Electrical Engineering

Anindo Ghosh

1:25 AM

grEEtz pEEplz

angelatlarge

@AnindoGhosh Anindo!

@AnindoGhosh Can I pick your brain on something?

Anindo Ghosh

Heya @angela :-) Sure, please do.

angelatlarge

OK, still working out those TLC LED drivers. I think I know what the problem might be, but I am not what's the best way to solve it: I can think of three ways, none of them seem great. OK...

These LED drivers need an external clock. At the end of 256 or 4096 (or whatever) cycles, you need to twiddle the BLANK line, and then the cycle starts again. Does this make sense so far?

Anindo Ghosh

@angelatlarge Please share the problem statement before the 3 solution hypotheses?

angelatlarge

@AnindoGhosh +1

Anindo Ghosh

1:30 AM

brb 2 mins, still waking up.

angelatlarge

@AnindoGhosh OK

Anindo Ghosh

1:43 AM

@angelatlarge back

@angelatlarge Yes, I get it so far.

angelatlarge

@AnindoGhosh Cool. Anyway, did that part about the clock and BLANK make sense?

Anindo Ghosh

^^

angelatlarge

@AnindoGhosh Ok, now you load the data serially (SPI) and after sending in the right number of bits you LATCH it. Except that the datasheet says that you want to LATCH at the end of the greyscale cycle, i.e. when you would BLANK the leds to reset the cycle. Makes sense?

Anindo Ghosh

@angelatlarge Yes. Pulling up datasheet now.

angelatlarge

www.ti.com/product/tlc5940

page 12

Anindo Ghosh

1:47 AM

OK go on

angelatlarge

OK, so I need to clock in the data during the greyscale cycle, because of timing issues.

So, here's the question: how to implement the greyscale clock + BLANK + LATCH at the end of the greyscale cycle on a system where clocks are precious.

Anindo Ghosh

@angelatlarge Remind me, are you serially cascading the TLCs? or are they separate parallel devices?

angelatlarge

Oh, and LATCH while it should be at the end of a greyscale cycle must only happen after all the data is clocked in.

Now it is serial.

There will be 24 of them :) Currently only 3 :(

Anindo Ghosh

@angelatlarge Remind me also whether you looked at the Arduino TLC5940 library source. I haven't but I've used that library successfully in the past.

angelatlarge

@AnindoGhosh I have not. I suspect theirs is not fast enough for me. I have some special needs.

Anindo Ghosh

1:53 AM

@angelatlarge (a) They may be slow but they may be addressing your current problem. (b) Not looking at existing code sounds odd to me.

angelatlarge

Ok, point taken. Can we assume for the moment that it will not fill my needs?

Anindo Ghosh

@angelatlarge Also see this for some TLC5940 tips and gotchas: effluviaofascatteredmind.blogspot.in/2012/05/…

angelatlarge

And I can address my current problem slowly. The question is how to address it fast

So the way I did clocking before is using the CLKO output of ATmega + a single PWM timer for the BLANK line. But this doesn't take care of proper LATCHing (though it worked fine in parallel). I am thinking about a pure hardware solution: flip-flops + counter and stuff like that + CLKO line for greyscale + BLANK + LATCHing. Is that crazy?

Anindo Ghosh

@angelatlarge I did not propose that the library itself would fulfill your needs. I proposed merely that they may have addressed some aspects of your needs :-)

angelatlarge

@AnindoGhosh I've read that before

Anindo Ghosh

1:57 AM

@angelatlarge I was going to say use a decoder, say a 3-to-8, or better yet, a SIPO like the TPIC6595, to deal with your latch/blank line shortfall: Basically any SIPO with latching output.

angelatlarge

@AnindoGhosh What is SIPO?

Anindo Ghosh

@angelatlarge Serial In Parallel Out

angelatlarge

@AnindoGhosh Hmm... it's not that I have a line shortfall, it's that I don't want to do greyscale clock in the processor: will take too much time. Alternatively I could use two timers, but that's one timer too many. You see?

Anindo Ghosh

@angelatlarge Here's one way I'm looking at the problem: Your data is a fast-clocked signal. Set that aside for the moment. Your blank / latch are essentially a separate set of slow-clocked digital signals (don't think of them as serial data with any standard serial mechanism such as SPI), if you consider them in isolation, can you work out separate triggering conditions for them?

angelatlarge

@AnindoGhosh No, that's exactly right, and that's how I am thinking of it. Just the question of how to take care of the second while eating hardly any processor time.

