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2007-01-22 by Jim Wagner
I like 74LCX125. Gives you six converters in a package. They do it right! You can power them from 3.3V and both input and output are 5V tolerant. This lets you convert both ways. Jim On Sun, 21 Jan 2007 17:17:11 -0600 Thomas Keller wrote: > At a guess,m substitute a single 3.3 V
2007-01-22 by David VanHorn
On 1/21/07, np np wrote: > > I dont think I would use resistors as the R and C input would delay the > signal. Since the C on the inputs is a few pF, and you can use resistors on the order of 1k, why are you worried? A logic gate IC of some sort would be a better solution with lo
2007-01-22 by dlc@frii.com
I have used the resistor method with XBee 3.3v units with no problems. Remember that you only need them on your outputs to the device. Don't make the values too high or you could make the waveform distort at high data rates. DLC Dennis Clark dlc@frii.com via Palm TX -----Original
2007-01-21 by np np
I dont think I would use resistors as the R and C input would delay the signal. A logic gate IC of some sort would be a better solution with low value pull ups on the outputs. http://www.ckp-railways.talktalk.net/pcbcad17.htm David VanHorn wrote: Anybody know what the best way is
2007-01-21 by David VanHorn
On 1/21/07, Thomas Keller wrote: > > At a guess,m substitute a single 3.3 V zener diode for each voltage > divider. Ought to work (I think). Only potential problem I can see > is it could end up overloading the AVR outputs. You'll end up with each output trying it's hardest to pu
2007-01-21 by David VanHorn
Anybody know what the best way is to interface a 5V output on my Mega64 to a 3V input on a Nordic RF IC ? The Nordic datasheet specifies a max input voltage of VDD + 0.3V (3.3V) BTDT. > Best way I could come up with was a voltage divider on each line, but > theres six lines, so t
2007-01-21 by Thomas Keller
At a guess,m substitute a single 3.3 V zener diode for each voltage divider. Ought to work (I think). Only potential problem I can see is it could end up overloading the AVR outputs. tom kernels_nz wrote: > > Hey guys, > > Anybody know what the best way is to interface a 5V outpu
2007-01-21 by kernels_nz
Hi TVM, Theres a quite a bit of information out there on interfacing to SD Cards, when I did it a year or so ago, I found enough information on Google to get me going. Things to watch out for: - SD cards are not programmed byte by byte, they must be programmed in 512 byte pages.
2007-01-21 by kernels_nz
Hey guys, Anybody know what the best way is to interface a 5V output on my Mega64 to a 3V input on a Nordic RF IC ? The Nordic datasheet specifies a max input voltage of VDD + 0.3V (3.3V) Best way I could come up with was a voltage divider on each line, but theres six lines, so t
2007-01-19 by Dave Hylands
Hi David, > I know a number of people around here have written stuff to talk to > SPI-SD cards - is any of it GPL or anything so I can go get it to see > how it's done? There is some sample code for an ARM processor over here: http://www.sparkfun.com/commerce/product_info.php?pro
2007-01-19 by Bruce Parham
There are two SD links on SanDisk OEM manuals page @ http://www.sandisk.com/Oem/Manuals/ Neither is complete but it's a start. Good hunting, Bruce David Collier wrote: > not strictly a processor specific question, sorry, ( and if anyone knows > of a better place to ask it, please
2007-01-19 by timbomcnuckle
if his is not teh right place then kindly delete or ignore..but, I have some stuff I wanna get rid of.... Atmel AT91EVB- is older ARM evaluation kit in original box- comes with everything you would expect like RS232, power adapt cord, eval software suite and I'll include 5x newer
2007-01-19 by David Collier
not strictly a processor specific question, sorry, ( and if anyone knows of a better place to ask it, please tell ) I'm trying to build some s/w to talk to a MicroSD ( previously known as TransFlash ) card in SPI mode. There don't seem to be any published data sheets on the SanDi
2007-01-19 by Micro Brix
On 1/18/07, Roy E. Burrage wrote: > > You can do the same thing by writing program modules that are generic in > nature. After a while you have a library of modules that can be > messaged for a particular application as John stated. That Dave Van > Horn guy taught a lot of us som
2007-01-18 by Roy E. Burrage
You can do the same thing by writing program modules that are generic in nature. After a while you have a library of modules that can be messaged for a particular application as John stated. That Dave Van Horn guy taught a lot of us some good basic proceedures...even though we ma
2007-01-18 by np np
I go a bit further with this method and use a previous project as a template. I often find myself having the same subroutines in a lot of programs. This has the advantage of having fully tested code already written. http://www.ckp-railways.talktalk.net/pcbcad21.htm John Samperi w
2007-01-18 by John Samperi
At 03:27 AM 19/01/2007, you wrote: > > That is why I have adopted the practice of installing a > > full vector table, with all the standard labels and filling > > the unused ones with RETI or jump to an error handler. A practise that I have also adopted. With the AVR I have devel
2007-01-18 by Micro Brix
On 1/18/07, Thomas Keller wrote: > > Larry, > > Not wishing to start a language war here, but I have to say that I > have looked at doing C on the AVR, and frankly, it looks nastier than > working in assembler. I have vast experience in C programming on both > the Winblows and *n
2007-01-18 by Jim Wagner
This is where the line lables (as suggested in the device data sheet) really help. Jim On Thu, 18 Jan 2007 11:12:46 -0600 Thomas Keller wrote: > Absolutely! I had a fully implemented interrupt > vector table, I had > miscounted and had some rjmps where there ought to have > been
2007-01-18 by stevech11
re the below - Yes! I did asm on the AVR for a small project to get the feel for the flash vs. RAM architecture and the registers/addressing modes. But this was a small effort. Following lots of examples from others' work. I found that using WinAVR (GCC) with the AVR is best done
2007-01-18 by Thomas Keller
Larry, Not wishing to start a language war here, but I have to say that I have looked at doing C on the AVR, and frankly, it looks nastier than working in assembler. I have vast experience in C programming on both the Winblows and *nix platforms, as well as others, and I love C.
