Comments on: Timers in Compare Mode – Part I

By: Awais Khan

Awais Khan — Sat, 21 Jan 2012 12:59:13 +0000

Hello
Timer tutorial was very beneficial to me. I wanna use AVR ATmega32 for page writing and page reading on AT24C1024 EEPROM. Is there any tutorial for that?

By: prakash

prakash — Wed, 11 Jan 2012 04:44:58 +0000

THnks,sir

By: vinayak

vinayak — Wed, 28 Dec 2011 06:11:22 +0000

hi Avinash
i am looking for touch screen interface to atmega32
can you give me suggestion for this type implementation or can you give demo board for this
please give me reply

By: matrix

matrix — Thu, 22 Dec 2011 06:27:57 +0000

MIND-BLOWING explanation…..u make topics so simple..doesn’t matter how hard the topic is. THUMBS UP 4 U. (*****)

By: Thong

Thong — Tue, 22 Nov 2011 14:13:01 +0000

Hi everyone
I don’t understand the thing which is written in ATmega128 Data Sheet page 93 :
“Changing the TOP to a value close to BOTTOM
when the counter is running with none or a low prescaler value must be done with care since the CTC mode does not have the double buffering feature. If the new value written to OCR0 is lower than the current value of TCNT0, the counter will miss the compare match. The counter will then have to count to its maximum value (0xFF) and wrap around starting at 0×00 before the compare match can occur.”
Why? and if in CTC mode have the double buffering. What is happen different?
Thanks

By: Armen

Armen — Mon, 11 Jul 2011 13:00:28 +0000

Tremendous Tutorial, clean, simple, easy to get, cool table color filterm, …
Thank you.
awsome job!

By: Eeshaanee

Eeshaanee — Mon, 13 Jun 2011 16:54:33 +0000

very nice tutorials….
really well explained..!!

By: AVR Timers - An Introduction. | eXtreme Electronics

AVR Timers - An Introduction. | eXtreme Electronics — Thu, 02 Jun 2011 04:33:13 +0000

[...] Timers in Compare Mode [...]

By: hans

hans — Fri, 18 Mar 2011 10:37:32 +0000

Well done! keep up the pace. we’re looking forward to get a pdf of this part and the next parts.

By: Avinash

Avinash — Fri, 21 Jan 2011 06:54:27 +0000

@Micro,

Thanks a lot for your feedback! Only people like you provide energy to keep me writing …

By: Micro

Micro — Fri, 21 Jan 2011 05:39:11 +0000

I have read both your timer tutorials. These are the best I found. After reading these I was finally able to understand the datasheets. This helped me a ton. Thanks

By: Siddhartha

Siddhartha — Sat, 08 Jan 2011 07:55:44 +0000

In case the following points help someone :

———————————————————–
“In the above setup if I vary OCR1B, will I get a Fast PWM on OC1B, whose duty I can vary independent of OCR1A.”

I tried. Yes it can be done.
———————————————————–
“In that case I can use OC1A and OC1B to drive the two ENABLE pins of LM293D (motor driver) independently.”

I have still not tried. But I am sure it can be done.
———————————————————–

By: Siddhartha

Siddhartha — Tue, 04 Jan 2011 05:45:07 +0000

The one of the very exceptional works I have ever seen on AVR tutorials.

Greetings for the new year to all.

I am using Atmega16 with 8 Mhz external crystal. I have been able to set the Timer1 prescaler and Fast PWM mode. By varying OCR1A and I could vary the duty of Fast PWM on OC1A.

My query is as follows :
In the above setup if I vary OCR1B, will I get a Fast PWM on OC1B, whose duty I can vary independent of OCR1A. In that case I can use OC1A and OC1B to drive the two ENABLE pins of LM293D (motor driver) independently.

Let me know if the above concept is valid.

Thank you.

By: sai

sai — Sat, 04 Dec 2010 05:46:20 +0000

damn good,really useful.clean ,ssimple,superb.thanks a lot

By: Mayank Sharma

Mayank Sharma — Tue, 19 Oct 2010 13:38:18 +0000

all these tutorials here are best on net

By: Interfacing Ultrasonic Rangefinder with AVR MCUs | eXtreme Electronics

Interfacing Ultrasonic Rangefinder with AVR MCUs | eXtreme Electronics — Thu, 07 Oct 2010 02:52:03 +0000

[...] Timers in Compare Mode [...]

By: William Lewis

William Lewis — Sat, 21 Aug 2010 16:44:42 +0000

Excellent.. Just what i was looking for

By: sam

sam — Tue, 06 Jul 2010 17:40:11 +0000

Hi
A wonderful job done by you.. amazing
I have made a program for my project in which i require the microcontroller to perform the following functions:
1)pulse generation
2)timer to ADC9220
3)data acquisition from the 12 bit adc.
can you check my code whether it is fine. i will be gratefull.

By: Mayank

Mayank — Tue, 08 Jun 2010 17:41:30 +0000

well, actually, i use a microcontroller development board, which I bought from somewhere else. They have attached the 4Mhz crystal and given to me. So, i feel that they have had preset the fuse bits for that. Anyways, i will recheck that part.

One reason that i could find for the slow process was a fault in the programming. 1sec = 100msec, but in your code (part II), 1000msec was used. But after that, the clock became too fast.. approx, it took 4sec to complete 10sec of display.

By: Avinash

Avinash — Tue, 08 Jun 2010 13:11:41 +0000

@Mayan,

Did you set the fuse bits for external crystal ???

Or just hooked a crystal and thought that MCU will switch from internal to external xtal automatically ???

Now don’t ask me that “what are fuse bit and how to set them!”

-admin