Anindo Ghosh

2:01 AM

@angelatlarge What I am saying is, those other (non-Serial-data) lines do not need a timer of their own, they trigger relatively occasionally when some other condition, i.e. end-of-192-bits-of-data-through-serial, is met.

angelatlarge

@AnindoGhosh Ah, no. The BLANK line needs to be twiddled every time the clock max is searched, regardless of datain and latch.

Anindo Ghosh

@angelatlarge searched?

angelatlarge

@AnindoGhosh If there is data to be latched, that's when the latching happens, but that you are addressesing

searched -> reached

Anindo Ghosh

@angelatlarge OK, so I would do BLANK on TCO overflow if my number-of-bits is known. Each timer has two counters, first you've already used, right? Second counter / overflow can trigger the blank twiddle, perhaps?

angelatlarge

@AnindoGhosh Yeah, that's the problem. I need those other timers for other stuff, plus that would be using real clock cycles for BLANK, which I'd like to avoid.

OK, I need to run.

@AnindoGhosh But I'll bug you some more about it another time

Anindo Ghosh

2:05 AM

@angelatlarge ... and again, I'd be curious to at least examine the existing libraries (and I note that there are some libraries out there for TLC5940 independent of the Arduino family).

angelatlarge

@AnindoGhosh Or actually ask a question

@AnindoGhosh Yeah, I'll take a look. You are my sock overlord.

@AnindoGhosh I am a skeptical sock pupper, however :)

Anindo Ghosh

@angelatlarge The TLC5940 is such an overused part, that people have done pretty much anything there is to be done, with them, on every conceivable MCU platform.

angelatlarge

@AnindoGhosh Really? I didn't realize it was so popular.

Anindo Ghosh

@angelatlarge You're also the first pupper I'm getting introduced to.

angelatlarge

A Schotty pupper

OK @jippie says: /me=out (or something like that)

Cheers!

Anindo Ghosh

2:07 AM

@angelatlarge Probably the second or third most used serially controlled chip I can think of, by hobbyists.

The Photon

3:52 AM

Can I put individual users on ignore?

The guy asking all the digital logic homework questions needs to just read his damn textbook!

Anindo Ghosh

5:16 AM

@ThePhoton Yes

Anindo Ghosh

5:50 AM

Anyone here a math LaTex expert?

rawbrawb

@AnindoGhosh I fumble around, what do you want? I might be able to help.

and it's LaTex, latex is what you wear!

Anindo Ghosh

I would like something that expresses Lim(V --> Vcc), standard asymptotic expression

@rawbrawb Oops, fixed. Never wore the stuff, though.

Even better, something that says time tends to infinity as the limit tends as mentioned above.

rawbrawb

\$ Lim_{V->Vcc} \$ would sort of work. I should really test it before making that claim though. ;)

especially after a long day of dealing with "issues"

Anindo Ghosh

By the way, @rawbrawb, I loved your analog - digital answer:

9

A: What is the use of analog circuits today?

There are lots of examples that people will use that point out the "exception" to the rule where you can't use digital design approaches for signals, like: dealing with RF or very high frequency signals, most digital motherboards in computers have a very "analog" design cycle. conversion from t...

rawbrawb

@AnindoGhosh thanks, hope I didn't come across as too bitter. ;)

damn bit-weenies!

oops, shouldn't have said that!

Anindo Ghosh

5:54 AM

@rawbrawb I think it was very on-the-ground realistic.

rawbrawb

and what was up with Kaz saying " once it's abstract it can be anything" WTF?

I found this ... \lim_{x \to \infty}

Anindo Ghosh

Just shared your answer on G+. Am I in your circles?

rawbrawb

@AnindoGhosh don't know, rarely use that, although I probably should.

Anindo Ghosh

@rawbrawb OK, I have no idea how to add that math into my answer, so I give up. If you (or someone) would want to add that into my answer, it would be neat.

0

A: 4 or 5 Time Constants to reach practical potential?

The correct answer to this question would have to be: Neither, the set point is insufficiently specified. To elaborate: Let us say the component in question is a capacitor, to be charged / discharged. As this charging / discharging process approaches limit asymptotically, clearly there is no...

rawbrawb

@AnindoGhosh excellent -> tented fingers, I'll get to it!

Anindo Ghosh

6:01 AM

@rawbrawb You would have received a notification from G+ that you were added to my lists, adding me from that notification should be possible.