2007-01-18 by larry barello
That is why I use C. My time is way more valuable than processor time or space. -----Original Message----- From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf Of Jim Wagner Sent: Thursday, January 18, 2007 7:59 AM To: AVR-Chat@yahoogroups.com Subject: Re: [
2007-01-18 by Micro Brix
On 1/18/07, Thomas Keller wrote: > > Absolutely! I had a fully implemented interrupt vector table, I had > miscounted and had some rjmps where there ought to have been some > reti's, and vice versa. my interrupt vector table template will be > receiving full commentary TODAY to i
2007-01-18 by Thomas Keller
Absolutely! I had a fully implemented interrupt vector table, I had miscounted and had some rjmps where there ought to have been some reti's, and vice versa. my interrupt vector table template will be receiving full commentary TODAY to insure that this never happens again! (and,
2007-01-18 by Micro Brix
On 1/18/07, Jim Wagner wrote: > > That is why I have adopted the practice of installing a > full vector table, with all the standard labels and filling > the unused ones with RETI or jump to an error handler. The only way to fly! :) I've always done this, or a close variant. In s
2007-01-18 by Jim Wagner
That is why I have adopted the practice of installing a full vector table, with all the standard labels and filling the unused ones with RETI or jump to an error handler. Congrats, Jim On Thu, 18 Jan 2007 05:43:12 -0600 Thomas Keller wrote: > > ***ALRIGHT*** It's working!!!!!!!!!
2007-01-18 by Micro Brix
On 1/18/07, Thomas Keller wrote: > > > ***ALRIGHT*** It's working!!!!!!!!! YAY! :) [Non-text portions of this message have been removed]
2007-01-18 by Thomas Keller
***ALRIGHT*** It's working!!!!!!!!! Thanks, guys. It turned out I had three problems, one of which was in my debug routine (*doh*). The biggest problem, however, was that I had miscounted in my interrupt vector table, and it wasn't doing what I thought it was. *SHEEEESH* THANKS,
2007-01-18 by Roy E. Burrage
"Try not to develop too much at one time without testing." That's probably some of the best advice anyone could ever give. There's a reason we do programs in blocks, brix, and modules. As for Kat - I can only repeat...a real job, eeeewwww! REB Micro Brix wrote: >On 1/18/07, Roy E
2007-01-18 by Richard Reeves
Okay, for information, I'm running AVR Studio V4.12 build 490 here. My PC is an Athlon running at 1.4GHz. Apart from sorting out comments that had moved to the next line (otherwise it wouldn't assemble), I've just run it 'as-is' and taken some screen-grabs through the simulation.
