Driver to drive?

In <YvUHd.215201$r4.12355307@news-reader.eresmas.com>, on 01/20/05
at 08:01 PM, Jose Maria Lopez Hernandez <jkerouac@bgsec.com> said:



Talking seriously, death penalty makes USA a third-world country. Until
you stop *murdering* people that way no one will consider USA a
civilizated country.

We don't give a crap what you think of our country. We don't need you, but
history has shown that you need us.
 
Chris Graham wrote:

I'm designing a product that includes a number of interchangable boards that
give various capabilities, each with its own small microcontroller and
sensors/actuators. Any modules in a system would be connected to a more
powerful main board (basically the reference design of a PDA). It must be
easy for the user to open the box and plug in new modules, or plug them into
sites on the outside, and also for third parties to provide modules that
also plug in.
I'd take a hotplug controller for the power and perhaps LVDS
for the unidirectional data channels.

Rene
--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net
 
Chris Graham wrote:
I'm designing a product that includes a number of interchangable
boards

I was designing my own interconnect standard that included power
and bidirectional data lines (ideally at least1mbps), maybe based
on RS485, and a way for devices to announce their type and capabilities.
As I worked on the design I started to realize I was reinventing USB.
....

I was hoping this group could give me a sanity check before I
proceed to design a system based on USB.
Look here: http://www.usb.org/developers/onthego/

--
Guy Macon <http://www.guymacon.com/>
 
On Thu, 20 Jan 2005 13:29:56 -0500, "Aunty Kreist"
<Aunty_Kreist@satanickittens.net> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:lmqvu0tder92bb9bisb4ivtnlbrcglleu2@4ax.com...
On Thu, 20 Jan 2005 09:33:09 -0600, "Rhyanon" <pissoff@uberbitch.com
wrote:

Such talk from a chreeshtun! Your gawd would damn you to hell, if it or
gawd actually existed. Lucky for you!

---
So, cRHYbaby, if God existed, _you'd_ be making rules for It?

--
John Fields

Uh....aren't you the fool that just posted this in our group?

What Is God?