@rawbrawb While you are at it, you are probably much better qualified than me to improve my answer, I've captured the essence without expressing the basic math. I wish this were MS Word, where I used to be quite adept at mathematical notation.

rawbrawb

@AnindoGhosh actually, I'm too toasted right now to be of use. maybe tomorrow for teh edit. I'll check G+ right now. Are you on Twitter?

Anindo Ghosh

@rawbrawb Yes, I am on twitter, and yes, tomorrow would be fine - I only asked because, from a long-term value point-of-view, the answer would merit from a gentle touch of the relevant math, understandable at a lay-person level of course.

rawbrawb

@AnindoGhosh I hear you, started to get into LaTex as my primary documentation source as I thought that it would be handy to have stuff ready for publication. BUt most technical journals don't accept LaTex only Word. WTF? and Humanities journals accept LaTex.

Anindo Ghosh

@anindo, Mumbai, India

Pro photographer specializing in low-light and location photography

154 tweets, 105 followers, following 118 users

@rawbrawb Yes, the patent office in India is similar, no LaTex, only PDF or MSWord.

rawbrawb

@AnindoGhosh BTW one of my friends (he's on G+ and Twitter) is a camera junkie. and a good photographer, he has something like 400 - 500 cameras of all sorts from field cameras to leicas to brownings.

Stacey Anne

6:16 AM

Hi guys

rawbrawb

@StaceyAnne grEEts

Stacey Anne

@AnindoGhosh, @rawbrawb, know any verilog?

Or anyone else in here for that matter

Anindo Ghosh

@rawbrawb Than makes him a collector or curator, does not necessarily follow that he is a photographer ;-) Much like museum curators who are great art historians, but that does not imply they are artists. Just being pedantic, not casting aspersions on your friend's abilities and talents :-D

rawbrawb

@StaceyAnne too rusty sorry.

Anindo Ghosh

@StaceyAnne Not me, sorry. Notice that Verilog / VHDL discussions are the only times I stay absolutely quiet ;-)

By the way, @jippie's starred comment makes me laugh every time I re-read it:

9 hours ago, by jippie

@DavidKessner you're just jealous that your microcontroller doesn't come with pin headers

Stacey Anne

6:19 AM

tis fine, I'll hang around until thephoton arrives and bug him

rawbrawb

@AnindoGhosh but he is ALSO a good shooter. I've seen his work.

@StaceyAnne it's appraoching 12:00 midnight his time. (i'm in same time zone)

@AnindoGhosh yes!

Anindo Ghosh

@rawbrawb Like I said, not denying that at all. :-)

rawbrawb

@AnindoGhosh and that is notable in that it's an true exception. Oh most voluble one.

bazinga!

anyways, it's time I get to snores ville. ciao all!

Anindo Ghosh

@rawbrawb I don't lack awareness of some of my failings, such as this one. :-)

@rawbrawb Sleep well, don't overwork, take a holiday.

abdullah kahraman

6:56 AM

Hi!

@AnindoGhosh Nice job on Arduino.SE

Anindo Ghosh

@abdullahkahraman Thanks (I think)... I don't think I've done anything deserving praise. @AshRj and @Manishearth deserve kudos for driving the proposal through.

abdullah kahraman

7:11 AM

Kudos to @AshRj and @Manishearth !

Rick_2047

7:24 AM

hey all, i have a question. I am using an lm358 which is a dual op amp, but I am using only one of them. what should I do with the pins of the other one?

PeterJ

Hi @Rick_2047 take a look at analog.com/static/imported-files/rarely_asked_questions/…

Rick_2047

i am F*d

the pcb is already made and there is a 6 o'clock deadline

would have to use some wires now

@PeterJ I have a 2.5V supply generated somewhere on the board and the rails are 10V. should I connect a wire of that voltage there?

Anindo Ghosh

@Rick_2047 Make them into a voltage follower hanging off a voltage divider, anywhere around Vcc/2. Else problems.

Rick_2047

@AnindoGhosh I am retrofitting a PCB here,

I am going to use this configuration

Anindo Ghosh

@Rick_2047 Yes, 2.5 Volts would be ok for the voltage follower input.

Rick_2047

7:33 AM

cool

chat room saves my life again

Anindo Ghosh

@Rick_2047 been there, burnt that, so to speak. Overheated a quad op-amp once due to one floating pin on an unused amp, was hell to identify the problem, because it was intermittent. Randomly the gain of the device would change.

Rick_2047

@AnindoGhosh and that is why this chatroom is awesome

@PeterJ you are awesome

Anindo Ghosh

@Rick_2047 Because it's full of pyromaniacs. :-)

Manishearth

@abdullahkahraman /cc @AnindoGhosh thanks :)

Anindo Ghosh

@Manishearth :-)

Rick_2047

8:26 AM

@AnindoGhosh do you have your own personal oscilloscope?

