Yahoo Groups archive
Messages
Page 178 of 307 · 15341 messages matched
2005-12-12 by spotwl8
hi! i'm new here. i need your help. i'm currently having a project on avr. i would like to communicate data from pc to microcontroller. the transmitter is connected to the pc through serial port. and the receiver is connected to the microcontroller. I used atmega16. when i progra
2005-12-11 by Don Kinzer
--- In AVR-Chat@yahoogroups.com, "nzrh2003" wrote: > Can anyone help with an example of seting up an A/D conversion in > assembler using the 5v supply as the reference. The basics of setting up an ADC conversion are described in the AVR datasheet including some C and assembly lan
2005-12-10 by Kevin Bentley
Here's some code I recently wrote for a tiny13. It uses the internal 1.1v reference, so you'll need to use a different value for ADMUX I think.: ; use the internal 1.1v reference. select ADC2 (charger2 input) ldi Temp,(1 ; Start a read on ADC1 ldi Temp,(1 WAITFORCHANNEL2: in Temp
2005-12-10 by nzrh2003
Newbe to Atmega. Can anyone help with an example of seting up an A/D conversion in assembler using the 5v supply as the reference. I want to do a simple conversion fo 5v signals to digital. Thanks in advance.
2005-12-09 by MuRaT KaRaDeNiZ
are you worried about noise or timing? In terms of timing, the occurance of interrupts will not interfere with A/D conversions, as all the timing of A/D module is generated by itself, no cpu cycles is needed for this. interrupts will only slow down your average A/D conversion rat
2005-12-09 by MuRaT KaRaDeNiZ
Hello, Google this: "Realtime oscilloscope GUI library for data acquisition " it is a dll you can use it from multiple programming languages visual c,delphi, borland c, simulink demo projects are available. you can check them and quickly use it in vb. Regards Murat Karadeniz http
2005-12-07 by erikc
Mark Graybill wrote: > 20V of ripple is pretty high, getting it down to something like a > volt or two would result in a cleaner image. The problems you're > complaining of aren't related to ripple, however. > > If your CRT is of the flat-screen variety then focus voltage will >
2005-12-07 by stevech@san.rr.com
if this is a hobby thing, just purchase a NetCallerID unit ($10) and connect its serial data port to the RS232 port of the AVR. I� have visual basic 6 code running on Windows'for this unit interfaced to my home automation PC.� It logs all calls, speaks the caller's name based on
2005-12-07 by Mark Graybill
20V of ripple is pretty high, getting it down to something like a volt or two would result in a cleaner image. The problems you're complaining of aren't related to ripple, however. If your CRT is of the flat-screen variety then focus voltage will need to be adjusted depending on
2005-12-07 by James Washer
Anyone here built an AVR based caller id unit? If so, did you use a callerid chip? Which one? Any URL's to your project?