God is the creator of our universe.

~~~~~~~~~~~

So why are you trolling in ARW, but pretending something else when your own
"group" can see you?
---
You really _are_ thick, aren't you?

I believe God exists, but Rhyanon apparently doesn't, therefore from
Rhyanon's statement about what God would do to me if He existed,
Rhyanon is making rules which, if God existed, God would have to
follow.

Got it?

--
John Fields
 
On Thu, 20 Jan 2005 13:43:56 -0500, "Aunty Kreist"
<Aunty_Kreist@satanickittens.net> wrote:

"Reg Edwards" <g4fgq.regp@ZZZbtinternet.com> wrote in message
news:csnt0v$d8h$1@hercules.btinternet.com...
Proof? I expect you to give cites.

======================

How can cites provide proofs?

They are merely yet more opinions, no more reliable than the person who
didn't quote one.

Often more unreliable because of being taken out of context or misquoted.

Either you accept a statement or you dont accept it.


John has this habit of informing people what they believe. It's very kind of
him.

---
Yes, tell me what you believe and I'll inform you that that's what you
believe. Boy, it's not hard to get you cretins riled up to the point
where you'll just fire anything off, is it?

--
John Fields
 
I read in sci.electronics.design that John Fields <jfields@austininstrum
ents.com> wrote (in <ik60v05pjc0hs834ar5hf33ra4pnctfgro@4ax.com>) about
'Peterson's Death Sentence', on Thu, 20 Jan 2005:

BTW, have you got a clue about the origin of the universe?
It's at the point (0,0,0,0,0,0,0,0,0,0,0).
--
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
 
In article <g560v0ta6itrsdieqasotnir7i9hi0nhk1@4ax.com>,
jfields@austininstruments.com (John Fields) writes:

I believe God exists, but Rhyanon apparently doesn't, therefore from
Rhyanon's statement about what God would do to me if He existed,
Rhyanon is making rules which, if God existed, God would have to
follow.
A zealot is someone who does what God would do if He had all the facts.

--
/~\ cgibbs@kltpzyxm.invalid (Charlie Gibbs)
\ / I'm really at ac.dekanfrus if you read it the right way.
X Top-posted messages will probably be ignored. See RFC1855.
/ \ HTML will DEFINITELY be ignored. Join the ASCII ribbon campaign!
 
I read in sci.electronics.design that uvcceet@juno.com wrote (in
<41f01908$3$woehfu$mr2ice@news.aros.net>) about 'What Is God?', on Thu,
20 Jan 2005:

Oh brother.... If there is no superior being, whence commeth the basic
rights of living? If my right to be free and live as I choose comes from
another human, then that right can be revoked.
It doesn't come from ONE human but from the SOCIETY in which you live.
Societies that practised human sacrifice were quite willing to revoke
selectively the right to live. Societies that practised slavery,
especially galley slavery, were quite willing to revoke individual
freedom.

These days, societies revoke freedom, and life in some cases, by
'judicial process', which is just another society artefact. Courtroom
histrionics instead of trial by ordeal.

If you are imprisoned, will your god get you out?

If I am only allowed to
live because someone else says its okay, how long till that right is
taken away as well.
No-one knows. You hope your kids won't pass a compulsory euthanasia law
when they are running the show.
Governments exist to insure rights, not to grant them. No God... No
rights.
Which god is this? Can you get personalised certificates of your human
rights for an appropriate fee, often called a 'tithe'?
--
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
 
Aunty Kreist wrote:
John Fields wrote...

Aunty Kreist wrote:

John Fields wrote...

Clint Clark wrote:

What Is God?

God is the creator of our universe.

Prove it.

Disprove it.

The burden of the proof is on you. You claimed it as fact.
Now pony up, boi.
If there is a God, why does he ignore my plea that you people
move these discussions to an appropriate newsgroup?

Since January first, I have had to add the following words
to my killfile for sci.electronics.design:

alcohol
alpha centauri
arafat
bookcase
bovril
bush
business
cartoon
circumcision
clinton
coalition
congress
dbade
death sentence
desk
disaster
dubbya
fallujah
foxpro
free will
genome
god
google
inauguration
metaphysical
nazi
nouveau
parents
parrot
political
president
religion
tingling sensation
troops
tsunami
virus
woodgate

...and I just added "god"

In addition, I have over 50 email addresses in my
killfile of posters who *never* write anything
about electronics design - the above listonly
reflects post from those who sometimes write
about electronics design.

What kind of god would allow this without smiting
you people for posting your off-topic flamebait in
an engineering newsgroup?

(Don't bother answering - my killfile will filter it out)
 
Kevin wrote:
Hi Group,

Let me pick your collective brains to see if I'm on the right track
here:

The situation:
I'm designing a microcontroller-based data logger (don't yawn...yet)
that will interface to a piece of equipment and keep track of when
certain events occur. These details are kept in microcontroller ram
and must be maintained even through power loss / daily shutdown
without corruption or loss of data.

Microcontroller is the ever popular PIC16LF628A (Nanowatt/low voltage)
using the 4 MHz Internal RC oscillator. I also plan to use a 32.768
KHz watch crystal to drive Timer1 so that the PIC can periodically
wake and check if power has returned and resume normal operation. I
need to preserve data in the PIC's ram during a power failure but due
to reliability concerns I think powering the PIC from battery during