Anindo Ghosh

@Rick_2047 Yes

Rick_2047

@AnindoGhosh can you give details, specs, prices, where you bought it or something like that

Anindo Ghosh

Owon SDS7102. Quite nice, and at a decent price. Rs.27,619, bought it from the India distributor, MetroQ in Lajpat Rai Market, Delhi. Service and warranty support are fantastic: I once blew out the input stage by doing something silly, and they replaced it under warranty without any questions asked or any fees. They also couriered the unit to their dealer in Mumbai, so I just had to pick it up from there and pay them some Rs.150 shipping cost.

Rick_2047

hmm... nice

Anindo Ghosh

I've recently sent it in for recalibration as it was off by about 1.5% or so, though MetroQ's owner did grumble that 1.5% isn't even outside the specification, he took it in and sent it to their India factory (Gurgaon, I think) for a full lab calibration, again at no charge.

Rick_2047

8:32 AM

what is the bandwidth?

Anindo Ghosh

@Rick_2047 The price from the dealer in Mumbai was Rs. 34,000.

@Rick_2047 100 MHz. There's a review on YouTube:

►

PeterJ

10:31 AM

@AnindoGhosh, looks cool, I've got an Agilent DSO3202A (now discontinued) which has fairly similar specs but being an older unit the 4 kpts memory depth isn't so great for capturing serial data streams. The free included software doesn't work under Windows 7 either which is a bit slack when it's still listed as supported until Dec 2015.

Rick_2047

@PeterJ is this a PC based DSO?

PeterJ

@Rick_2047, it's a standalone one somewhat similar to the one Anindo posted just an older model. So I really only use the software occasionally if I want to capture waveforms to a PC which isn't that often so I just use XP under VMWare. The product page is here if you wanted to take a look at the exact model home.agilent.com/en/pd-580333-pn-DSO3202A/…

Rick_2047

is it a driver problem or the software does not install

because if its a software problemyou can always writeup a script to capture the data

oscilloscopes are perhaps the most expensive instrument everyone has

PeterJ

10:46 AM

Been a while since I've looked at it but believe if was a driver problem, I think from memory because it uses an unsigned driver that won't work on x64 systems. I saw a complaint on their forums and an Agilent staff member said it wouldn't work and they weren't planning an update. He got a bit of a flame from the OP it's be the last bit of Agilent gear he'd buy lol.

But anyway I mainly use it standalone, probably only use the PC software a few times a year so the minute or so to boot XP under VMWare isn't a big deal.

Anindo Ghosh

I guess when a business has held leadership position for too long, they begin to listen to customers less.

The Owon software works fine on Win7x64.

PeterJ

Yeah it's a bit disappointing for Agilent when "cheap" has never really been their selling point - you'd think they'd make a better point of long term support.

Stacey Anne

11:23 AM

is there a stackoverflow site or chatroom where I can ask about which laptop I should buy next?

Dean

11:33 AM

@StaceyAnne Macbook pro :D

Stacey Anne

@Dean, eh, I need to run Xilinx tools

Dean

@StaceyAnne so run windows on it :D

PeterJ

Not really sure if any SE main sites encourage shopping questions, I've never been there but I guess the Superuser chat root might be OK. The high-end CPU / RAM requirements the Xilinx tools need might be the sort of thing the people who hang out there would have ideas about.

Stacey Anne

11:49 AM

My biggest problem is with cooling, Ideally I need a quad core i7 with 16 gb of ram in a laptop that somehow stays cool even when I excercise it fully

Rick_2047

@StaceyAnne in my experience you can never get proper cooling for laptops

Stacey Anne

@Rick_2047, yup, that's my experience too. I'm really struggling to get my existing laptop to stay cool when synthesizing code.

Rick_2047

true @StaceyAnne, it is better to have like a desktop

isn't there a cloud based way to use it?

PeterJ

Yeah have the same problem here during summer sometimes. Not sure if any of those 'cooling pad' type things that have fans underneath work OK or not, never tried one because I use a desktop for most things.