2005-12-07 by Jim Wagner
Arif - The tube should be fairly tolerant of ripple on the high voltage. There is proabably something else going on. Watch out for your transformer! It can generate a magentic field that effects the tube. Jim On Wed, 7 Dec 2005 11:45:19 +0200 "Arif YILMAZ" wrote: > Thank you Mike
2005-12-07 by Arif YILMAZ
Thank you Mike and Jim, I am driving the crt in XY mode I don't use any raster actually I used a previously available schematics for the tube, the power supply may have problems as you stated, I previously inspected those signals and, tube is driven with 1400 volts anode-cathode
2005-12-06 by Jim Wagner
Arir - Here is some more information about CRTs. Magnetic susceptability (interferance) is very common with CRT. Most manufacturers put a metal magnetic shield over the tube. Often, it is a special metal (one has a trade mark of "mu-metal", I believe). With home TVs, the color on
2005-12-06 by Mike
Arir, To me, without knowing all the details, it sounds like Power Supply issues as all symptoms can be effected by the power supply. That gives you a commom factor. At least it's a place to start. Using your trouble shooting O-scope and voltage meters you should be able to track
2005-12-06 by Ralph Hilton
On Mon, 5 Dec 2005 10:55:06 -0800 you wrote: >I'm just starting to play around with sine waves using PWM and a lookup table. > >I'm concerned as to the maximum frequency of a sine that can be generated. Walking through an example, based on Fast PWM. > >Xtal=9830400Hz >8bit Fast P
2005-12-06 by John Samperi
At 09:49 AM 6/12/2005, you wrote: >I tied them to ground using 2.2Kohm.. No need to do anything, the displays have built in pull up resistors. At least I have never had to do anything and haven't had any problems with the brands I have used :-) Regards John Samperi **************
2005-12-05 by James Washer
I tied them to ground using 2.2Kohm... but that was just what I had on the bench at the time. I don't think it's all that critical.. - jim On Tue, 6 Dec 2005 00:25:21 +0200 "MuRaT KaRaDeNiZ" wrote: > Hi, > in 4bit mode where should we connect the unused bits? > > -----Original Me
2005-12-05 by MuRaT KaRaDeNiZ
Hi, in 4bit mode where should we connect the unused bits? -----Original Message----- From: "James Washer" Sent: 27.11.05 01:11:36 To: "AVR-Chat@yahoogroups.com" Subject: Re: [AVR-Chat] Help debugging LCD display issues Nice tip... thanks... as it turns out.. I think the problem w
2005-12-05 by James Washer
thanks... I wasn't aware of these. - jim On Mon, 5 Dec 2005 23:38:01 +0200 "MuRaT KaRaDeNiZ" wrote: > Hello, > > There are other choices: > Check the avr tiny series. There are devices with special high speed pwm > peripherals. These micro(s) (I dont remember exact part number) h
2005-12-05 by MuRaT KaRaDeNiZ
Hello, There are other choices: Check the avr tiny series. There are devices with special high speed pwm peripherals. These micro(s) (I dont remember exact part number) have a pll clock multiplier built in, just to generate high clock frequency for this demanding peripherals, you
2005-12-05 by Jim Wagner
I'm working on a project with similar constraints (even uses 2200Hz as one of the tones). There are not very many ways to improve things. I am using an 6-bt R-2R DAC driven by six port pins. Since the DAC output only has small steps in it, the harmonic content is much lower and t
2005-12-05 by James Washer
I'm just starting to play around with sine waves using PWM and a lookup table. I'm concerned as to the maximum frequency of a sine that can be generated. Walking through an example, based on Fast PWM. Xtal=9830400Hz 8bit Fast PWM This gives PWM frequency of (9830400/256) 19200Hz.
2005-12-05 by Jim Wagner
Hello, Arif - The very first question is about your CRT. Is it a raster-scan device (like a monitor or TV) or is it XY (like a real oscilloscope). I have some experience in this area as I did some design of oscilloscope circuits at Tektronix, though many years ago. Jim ----------
2005-12-05 by Arif YILMAZ
Hello to all Experts, I would like to refer to your information about oscilloscope CRTs. I have to use a crt do display waveforms like an oscilloscope but having really big problem with this sacred device. I used already available crt driver circuit with transistors and my wavefo
2005-12-04 by Dave Hylands
HI, On 12/4/05, Larry Barello wrote: > The only way to get the PC is to interrupt the processor. The PC will be on > the stack upon entry into the ISR. WDT will reset the processor and you > will lose your PC. Every time you call a subroutine, the PC is pushed onto the stack. The
2005-12-04 by Larry Barello
The only way to get the PC is to interrupt the processor. The PC will be on the stack upon entry into the ISR. WDT will reset the processor and you will lose your PC. The simplest way to debug something like this is a hardware debugger: JTAG or ICE200 (if it is a really old chip!