loss of power is the safest solution versus using EEPROM etc.

I plan to power the PIC16LF628A using power from both the machine
(tapping into 12VDC power and regulating that to 3.3V for
power/charging) as well as a rechargeable lithium 3V battery (see
crude ASCII schematic below):

1N5817
IN4001 3.3V Reg Schottky Diode
12V *--->|---+----[LM2950-3.3]--->|-----------+------+----- To PIC VDD
from | | | |
equipment | | | |
| | \ | +
| | 390 / |
==== 220uF | Ohms \ ==== 33uF
16V | / 6V
==== | | ==== Electrolytic
| | Panasonic ----- |
| | ML1220 battery --- |
| | 17 mAH 3V | |
| | | |
GND *--------+---------+----------------------+------+
from
equipment

1. Any recommendation for the Schottky diode? (through hole package -
no SMD parts). I'm thinking of something with a low Vf (so far the
best I've come up with is a 1N5817 - approx 0.4V) but are there any
other concerns I should be aware of?
The battery spec sheet mentions the charging voltage range should be
2.8V to 3.2V to achieve the rated mAH capacity. (I am pretty close to
the low side of this range as 3.3 - 0.4 = 2.8V). If I could use a
diode with a lower Vf it would help raise the charging voltage.

2. Although it's not on the schematic above I plan to detect whether
12V is present via an 4n25 optoisolator & zener diode ("power fail
signal") to determine whether power is failing/failed (and if so go to
sleep). As stated above the PIC will periodically wake from sleep and
check if power has returned (so it can continue monitoring). This
sounds reasonable, right?

3. Should I be concerned about leakage from the 1N5817 diode when 12V
is absent and the PIC is on battery power? If this leakage is a
problem then what other charging circuit design should I use? I'd like
to keep things simple and use only fairly common inexpensive parts
(nothing that you couldn't get from Digikey). Similarly, would leakage
from the 33uF cap pose a problem?

4. Another thing I'm concerned about is battery life regarding
charge/discharge cycles. The battery specs list these as 1000 cycles.
Now the application shouldn't even remotely come close to draining the
battery in daily usage but I'm just wondering about this. (I
understand that the datasheet is probably on the conservative side).
An alternative might be one of those large close-to-a-farad supercaps
but again I don't know how long the PIC will run off of one of these.

5. Because the PIC Vdd voltage is 3.3v input PIC pins will no longer
be to TTL specs in terms of voltage levels, correct?

6. Finally, is there anything I might have missed with regards to low
power design? (Already checked PIClist.com & read Microchip's "Power
Managed Tips N Tricks" app note (41200B).

Thanks for your assistance.

Kevin.
I'm too lazy to look up the spec. Don't all recent PICs have flash memory?
Does the thing have to log while the power is off? If not, might think
about using a super-cap.


Can you use a fet in place of the diode and run the gate off 12V?
mike

--
Return address is VALID.
Wanted, PCMCIA SCSI Card for HP m820 CDRW.
FS 500MHz Tek DSOscilloscope TDS540 Make Offer
http://nm7u.tripod.com/homepage/te.html
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Bunch of stuff For Sale and Wanted at the link below.
http://www.geocities.com/SiliconValley/Monitor/4710/
 
Paul Burke wrote:
Reg Edwards wrote:

Everybody who supports the death penalty should be shot.


======================

By who ?


By people who can use the correct form for the ablative.

paul Burke
mmmm

Cheers
Terry
 
Rich,

From what I understand, PWM frequency should be around 20kHz to start.
Why do you suggest so low? Why are some people saying to try higher
than where I am at, and some are saying low? There is no set "right
way" I suppose?

The motor driver that the motor company sells and recommends runs at
50kHz. Unfortunately the size and cost rule it out.

I found a formula on the web for calculating winding losses that is as
follows:

Pr = (RT^2Vs^2)/(48L^2) = (RVs^2)/(48L^2) * (1)/(Fs^2)

where Pr is the loss (in Watts), R is the winding resistance (in Ohms),
T is the period (in seconds), Vs is the supply voltage (in volts), L is
the inductance (in Henry's), and Fs is the PWM frequency (in Hz).

Assuming this formula to be true for the amount of power lost in the
windings (generating heat), it can be seen that there are two ways to
reduce this power loss (heat): by raising the PWM frequency, or by
raising the inductance. This is the reason that I want to do one or
the other, however, Rich, you indicate that a lower frequency might
solve my heat issues? It seems that it would be generating more power
loss, i.e., heat?
I'm getting more and more confused!

Any further thoughts?
 
I get a feeling that maybe, your CV isn't putting you in the best light.
Despite some qualms expressed in this NG on my English skills, I am
actually rather good at CV's. Overall, agencies show an amazing amount of
respect for mine. If you want, you could email me yours and I could give a
second opinion on it.
Okay well don't bandy it about the place (I like to hide my true identity!)
but you can find my CV at :

http://www.howell1964.freeserve.co.uk/mycv.htm

http://www.howell1964.freeserve.co.uk/MySkillSet.htm

Personally my greatest concern is the number of employers and their short
duration.
I'm sure people assume the worst, and assume this is because I don't stick
around long.

Well, I have a good explanation for all departures and interviewers accept
them.
(generally if someone is a flibbertigibbet and lying it then it does show
through).

The frustrating thing about this career is getting a solid foothold.