Stacey Anne

@Rick_2047, that's the problem, I'm travelling a lot at the moment. Have considered cloud, but what I need is $250-$500/month

Rick_2047

11:55 AM

thats expensive

but maybe you can buy a beefy desktop and setup a service there

Stacey Anne

I was thinking of buying a beefy desktop and leaving it at my parents place

the thing is, they're in South Africa where the ping times in and out of the continent are abysmal

@PeterJ, I'm using a cooling pad all the time, my pc sounds like a server farm, but it only really helps by 2-3C

PeterJ

@StaceyAnne while normally Australia and New Zealand have some healthy rivalry occasionally a Kiwi comes up with a good idea, maybe you should check out this project... asciimation.co.nz/beer

PeterJ

1:38 PM

I'm not sure if this question was better before or after I inlined the images

-1

Q: Problem with delay before LED turns on

Series LED: How do you make a LED circuit in series where the next LED will turn on, with equal brightness after a certain time delay? For example, when I turn on the power, the red lights will turn on and after 10 seconds, the orange ones will light and 10 seconds after the orange LED lights...

led

Kortuk

2:08 PM

@PeterJ the inline'ed version has the advantage of giving olin an aneurysm.

@PeterJ if I meet someone and can not tell which accent it is I always say kiwi. If they are nice, then they were a kiwi. If they get really pissed, they are an auzzie. But Kiwis are nice no matter what I call them, so I try to make it a more enjoyable experience for them

;)

PeterJ

@Kortuk, lol, how well they take a stirring from Aussies I think depends on the results of the latest cricket / rugby matches.

jippie

3:12 PM

good morning

PeterJ

Hi @jippie! Really early morning so I'm about to head off.

jippie

17:14 is not particularly early

PeterJ

01:15 is

Beer-o-clock for you though, so I'm handing over the shift

user61389

Does anyone know how it's going on the Arduino private beta?

user61389

Perhaps a little too early to ask though

The Photon

3:20 PM

@StaceyAnne Online now, but headed for the lab pretty soon.

Kortuk

3:34 PM

@PeterJ ha.

user61389

4:52 PM

@Kortuk what was our policy on chip-specific tags again? electronics.stackexchange.com/q/61592/17592

Anindo Ghosh

5:25 PM

@camil Are you not a beta invitee to Arduino?

user61389

@AnindoGhosh I didn't commit, I'm not an Arduino user. Could I get an invitation without having to commit?

Anindo Ghosh

Yes, you can be invited through "invite an expert". Would you like me to?

user61389

@AnindoGhosh Yes please! :) if you don't care about lying to the system that I'm an expert ;) my e-mail is *********************

Anindo Ghosh

Oh, wait it needs the invitees email address... Is it on your profile?

user61389

@AnindoGhosh it's on the end of my last line :)

user61389

5:32 PM

@AnindoGhosh Cool, thanks! :)

Anindo Ghosh

Yeah, saw it after I hit send :-)

user61389

"Anindo Ghosh told us you're just the right kind of expert the Arduino Stack Exchange Q&A site needs." Well, I'm flattered :P

Anindo Ghosh

@Camil You are an expert... In something. It doesn't say that you must be an Arduino expert, I checked before sending the invite.

user61389

@AnindoGhosh oh, you!

Kortuk

6:51 PM

ha

@CamilStaps I dont have an issue with them, single use tags go away on their own after 6 months, so it probably will. It probably needs a tag for the fact it is heat related failure analysis.

user61389

@Kortuk okay, won't make an issue of it then

Kortuk

@CamilStaps I dont. I did not even care if people tagged the book that things came from, as long as it specifically describes the problem it will go away on its own if it is a single use tag.

user61389

7:04 PM

@Kortuk thanks for editing out my e-mail address, by the way :)

Kortuk

@CamilStaps NO worries, did not want to presume to know that you would want that, but was pretty sure you would.

jippie

if I have a multiplexed by an ATtiny2313 (which I succesfully unbricked) 7 segment LED display, and I want to make it brighter, what are my options?

Kortuk

Turn on less sections :)

jippie

it does make a difference, true, ...

user61389

@jippie In theory, longer delays before switching to another LED (might need to speed it up), but how much that will change...

jippie

7:07 PM

@CamilStaps tried that, but even when I drop from 50kHz to 50Hz, the difference isn't too impressive

Kortuk

@jippie If you have dead sections where you are deciding who to turn on next making sure the last section stays off for that time would help.

jippie

.

user61389

@jippie perhaps capacitors then? :) or a higher voltage?

jippie

both anode and cathode are driven by the avr

Kortuk

@jippie if there is any point where no segments are on you might want to optimize your code to be a little slower but when it switches run the code to go between to segments as just quick IO sections.

user61389

7:11 PM

@jippie use a PIC instead! ;) i.e. I don't know anything to help anymore

jippie

@CamilStaps maybe I shouldn't buy cheap chinese junk

user61389

@jippie :)

The Photon

Where is the FedEx truck?

jippie

The Photon

@jippie I suspect there are USPS trucks inside those UPS trucks.

jippie

7:15 PM

@ThePhoton :)

is the stack down?

user61389

@jippie I had trouble a minute ago too, now everything's fine again here...

