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2006-08-29 by katraven1
yay~ success! the motors are in motion. the current set-up is to drive the motors using signed magnitude, with the pwm into the enable. now i can drive both motors individually [:D] now the next step: connecting the IR sensor... [:-?] more reading www.barello.net - those dilberts
2006-08-28 by Dennis Clark
That is true about the glitch, I had a tendency to do a "one wire" approach and just enable the bridge, that enable will eliminate the glitch. When playing with LA I didn't see high currents, I just noted that it was the _same_ current no matter what the motor speed was. I did li
2006-08-28 by Larry Barello
Dennis: Solving the glitch problem was the intended use for the ENABLE line (and coasting). If you are seeing large current draw with LA then your PWM rate is way too slow. That is the big problem with LA, IMO, is that pwm rates of 60-120khz are needed with small, low inductance
2006-08-28 by Dennis Clark
Any H-bridge (usually) can be drived locked antiphase. My biggest problem with locked-antiphase is power up glitch. You have to have the PWM at the center duty cycle or the motors turn. Which means that when you start up and your line is low, your motor takes off full bore until
2006-08-28 by katraven1
wow.. thx for the readings =) after that I've done some more research into this area and some more n00bie questions arose: - jst want to confirm: it is possible to directly connect the mega32 to the L6203s to drive the motors right? *looks nervous.. what we have atm is the bidire
2006-08-27 by dlc
Good point - Most motors we use in robots and whatnot are pretty "poor" motors that don't work all that well at PWM over about 2KHz, so if you keep your PWM at 1KHz or lower then any H-bridge will work out fine for you - I tried 20KHz once on a TI 754410 and literally blew the to
2006-08-27 by David VanHorn
On 8/27/06, dlc wrote: > > The enable is where the PWM goes, the IN1 and IN2 determine motor > direction. It says that it is crossover protected so you don't need to > worry about turning on both FETs in either leg - Beware: Most bridges have a maximum chopping speed. Beyond that
2006-08-27 by dlc
The enable is where the PWM goes, the IN1 and IN2 determine motor direction. It says that it is crossover protected so you don't need to worry about turning on both FETs in either leg - I didn't look too closely, but I assume that if both are set the same (low or high) then eithe
2006-08-27 by Roy
The dragon programmer is due out very soon. Not shore if it supports high voltage programming though :-( Check out the discussion on AVR freaks. Listed at digikey - they estimate a shipping date 25th September http://www.digikey.com/scripts/DkSearch/dksus.dll?Criteria?Ref=46695 &
2006-08-27 by Mark Jordan
I'm a big fan of this one: http://elm-chan.org/works/avrx/report_e.html Works 100%. The command line program can be called by any text editor. Even the source code is available. Mark Jordan On 27 Aug 2006 at 23:25, Ranjit Puri wrote: > Hi, > > I have been using Tinies for a while
2006-08-27 by Ranjit Puri
Hi, I have been using Tinies for a while... All was fine till I lost my STK500 a few days ago, now I cant use the reset pin on my Tiny13 as I/O, coz my other programmers cant do High Voltage Serial Programming :-(. Does anyone know of a good High Voltage Serial Programmer that ca
2006-08-27 by Tom Becker
> ... using timer1 to generate our pwm signal and [] one or the other of the OC1 pins to change direction... There are two common PWM motor drive techniques, usually called Sign-Magnitude and Antiphase (or Push-Pull). In my experience, these two methods of PWM motor speed control
2006-08-27 by Larry Barello
Check out www.barello.net/Papers/Motion_Control I find that using the ENABLE input gives less control over the motors. After you have puzzled through the paper, above, then look at www.barello.net/Papers/H-bridge.pdf The hand drawn graphs in that paper were taken directly from an
2006-08-27 by katraven1
thx for that help =) *feeling very n00b... jst wanna confirm: we're using an L6203 for each H-bridge, which has 1 enable and 2 inputs. Am i right to say that the two inputs change the direction of the motor? as in, if i put the PWM into input1, it'll go one way and vice versa if
2006-08-26 by dlc
The Mega32 has two PWM channels (OC's) that you should use for motor speed. Use one or two of the other IO lines per H-bridge to select the direction. DLC katraven1 wrote: > we have an ATmega32 connected to 2 H-bridge circuits for 2 DC motors > which need to be reversible.. > > w
2006-08-26 by katraven1
we have an ATmega32 connected to 2 H-bridge circuits for 2 DC motors which need to be reversible.. we're using timer1 to generate our pwm signal and my idea was to use one or the other of the OC1 pins to change direction. would there be a better method of doing this? using my cur
2006-08-24 by moemen issa
they were just making updates man stevech11 wrote: avrfreaks.net down? --------------------------------- Do you Yahoo!? Get on board. You're invited to try the new Yahoo! Mail. [Non-text portions of this message have been removed]
2006-08-24 by John Samperi
At 02:58 PM 24/08/2006, you wrote: >Looks like it to me. My browser says "Can't load any data >from this site" Still down, fortunately it was working this morning so I had my morning fix.... :) hope they get it going before the end of the day. Perhaps they may be doing a switch o
2006-08-24 by Jim Wagner
On Thu, 24 Aug 2006 05:28:36 -0000 "stevech11" wrote: > avrfreaks.net down? > Looks like it to me. My browser says "Can't load any data from this site" Jim, KA7EHK --------------------------------------------------------------- The Think Different Store http://www.thinkdifferents
2006-08-24 by stevech11
avrfreaks.net down?