2005-12-04 by Ralph Hilton
On Sun, 04 Dec 2005 14:48:19 -0000 you wrote: As you noted the ADC can be run with a faster clock. If you only need a few bits resolution then I don't see why there should be a problem. 200KHz gives 10 bits. >I have an ATmega128 in an existing circuit that reads the value of a >r
2005-12-04 by Rick Collins
I have an ATmega128 in an existing circuit that reads the value of a resistor in an attached cable to determine the identity of an attached device. This has worked well, but they are out of resistor values that they can easily distinguish. I am considering the Dallas OneWire devi
2005-12-04 by James Washer
Did you ever get an answer to this? Seems to me you want to use either the WDT, or an external interrupt. Exactly what will be in the stack will depend on what compiler/library routines you are using.. but you should be able to determine this by looking some disassembled ISRs. On
2005-12-01 by Terry Slocum
I'm trying to track down a bug in an existing program. I believe it is getting stuck in a loop. Once the error occurs the only way to restore communication is to reset the processor. It would help a lot if I could locate the place in the code where it is getting stuck. I would li
2005-12-01 by James Washer
I don't see that a mega8 has the diff (gain) mode On Thu, 1 Dec 2005 18:52:46 +0200 "MuRaT KaRaDeNiZ" wrote: > But be aware that the analog bandwith falls when internal gain is > enabled: > > >From AVR120 (doc2559.pdf): > > "When using single-ended mode, the ADC bandwidth is limi
2005-12-01 by MuRaT KaRaDeNiZ
But be aware that the analog bandwith falls when internal gain is enabled: From AVR120 (doc2559.pdf): "When using single-ended mode, the ADC bandwidth is limited by the ADC clock speed. Since one conversion takes 13 ADC clock cycles, a maximum ADC clock of 1 MHz means approximate
2005-11-30 by Mehdi Ghassemi
Hi jim the atmel company has guarantied vref=2.3v for ref pin,ofcourse i use 1.25v and I dont have problem,but you can use 200x internal gain in atmega8 and Vref=Avcc,therefor you can't 0.1V for Vref because the ADC can't work, --- MuRaT KaRaDeNiZ wrote: > Hello James, > > Some s
2005-11-30 by Nailson Roveta
please help me what is wrong in that program? the led doesn't turn off placing 5v in the pin 1 even in an AT90S4433 or atmeg8 it works excuse my English $regfile = "at15def.dat" $crystal = 1200000 Config Portb.0 = Input Config Portb.1 = Output Do If Pinb.0 = 1 Then Reset Portb.1
2005-11-30 by MuRaT KaRaDeNiZ
Hello James, Some suggestions: Choose a voltage reference implementation with minimal noise, since now 100uV noise becomes 1bit of the result, and simple voltage references/regulators surely have more noise than that. Make use of RC filtering on reference voltage. if you use simp
2005-11-30 by Don AE5K
Many of us work in the field of product development for either ourselves or a company. Pause for a moment to consider the tough job of selling our pride and joy to the end user...marketing's task: Marketing's Glossary of Product Terminology =======================================
2005-11-27 by Zack Widup
On Sun, 27 Nov 2005, James Washer wrote: > I need to measure voltages in the 0-50mV range. I suspect the answer here is to use an amp > to get this to a more reasonable level (say 0-2.5V) however I was wondering if it is ok to > just supply AREF to 0.1 volts.. I suspect this is a
2005-11-27 by James Washer
I need to measure voltages in the 0-50mV range. I suspect the answer here is to use an amp to get this to a more reasonable level (say 0-2.5V) however I was wondering if it is ok to just supply AREF to 0.1 volts.. I suspect this is a bad idea, but I wanted to know for sure. thank