Kortuk

@CamilStaps the concept is the same.

user61389

@Kortuk I wasn't entirely serious ;)

Kortuk

@CamilStaps :)

jippie

I ran a check for amount of ACR questions vs PIC questions. Obviously PIC gives people more questions => more stress => less happy => shorter lives.

user61389

7:24 PM

@jippie I'm not sure if that's statistically correct :)

jippie

Hi @AndrejaKo, just click the right buttons

AndrejaKo

@jippie Can't log in with Firefox, so I had to switch to Internet Explorer...

jippie

?

@AndrejaKo strange, I have no problems (yet) with FF

AndrejaKo

I've had problems several times, but only with chat, main sites work fine..

Kortuk

@jippie or it has more support. :)

AndrejaKo

7:31 PM

Sometimes I can log in and sometimes I can't, so it's a bit strange.

jippie

I followed the link in your comment @AndrejaKo and I downloaded a patched version. That patched version, however not really stable, did fix the problem.

github.com/sylvandb/ArduinoISP/blob/…

user61389

@AndrejaKo I had some issues because I disabled sending referer headers. Did you ever mess with the about:config page?

Kortuk

@AndrejaKo open this page with firefox. chat.stackexchange.com/help

@AndrejaKo it should tell you the root cause.

AndrejaKo

No, but when I tried to log in via stackexchange.com/users/chat-login , I did get the missing referers error.

user61389

@AndrejaKo perhaps an add-on that sets a different referrer?

jippie

7:33 PM

Test 5: Communication with stackauth.com – failed

KronoS

Anyone here willing to answer a few beginner VHDL questions?

AndrejaKo

Probably. I'll see about that.

The Photon

@KronoS General digital design I can do. VHDL syntax, not so much.

KronoS

:/ I think it's a VHDL syntax issue

I'm curious how things connect up in that language

AndrejaKo

@jippie That's good to hear. It would be nice to make a stable patch that would allow SPI frequency to be changed.

The Photon

7:35 PM

@KronoS like "implementation" and "architecture"? Exactly the kind of stuff I don't know.

KronoS

@ThePhoton lol... actually component and entity

The Photon

@KronoS Those sound even worse. At least "implementation" and "architecture" have some meaning to me.

KronoS

oh and architechture as well lol

jippie

@AndrejaKo if you move your comment to an answer (you can include my link), I'll accept it with a comment that it works most of the time but sometimes fails (and I just retry and it works).

KronoS

@ThePhoton anyways thanks for your willingness :)

jippie

7:36 PM

@AndrejaKo I'll delete my chat invite

AndrejaKo

@jippie OK, I'll try to make an answer that makes sense...

@jippie Also Im not sure how ethical it would be for me to post an answer now... There are already few answers which explain the issue quite well and I don't see how at this point I could make a better answer...

jippie

your link solved the issue, the others only explain the cause

AndrejaKo

OK then.

jippie

otherwise I will write the answer myself :o)

Anindo Ghosh

@Kortuk You here?

@jippie which question is being discussed?

AndrejaKo

7:44 PM

@jippie I'm writing! :)

jippie

@AnindoGhosh a low hanging fruit question that you missed

Anindo Ghosh

@jippie Oh, that's OK, I was out doing real work today, but still, which question?

jippie

the controller unbricking

AndrejaKo

Here's the link electronics.stackexchange.com/q/64978/1240

Anindo Ghosh

@jippie Ahhh solved? I'm glad.

jippie

7:47 PM

of course

Anindo Ghosh

@jippie So it was what @AndrejaKo and @angelatlarge surmised - bring SPI clock speed down and you're sorted.

Gahhh, I wish chat would allow people with low rep to participate, at least in a question-linked chat room.

jippie

@AnindoGhosh yups

@AnindoGhosh you need 20 rep, don't you? What question?

KronoS

@ThePhoton In case you're ever interested this is a good resource for the VHDL language.

2

jippie

8:05 PM

@AnindoGhosh you actually need to be invited to Arduino?

user61389

As long as it's in private beta

KronoS

I don't think you can even be invited... it's only those that followed

user61389

@KronoS Those who are in, can invite others. There's a form in the sidebar.