2006-08-22 by John Samperi
At 05:42 AM 19/08/2006, you wrote: >I wonder if somebody could help me looking for Scrolling Led Sign >software by AT90S2313 Do you mean you want to build something like these? http://homepages.chilli.net.au/~ampertronics/signs.htm Regards John Samperi ***************************
2006-08-19 by Naveen Koul
hi, is there any difference in the makefile that is to created for c and c++ files. as i have file name.cc should i direclty add in make file SRC = name.cc or name.cpp i dont how to do it for c++ files. Regarding my own templates can you give me a better idea on it so that i can
2006-08-18 by musabfakhri
Hi Friends, I wonder if somebody could help me looking for Scrolling Led Sign software by AT90S2313 .Note that by this software we can get on sign what we loading amicro as writting .for instance: when I just write "Hello" it well be shown on signas "Hello"............. I`m waiti
2006-08-17 by Ned Konz
Naveen Koul wrote: > hi, > > I would like to know how does the code starst up. from which function it > gets address of the main function. does there need of any boot loader for > it. or there is some start up code. what exaclty is the startup code does it > have init levels into
2006-08-17 by Ned Konz
Naveen Koul wrote: > can we use templates in avr gcc. Yes, but... You'll have to write your own. Forget about standard compliance, because... The C++ standard library is not available, so you won't have the STL available. Nor the various support functions You may have to write yo
2006-08-17 by Jim Wagner
Naveen - There is an avr-gcc forum on the AVRFreaks website. That is the best place to ask questions above gcc! Jim On Thu, 17 Aug 2006 12:50:38 +0530 "Naveen Koul" wrote: > hi, > > can we use templates in avr gcc. If yes then how. > > Regards > > Naveen > > > [Non-text portions
2006-08-17 by Russell Shaw
Doug Locke wrote: > -----Original Message----- > From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com]On Behalf > Of Russell Shaw > Sent: 16 August 2006 01:52 > To: AVR-Chat@yahoogroups.com > Subject: Re: [AVR-Chat] General purpose amplifier to use with AVR > > > Doug
2006-08-17 by Naveen Koul
hi, I would like to know how does the code starst up. from which function it gets address of the main function. does there need of any boot loader for it. or there is some start up code. what exaclty is the startup code does it have init levels into it . Regards Naveen [Non-text
2006-08-17 by Naveen Koul
hi, can we use templates in avr gcc. If yes then how. Regards Naveen [Non-text portions of this message have been removed]
2006-08-17 by Roy E. Burrage
That was a nice little function they began putting in their tube type scopes back in the 300/500 series days and have carried forward to their current models. Makes a really nice buffer amplifier. 7000 series can be had for a song these days but be careful that you buy one that w
2006-08-16 by moemen issa
I think that the amplifiers from Texas Instruments can do what you want ,they have a very big collection of amps of different bandwidths...for more info see digikey catalog Doug Locke wrote: Thanks Russell Anything with a bandwidth up to say a Mhz would be fine for this. I was ra
2006-08-16 by David VanHorn
On 8/16/06, Doug Locke wrote: > > Thanks Russell > Anything with a bandwidth up to say a Mhz would be fine for this. I was > rather thinking along the lines of obtaining something general where I had > no need to worry about design for now and that would also be an asset for > fu
2006-08-16 by erikc77099
--- In AVR-Chat@yahoogroups.com, "Doug Locke" wrote: > > I wonder if someone could help me with some advice please. I am trying > to use an AVR microcontroller to monitor an analogue signal. The > signal is both very low and of high impedance, so initially I wish to > experiment
2006-08-16 by Doug Locke
Thanks Russell Anything with a bandwidth up to say a Mhz would be fine for this. I was rather thinking along the lines of obtaining something general where I had no need to worry about design for now and that would also be an asset for future work. Once I have established the fea
2006-08-16 by barbara_barbara13
very good ,Ilike,studio,I think you very sturdy,
2006-08-16 by Jim Wagner
I can only say that I have had products with basic 8051 micros that failed. I have also had ones with switching power supplies fail. Power consumption is not a good indicator. I would NOT use UL as a FCC testing lab. ETL I don;t know about. There is a group of test houses in the