2005-11-27 by Arif Deshmukh
Hi, Which LCD you are using and what make. Bye On Sat, 26 Nov 2005 amol_deshmukh wrote : >hi > i was stuck up with LCD for about half a month for a very small reason. i too had done everything correctly. > i was trying to use LCD with AtMega16 in 4 bit mode using Port C. the JTAG
2005-11-26 by James Washer
Nice tip... thanks... as it turns out.. I think the problem was that I'd left D[0..3] floating on the LCD On Sat, 26 Nov 2005 09:58:37 -0800 (PST) amol_deshmukh wrote: > hi > i was stuck up with LCD for about half a month for a very small reason. i too had done everything correct
2005-11-26 by James Washer
Problem solved.. as usual, I changed more than one thing at a time... but problem may have been related to my having left D[0,3] floating.. Go figure Thanks for everyone's help. - jim On Fri, 25 Nov 2005 20:52:52 -0600 David Kelly wrote: > > On Nov 25, 2005, at 3:50 PM, James Was
2005-11-26 by amol_deshmukh
hi i was stuck up with LCD for about half a month for a very small reason. i too had done everything correctly. i was trying to use LCD with AtMega16 in 4 bit mode using Port C. the JTAG bit on Port C wasnt diabled and for this tiny thing could not get LCD running. u might wanna
2005-11-26 by Robert Diamond
On 26 Nov 2005 16:57:22 -0000, AVR-Chat@yahoogroups.com wrote: > Message: 1 > Date: Fri, 25 Nov 2005 13:50:35 -0800 > From: James Washer > Subject: Help debugging LCD display issues Coincidentally, I spent a few hours last night working with Peter Fleury's library, from a mega8 t
2005-11-26 by Dave VanHorn
--- In AVR-Chat@yahoogroups.com, James Washer wrote: > > Yes, I'm beginning to think that is the case. Thanks These display controllers are very picky about timing. Make sure that you are respecting ALL the timing constraints between the signals.
2005-11-26 by James Washer
Yes, I'm beginning to think that is the case. Thanks - jim On Fri, 25 Nov 2005 20:52:52 -0600 David Kelly wrote: > > On Nov 25, 2005, at 3:50 PM, James Washer wrote: > > > I'm using an Optrex DMC16207 (HD44780) LCD display with a Mega32 > > and Peter Fleury's LCD library. > > > >
2005-11-26 by David Kelly
On Nov 25, 2005, at 3:50 PM, James Washer wrote: > I'm using an Optrex DMC16207 (HD44780) LCD display with a Mega32 > and Peter Fleury's LCD library. > > Using the include test file, upon power-up, the top row of the > display shows all 16 cells "lit" (darkened) with EVERY bit po
2005-11-25 by James Washer
I'm using an Optrex DMC16207 (HD44780) LCD display with a Mega32 and Peter Fleury's LCD library. Using the include test file, upon power-up, the top row of the display shows all 16 cells "lit" (darkened) with EVERY bit position darkened (i.e. a rectangle). The bottom row is blank
2005-11-23 by Russell Shaw
erikc wrote: > Russell Shaw wrote: > >>Ivan Vernot wrote: >> >>>Me Too. >>> >>>On 23/11/2005 8:10:54 PM, mrmicro@gamebox.net >>> wrote: >>> >>>>I've been getting "server cannot be found" for about 3 days, everyone >>>>else getting that too? >> >>Ok from here. >>http://www.avrfrea
2005-11-23 by erikc
Russell Shaw wrote: > Ivan Vernot wrote: > >>Me Too. >> >>On 23/11/2005 8:10:54 PM, mrmicro@gamebox.net >> wrote: >> > I've been getting "server cannot be found" for about 3 days, everyone >> > else getting that too? > > > Ok from here. > http://www.avrfreaks.net/ Isn't this the
2005-11-23 by Russell Shaw
Ivan Vernot wrote: > Me Too. > > On 23/11/2005 8:10:54 PM, mrmicro@gamebox.net > wrote: > > I've been getting "server cannot be found" for about 3 days, everyone > > else getting that too? Ok from here. http://www.avrfreaks.net/