KronoS

@CamilStaps ah didn't know that

Anindo Ghosh

@jippie do you need an invite too?

jippie

8:27 PM

no, I'm busy enough as I am. Thnx anyway

@AnindoGhosh I'm afraid for all the Fritzing-level circuit diagrams and I don't have the patience like you do.

I'll check in every now and then though. Maybe the Arduino stack will convince me to stay in due time

Anindo Ghosh

@jippie OK

Kortuk

@AnindoGhosh I am now, whats up.

jippie

But you make me curious, can't I just commit?

ah I could until yesterday

but there is a 7 times starred invite in EE chat.

anyways, dishes are done

time for bed

/me is out

Anindo Ghosh

@Kortuk I tried flagging a message, it gave an error repeatedly - the question is this one, and the comment is the one with the phone numbers.

Kortuk

@AnindoGhosh you might want to meta the errors, I will clean it up.

@AnindoGhosh Thanks for the heads up, sorry I was not here.

Anindo Ghosh

8:35 PM

@Kortuk Thanks. I couldn't find a reference to link to him/her about how contact info is not allowed. Any ideas?

@Kortuk Also, I wish 10-rep folks could come and chat. That person, I am sure I could have provided him excellent insight into sourcing obsolete parts.

Kortuk

@AnindoGhosh I can help with that. Let me make you a room owner, I think you can explicitly add them.

Dean

@AnindoGhosh Do you know theres a bug when ordering samples from TI?

Anindo Ghosh

@Kortuk I am not sure that works, I was under the impression they can be invited but cannot type.

Feeds

Kortuk has added Anindo Ghosh to the list of this room's owners.

Anindo Ghosh

@Dean What kind of bug please?

@Kortuk OK so how do I invite him here?

jippie

8:38 PM

@AnindoGhosh I've never seen a button for that @Kortuk

Dean

well with a bit ok poking around on the site i've been able to order some microcontrollers twice.

Anindo Ghosh

@jippie Oh, just create a new room, you'll see the button.

@Dean go on.

Kortuk

@AnindoGhosh I think you can add their access.

Anindo Ghosh

@Kortuk OK I'll work on it.

Thanks.

Kortuk

@AnindoGhosh one second. Let me put a link in to where you do it.

jippie

8:40 PM

oh i see it now

the red buttons :)

Kortuk

chat.stackexchange.com/rooms/info/15/…

Dean

Well i Need more msp430g2553, So i browsed through their website to find them then clicked on the add samples to basket thing then once logged in to their samples system I again searched for the product(msp430g2553) and it allowed me to again add it to the cart.

it will be interesting to see if they actually deliver 4.

jippie

amyways, me was on the way out.

Kortuk

You should be able to add them to explicit read access, the hard part is finding a link to their account.

Dean

@AnindoGhosh Take a look at what I actually ordered.

Anindo Ghosh

8:42 PM

@Dean Oh, yes they will. We once had a MoQ problem with a part, and the TI rep himself promptly added the part to the samples basket multiple times and said "There you go!"

@Kortuk Well, I guess I'll add write permissions for that person if I can locate his link, and if he takes me up on the chat invitation, then I'll try to help him.

Dean

@AnindoGhosh Fair enough

Anindo Ghosh

It was tempting though - a thousand of those ICs = easily a $1000 or greater profit for me, tax free. :-)

Kortuk

@AnindoGhosh Sorry, I believe that is how you do it, that is why I think there should be an "invite to chat" method for high rep users to new users.

@AnindoGhosh haha. Nice.

Anindo Ghosh

@Kortuk My moral code and my dollar code are fighting it out, and my ulcers are in the audience applauding.

4

Kortuk

@AnindoGhosh haha. That statement is awesome.

Anindo Ghosh

8:47 PM

BTW you did note what I did there, on that question, right? I happen to have access to those ICs, I had a few samples at home, he posted the question, I took a photo and posted in a comment, it startled the heck out of the guy: He had recently written a comment "There is no stock anywhere in the world, grey market or OEM/CM".

Kortuk

@AnindoGhosh haha. Well done.

Anindo Ghosh

@Dean No matter what your purpose, TI has way better options for both the dual and the quad op-amp you selected... Even in DIP, if that was your concern. I think you wasted your sampling slots a bit.

@Dean Also another tip - never put anything into your samples basket that is back-ordered. Those cases get reviewed, and someone might then start asking why you want what you want etc.

Kortuk

@AnindoGhosh interesting.

The Photon

9:02 PM

@KronoS Thanks, I'll check it out.

