe even
ones ten years old or more, are made to *just* meet all the published
specifications, and *nothing* more. With low value, high volume parts like
the 555, shaving fractions of a percent can save a lot of money in the long
term.
With a fairly young design, like a modern microcontroller, it pays to make
them some amount better than the specs, because the fabs can always refine
the chip later to shave those costs.
As for metal film resistors - just the fact that they exist on the board
makes them unreliable and yield killing. Old saying - the most reliable
parts are the ones that are not there.
--
Will
21 Apr
21 Apr
12:14 p.m.
As for metal film resistors - just the fact that they
exist on the board
makes them unreliable and yield killing. Old saying - the most reliable
parts are the ones that are not there.
That has to rate as one of the most stupid thigns I have ever read.. It
is wrong on so many levels...
I cna think of many times when removing components reduces reliability.
Setting aisde the 'sillies' -- like removing a zener diode so the PSU
output goes sky-high and ruins all the ICs, consider compoents designed
to protect the device from transients on input lines. Without them, the
device might well work fine for many months, then ther'es an
inductively-coupled spike on one of the cables and bye-bye expensive IC.
Alternatively, you may add extra compopnents so that they all work within
their design ratings. I will accept that 2 resistors in series are less
reliable than a single reissotr. But the startup resisotr in most SMPSUs
does consist of a 2 components in seires. They're often around 100k a
time. This is not for power disipation reasons, it's because there is a
maximum voltage tyhat resisotrs will withstand. And it would be exceeded
by the votlage acrss the startup rsistor. I gues there are speical HV
reisusotrs, but they are not common and rarely used here.
In fact a logical corrollery of minimising the component count would be
to remoove all crowbar circuits. After all, they do nothing most of the
time, and they can malfucntion and trip in error, But I am sure glad
they're there when needed.
Or remocving other safety circuits. My laser printer has a fairly complex
circuit to prevent the fuser from overheating if soemthing fails inthe
control system. In fact, it's malfunctioning at the momnet, and in that
sense it's unrelaible, but I am certainly not going to improve
reliability by permanently disabling it.
The other heing is that not all components are equally reliable. I think
we would all agree that thigns with mechanical contacts --connectors,
switches and relays are a lot less reliable than semiconductors. And that
electrolytic capacitors, for all I don't beleive the witch-hunt normally
directed against them, are lses reliable thean polystyrene capacitors.
Now, my expeirenice, gained form working on many thousands of devices
over the last 40 years is that complex ICs are noticeably less reliable
than simpler ones. Microprocessors and microcontrollers do fail more
often than 555s. And metal film reissotrs hardly ever fail.
-tony
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