2006-08-16 by Russell Shaw
Doug Locke wrote: > I wonder if someone could help me with some advice please. I am trying > to use an AVR microcontroller to monitor an analogue signal. The > signal is both very low and of high impedance, so initially I wish to > experiment a little by using a general purpose a
2006-08-16 by Don Kirby
From what I'm reading in part 15, only devices drawing less than 6nW are exempt, although that might actually be a typo (6*m*W). There are other exempt devices, which mine might actually be one of. I;m not much for the legaleze of government documents, but I'm muddling through it
2006-08-16 by Roy E. Burrage
Have you spoken with the FCC recently Jim? I spoke with them a couple of years ago and with today's electronics being so low power they allow some producers and manufacturers to do self certification...or so I was told. It seems to depend on the application...i.e. if it's connect
2006-08-15 by Jim Wagner
You want 47cfr15.13 (part 15, section 13). Unfortunately, testing costs pretty big bucks ($1K to $2K). This is not something you can do yourself; it has to be done by an FCC certified lab. Depending on where you are in the U.S., I can offer at least one recommendtion. I can also
2006-08-15 by Doug Locke
I wonder if someone could help me with some advice please. I am trying to use an AVR microcontroller to monitor an analogue signal. The signal is both very low and of high impedance, so initially I wish to experiment a little by using a general purpose amplifier between the sourc
2006-08-15 by Don Kirby
Thanks Jim, I knew there was some kind of legal testing protocol to follow. I'm checking out the FCC part 15 right now. -Don --- In AVR-Chat@yahoogroups.com, "Jim Wagner" wrote: > > You need to be aware of FCC testing rules! They are spelled > out in FCC part 15 and I will provid
2006-08-15 by Jim Wagner
You need to be aware of FCC testing rules! They are spelled out in FCC part 15 and I will provide a link when I can look it up. Technically, you CANNOT sell a digital device with a "clock" in it that runs over a certain frequency without FCC certification. You can produce up to 2
2006-08-15 by Don Kirby
I've been developing an embedded device for some time now, and have decided to manufacture a batch for sale to the public. Although I have tested it as thoroughly as I possibly can, I would like to do more before offering it for sale (an ounce of debugging is worth a pound of bug
2006-08-14 by Ralph Hilton
On Mon, 14 Aug 2006 20:30:07 +0200 you wrote: >I would like to sell a board with an Atmega128 and my customer should not be able to read and program my software updates. I myself want to program and update that chip whenever I want. >Any ideas? > >Thanks > >Eric Use an encrypted
2006-08-14 by Don Kinzer
--- In AVR-Chat@yahoogroups.com, Ralph Hilton wrote: > Use an encrypted bootloader. Atmel has two application notes on this topic. See AVR230 and AVR231. You should be able to find the by Googling for those designators. Don Kinzer ZBasic Microcontrollers http://www.zbasic.net
2006-08-14 by Peter Harrison
Mark Jordan wrote: > On 14 Aug 2006 at 16:51, Peter Harrison wrote: > >> Mark Jordan wrote: >>> I'm looking for a 32-bit Square-Root Assembler routine >>> for the ATMEGA162 processor. >>> >>> Have adapted a 16-bit routine I found on the net, but >>> is is very slow. >>> >>> Any i
2006-08-14 by John Samperi
At 04:30 AM 15/08/2006, you wrote: >my customer should not be able to read and program my software updates Don't give out the update file to your customer. Regards John Samperi ******************************************************** Ampertronics Pty. Ltd. 11 Brokenwood Place Bau
2006-08-14 by Bruce Parham
That is what the protect bits are for... Bruce Erich Ludwig wrote: > I would like to sell a board with an Atmega128 and my customer should not be able to read and program my software updates. I myself want to program and update that chip whenever I want. > Any ideas? > > Thanks >
2006-08-14 by Erich Ludwig
I would like to sell a board with an Atmega128 and my customer should not be able to read and program my software updates. I myself want to program and update that chip whenever I want. Any ideas? Thanks Eric [Non-text portions of this message have been removed]