Dean

@AnindoGhosh meh op-amps are always good for filling up the parts bin.

@AnindoGhosh I'll note that next time.

Anindo Ghosh

@Dean op amps yes, but at least get the RRIO-SS ones, and the low-drift ones. TI has some amazing hardware in that space. A non-RRIO op-amp is so 1970s.

@Dean Also, if you are enthusiastic about learning op-amps, I would have expected at least one current-feedback op-amp in that basket. Voltage op amps are routine stuff.

angelatlarge

Hallo all troll-bashers!

Anindo Ghosh

9:45 PM

@angelatlarge What about the rest of us? No hello?

angelatlarge

@AnindoGhosh :) Hi @AnindoGhosh. What you don't flag?

Anindo Ghosh

@angelatlarge Unflaggingly - but not trolls.

angelatlarge

@AnindoGhosh You don't play flag with trolls?

Anindo Ghosh

@angelatlarge I don't play with trolls.

Kortuk

10:02 PM

@angelatlarge Not everyone enjoys doing it, I signed up before the troll existed, @W5VO signed up knowing full well :)

angelatlarge

@Kortuk I wasn't trying to make a statement about enjoyment. :)

Hi @Kortuk :)

Kortuk

@angelatlarge I just mean the opposite, some people really hate it and do their best to avoid the whole fiasco.

:)

angelatlarge

@Kortuk Sure

angelatlarge

11:21 PM

Anyone still around?

The Photon

@angelatlarge hi

angelatlarge

@ThePhoton @ThePhoton hello!

Kortuk

@angelatlarge @angelatlarge Hi.

The Photon

@angelatlarge @angelatlarge hello to you too

angelatlarge

You guys use logic analyzers?

The Photon

11:24 PM

@angelatlarge Have done,

angelatlarge

@ThePhoton But probably professional level, yes?

The Photon

@angelatlarge Mmmm, really just for simple stuff.

angelatlarge

@ThePhoton Oh, sorry, I meant as far as the equipment

@ThePhoton I am using a bus pirate right now, and it's not quite doing what I need it to.

Kortuk

@angelatlarge :(

Driving home, later guys

angelatlarge

@Kortuk Have fun!

The Photon

11:26 PM

@angelatlarge Yeah, but my former boss was willing to fork out for fancy test equipment, but then wouldn't want to spend money on the little accessories. So we had a $6-figure logic analyzer, but no probes to connect it to any circuit boards...

angelatlarge

@ThePhoton Brilliant!

The Photon

Capital and expense budgets were way out of whack.

angelatlarge

@ThePhoton Actually, I am in the same boat sort of: came across a trashed $2K logic analyzer at school, but no probes, and no job at the moment :)

The Photon

@angelatlarge Anyway, what's a bus pirate?

angelatlarge

dangerousprototypes.com/docs/Bus_Pirate

Kortuk

11:29 PM

@ThePhoton dangerousprototypes.com/docs/Bus_Pirate

I @'ed him :0

Later

The Photon

@Kortuk L8r

angelatlarge

@Kortuk No typing while driving!

@ThePhoton I don't even know how to describe what Bus Pirate is, since I've only used it as a logic analyzer.

@ThePhoton It gives you 5 channels at 2Mhz over USB.

Anindo Ghosh

@angelatlarge What is the problem you're facing with the pirate?

The Photon

@angelatlarge OK, cool. It looks like basically a controllable interface to a few i/o pins. I'd rather have 20 pins or so rather than 5, but for $30 ....

angelatlarge

@AnindoGhosh Can't set triggers to display events that happened before the trigger. The only way to use triggers (AFAIK) is to start capture when the trigger hits.

@AnindoGhosh i.e. no FIFO queue on events, AFAIK

@ThePhoton Yeah, $30. My dollar code won.

What's "bare metal"? (latest post on ARM Cortex)

@AnindoGhosh Do you use the busPirate as a LA?

Anindo Ghosh

11:36 PM

@angelatlarge I think you're right, there isn't.

@angelatlarge Made my own similar device and yes.

angelatlarge

@AnindoGhosh Can you recommend some other cheap-o LA tool, maybe?

Any experience with this: dangerousprototypes.com/open-logic-sniffer ?

Anindo Ghosh

@angelatlarge No, none.

@angelatlarge One of the high rep people on EE.SE, Toby Jaffey, has released an open source Bus Pirate clone, Bus Ninja I think... It is open source, and might lend to what you are trying to achieve, perhaps with some tweaks.

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Electrical Engineering