2007-01-18 by John Samperi
At 06:46 PM 18/01/2007, you wrote: >I have a full time job now (doing low voltage cabling (Fire / EWIS / PA >/ Nurse call etc) ) so I am up at 5am to be on-site at 7am :) ahhh the good old Emergency Warning and Intercommunication System, spend 12 year of my life developing the FF
2007-01-18 by Roy E. Burrage
eeeewwww! A real job? That's disgusting! REB Kathy Quinlan wrote: >Roy E. Burrage wrote: > > >>Agreed, and that's one of the nice things about AVRs over those other >>guys...as well as simplicity of developing the hardware, which isn't >>always so easy to get started with over on
2007-01-18 by Richard Reeves
REB: > Perhaps Tom needs to set his timers to 1, any other associated variables > to 1, and step it through from there. As John Samperi stated earlier, a > delay of a few mSec in hardware at 4 MHz may take a couple of hours in > the simulator. As I said after Tom sent his code la
2007-01-18 by Kathy Quinlan
Roy E. Burrage wrote: > Agreed, and that's one of the nice things about AVRs over those other > guys...as well as simplicity of developing the hardware, which isn't > always so easy to get started with over on the dark side. > > Perhaps Tom needs to set his timers to 1, any other
2007-01-18 by Micro Brix
On 1/18/07, Roy E. Burrage wrote: > Agreed, and that's one of the nice things about AVRs over those other > guys...as well as simplicity of developing the hardware, which isn't > always so easy to get started with over on the dark side. > > Perhaps Tom needs to set his timers to
2007-01-18 by Roy E. Burrage
Agreed, and that's one of the nice things about AVRs over those other guys...as well as simplicity of developing the hardware, which isn't always so easy to get started with over on the dark side. Perhaps Tom needs to set his timers to 1, any other associated variables to 1, and
2007-01-18 by Micro Brix
> > So, there is no fundamental reason why the simulator won't do what Mr. > Keller needs done. None at all.. My first app in the AVR, delivered six weeks after I first saw the 8515's data sheet, was developed for four weeks in sim only while I waited for delivery of the first 85
2007-01-18 by larry barello
I agree that using a real chip is better. Using one with JTAG is even better because you can fiddle with the bits real-time and see what works. The AvrDragon is a killer product IMHO. That said, I developed my original RTOS (www.barello.net/Avrx) completely in the simulator. I le
2007-01-18 by Captain Impala
Hi Guys, I'd like to invite you to a robotic maze solving comp. I've attached a Word doc that is the maze comps entry info packet. I've also pasted the event flyer below. Thanks for your time. 2007 Robotic Maze Solving Comp April 28 2007 at 11am To be held at the Winfield VFW Pos
2007-01-18 by kernels_nz
Hi Tom - Not all the guys in the group will agree, but i'm still old-school. I like doing my debugging with a "real" chip and "real" led. But basically don't lose hope ! EVERY time that something in the AVR have not done what they were supposed to, it was my software that was at
2007-01-17 by Thomas Keller
Don: Yes, I am using both timwrs. one is as a tomer, the other as PWM. tom Don AE5K wrote: > > > Tom, > > I don't have time right now to go thru your code, but what I recall > seeing you posted a few days ago I noticed you initialized timer 0 but > later in program referenced tim
2007-01-17 by Don AE5K
Thomas Keller wrote: > > Someone (John Samperi?) asked how long I had waited to see if interrupts > were happening. The answer is a very long time. I even went so far as > to set the program to running, and going off to do other things for > almost an hour. I returned to find the
2007-01-17 by Micro Brix
On 1/17/07, np np wrote: > > It is sometimes sensible to go back to basics. > Start with a simple program that simply toggles a pin on interupt. > > If that is not happening then check global interupts are enabled. > Your timer interupt must be enabled too. > > Make sure that you
2007-01-17 by np np
You could use a thermistor in series with a capacitor. See how long it takes to charge up to see what the resistance is. This is a cheap solution I have used successfully many times. http://www.ckp-railways.talktalk.net/pcbcad28.htm mago Umandam wrote: you made sense.. no signifi
2007-01-17 by np np
It is sometimes sensible to go back to basics. Start with a simple program that simply toggles a pin on interupt. If that is not happening then check global interupts are enabled. Your timer interupt must be enabled too. Make sure that you reenable the timer int after the interup
2007-01-17 by Micro Brix
For a timer int: Global ints must be on. The specific int must be enabled. The timer must be in a mode that will actually cause the condition to occur. The prescaler must be set up to give the timer a clock source that is running. That's about it.. Make sure your vector table is
2007-01-17 by Thomas Keller
Someone (John Samperi?) asked how long I had waited to see if interrupts were happening. The answer is a very long time. I even went so far as to set the program to running, and going off to do other things for almost an hour. I returned to find the program still cycling rapidly
2007-01-17 by mago Umandam
you made sense.. no significant defference between the body and the pin temperature. thank you mago Jim Wagner wrote: Body. Usually, this is not a problem because temperature gradients are low in most situations. In this case pin temperature is not very different from body. Also,
2007-01-16 by dlc@frii.com
> > hello guys, > > i used a digital temp sensor to monitor a temperature of a certain ic > near to it. Now my question is that what part of the IC sense the > temperature? Is it their body? or a certain PIN? It is a sensor built into the silicon on the actual chip die. So basica
2007-01-16 by Jim Wagner
Body. Usually, this is not a problem because temperature gradients are low in most situations. In this case pin temperature is not very different from body. Also, most temperature sensors are only accurate to about 2C with a few to 0.5C. Jim On Tue, 16 Jan 2007 09:00:25 -0000 "ma