Allbite were run by an intolerable crook (his co-director packed it in after
one year, I endured it for two!). Arcam seemed a lovely stable company,
right up to the day it sacked an eight of its workforce (so no complaints
against me personally!). Prior Scientific have very little skills in the way
of how to plan and run a software project so that if the main engineer
leaves then his successor finish the project.

I expect you will give me an opinion unclouded by a desire not to be
hurtful - this is a good thing because that's exactly the opinion employers
/ agents form. I don't think they have the spine to say "no, you look hard
to sell because of this that and the other" which might upset some people.

Ho hum, life does throw things at people. No use complaining, nobody cares,
just have to deal with it.

Do have a browse around my site, might give you an idea of my geeky
interests.
The computer-in-FPGA is the most complicated project so far, and the most
fun!

http://www.howell1964.freeserve.co.uk/logic/polymorph_project.htm


Cheers, K.
 
John Fields wrote:

Guy Macon wrote:

What kind of god would [snip]

A god that hates you?
That would explain a lot... :)

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

Jim Thompson wrote:

Ah! Guy Macon... he's on my list ;-)
I can't help wondering why. :(
 
On Thu, 20 Jan 2005 16:00:04 -0700, Jim Thompson
<thegreatone@example.com> wrote:


Ah! Guy Macon... he's on my list ;-)

As for you others, I usually kill on more explicit subject definition
with expire after "x days" of inactivity... otherwise the killfile
grows exponentially. So, currently, I have less than 100 listings,
about 30 of which are leftist/EuroPeon authors with permanent status.

...Jim Thompson
After 10 years online I have yet to bother with any sort of
killfile...I may be on a list or three, but nobody is on my list. Yet?
:)

Tom
 
Inasmuch as I'm typing this on a Tadpole SPARCle running Solaris, I
have heard of Unix (Linux is Unix). And PXI/CompactPCI is the PCI bus
put on a different and more benchworthy form factor. Despite using the
same bus, chipsets and firmware, the prices are pretty harsh. VXI is
the old VMEbus and the prices are really out there. Sorry.

Putting Linux on the PC, or using a Mac, SPARC or SGI doesn't change
the fact these are desktop computers and not test instruments. PC
test-as opposed as PC _control_ of test, which is what AP and Agilent
and Tek have done for decades-is awkward, electrically iffy, and a pain
in the ass and it sucks. It's as simple as that.

Be that as it may, I would love to have a Collins 95S-1.....although
not really an audio box, it would be a fun toy. Would be more fun if it
had a front panel, though.
 
On Thu, 20 Jan 2005 08:09:17 -0800, John Larkin wrote:

On Thu, 20 Jan 2005 00:02:40 GMT, Rich The Philosophizer
rtp@example.net> wrote:



Do you choose cowardice and death? Judgement? Rigidity? Order? Structure?
Death?

In this ng, I choose electronics. Really, you should try it sometime.
It might give your mind something real and useful to do.
Yeah, thanks. I gave John Woodgate a treatise, and I believe I've done
what I can as far as "spreading the word", so I'll quit harping, and if
you want to know more, just ask.

Thanks,
Rich
 
On Thu, 20 Jan 2005 23:40:15 GMT, Tom MacIntyre
<tom__macintyre@hotmail.com> wrote:

On Thu, 20 Jan 2005 16:31:48 -0700, Jim Thompson
thegreatone@example.com> wrote:

On Thu, 20 Jan 2005 23:21:24 GMT, Tom MacIntyre
tom__macintyre@hotmail.com> wrote:

On Thu, 20 Jan 2005 16:00:04 -0700, Jim Thompson
thegreatone@example.com> wrote:


Ah! Guy Macon... he's on my list ;-)

As for you others, I usually kill on more explicit subject definition
with expire after "x days" of inactivity... otherwise the killfile
grows exponentially. So, currently, I have less than 100 listings,
about 30 of which are leftist/EuroPeon authors with permanent status.

...Jim Thompson

After 10 years online I have yet to bother with any sort of
killfile...I may be on a list or three, but nobody is on my list. Yet?
:)

Tom

Most of my list is actually just topics for which I have absolutely no
interest*, so I just put the subject in my list with a
delete-from-list after 15 days of inactivity, so it's self-cleaning.

* Like "555", "LED", etc ;-)

...Jim Thompson

I'd suspect that "wine" will never show up there? :)

Tom
Actually, I can't recall of wine coming up as a _subject_line_, just
some bantering between John Larkin and myself about the wine we were
currently sipping, what we had at lunch, etc.

But, Hey! It's quarter to five... think I'll go pour myself a glass
;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
 
On Thu, 20 Jan 2005 16:49:49 +0000, Kryten wrote:

"John Larkin" <jjSNIPlarkin@highTHISlandPLEASEtechnology.XXX> wrote in
message news:8qlvu0db03p0njtk1im372pi0m4kivfigp@4ax.com...
On Thu, 20 Jan 2005 00:02:40 GMT, Rich The Phuloshitter
rtp@example.net> wrote:
snip irrelevant rantings

Please don't respond to Rich.

He's a pathetically lonely guy who craves attention, even if it is ridicule.

I've kill filed his bullshit, but if you reply to him I just get more
irrelevant posts.


Rich: I've been listening to God and He says you're an annoying crossposting
mental case.
How can you tell it's God? Are you sure it's not Ahriman telling you these
things? Notwithstanding I'm pretty much a "mental case" by most criteria,
and I've been annoying since very soon after I was born.

Crossposting, eh - once or twice, but hey, whatever you want to obsess on,
be my guest! ;-)

Thanks,
Rich
 

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