Refers to a crystal oscillator.

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0
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1answer
56 views

ATtiny44 millis() not working with 16 MHz external clock

I'm using ATtiny44 with Arduino IDE according to this tutorial: http://highlowtech.org/?p=1695 I have a problem with millis(). When I use an internal 1 MHz clock it works correctly but when I use ...
0
votes
1answer
75 views

How can you reduce the clock frequency of an Arduino Mega?

I'm trying to debug a problem and need to reduce the speed of the clock on my Arduino Mega from 16MHz to 8MHz. I can't find any simple way of doing so, so I wanted to know if there were any gurus ...
0
votes
1answer
32 views

How can you determine the duration of a timer interrupt?

So I understand that when setting a timer interrupt you don't use nanoseconds or milliseconds, but the actual number of clock cycles. However, I don't understand how you would be able to setup a ...
1
vote
0answers
58 views

Serial clock for SPI

I'm trying to configure my ADC(LM98725) registers through Arduino UNO via SPI but I'm facing a small problem, it would be great if somebody help me out. I have to configure my 16 bit ADC registers ...
1
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0answers
38 views

Serial Request error

I am working on arduino Uno board.I am trying to send request Serially from out Side using docklight.I am sending COmmand is request send every 5S to 10S and get response.When i tested this code with ...
5
votes
1answer
102 views

Syncing/taking external clock for SPI on Arduino Due

I have an Arduino Due with a SAM3X8E chip and am trying to read SPI data from an external source that is communicating in SPI. I was able to get data by identifying specific bytes that are identifiers ...
0
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0answers
58 views

ATMEGA328P 16Mhz External Clock serial bitrate mismatch (corrupt data)

I've been trying to get an ATMEGA328P communicating via a FTDI breakout board, and have run into something I can't seem to find much information about. When I have the ATMEGA running on its internal ...
4
votes
3answers
514 views

Confusion with ATmega328P and 3.3V/8MHz

Firstly, I have tried to set the bootloader to be 8MHz internal oscillator. I have tried the board setup from here - https://github.com/oshlab/Breadboard-Arduino. And also the breadboard-1-6-x.zip ...
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vote
2answers
95 views

What are the consequences of different clock speeds on different boards?

I am a programming amateur, arduino noob, trying to decide which board will be better for my project. I need a small board. I am trying to decide between the Teensy 3.2 and the RFduino. I want to have ...
1
vote
1answer
46 views

Why does the Pro Mini 5 v and 3.3 v version have different clock frequencies?

It looks like the 5 volt version used the 16MHz external crystal while the 3.3V one uses the 8MHz crystal. I need to use 3.3v as my operating voltage. Can I just remove the linear regulator and bring ...
9
votes
2answers
2k views

Why is there a clock in my arduino?

Of course I know it is usefull to control the time of a delay, but any other use? With a 16Mhz clock, each line of my program will take 1/16000000 second, right? even a very very big line will ...
1
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0answers
35 views

Arduino signed int can't fire timer > 15 seconds

I have tried to use different libraries like TimeAlarms , SimpleTimer, Timer and others. My goal is to call function periodically every minute or so. Each library works fine when repeat time is less ...
1
vote
1answer
93 views

What is the relation between Arduino's clock and possible VGA resolution?

I have seen it said over and over (in different places) that in order to achieve 640x480 resolution out to a DB15 VGA connection, the arduino would need to be clocked at 25Mhz or that at half ...
0
votes
5answers
120 views

Do I have to use an RTC to build a clock?

While I was researching ideas for an Arduino clock, I found several clocks that incorporated an RTC (Real Time Clock) module. I don't know why it is used in some clocks. So, here are my questions: ...
4
votes
1answer
39 views

Input clock limit

If you use an external oscillator, and divide-by-8 internally, can you apply up to 160MHz on PB6? For example, can I use my 50MHz oscillator to clock my 328p @ 6250KHz? Note: when I say oscillator I ...
1
vote
1answer
193 views

Arduino Due SPI speed reduction

I need to reduce the SPI clock speed of the Arduino Due down to about 100 kHz. Unfortunately my hardware doesn't support higher speeds. With the current maximum divider of 255, I can only reach a ...
2
votes
2answers
27 views

The Time are functions do not work correctly when the processor clock speed is set at 128K

How can I change The timers to work correctly when The processor clock is set to 128K instead of 16 M? At present, using the delay function does not work correctly, The delay is far too long.
2
votes
2answers
1k views

Arduino constant clock output

I am controlling an ADC with my Arduino Uno. I would like the clock of the ADC to be the same frequency of the Arduino. Is there any way that I can have a constant clock output from one of the Arduino ...
2
votes
1answer
120 views

Can I reuse crystal frequency of Arduino?

If I use some IC which requires clock frequency like 16MHz, can I take one from Arduino? Or this it too high frequency to travel to neighboring board?
1
vote
1answer
93 views

get current time in nanoseconds

On Arduino due, Is this possible to get the current time in nano seconds? At 84Mhz, I guess it will always be a multiple of ~12ns. And a perfect solution would read a register/variable rather than ...
6
votes
2answers
414 views

Arduino at 20 MHz?

I wonder why Arduino doesn't run at 20 MHz, the frequency the AVR is specified for. Now, running at 16 MHz, we're wasting 20% performance for nothing. I don't think there are any implications when ...
0
votes
2answers
134 views

How to upgrade Arduino UnoR3 clock

A little background: I need to generate a 40KHz frequency as accurately as possible. (One of my other posts is here: Stable frequency generation) My code is solid- I'm using an Uno R3 and ...
2
votes
2answers
121 views

time error in controlling a clock

I have designed and 3d printed a clock. I am controlling the clock using a Arduino sketch running on a Attiny2313. The stepper motor I am using is a 12v 1:12 ratio stepper. The total number of steps ...
0
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2answers
226 views

ATmega328P and other chip sharing clock

I am moving my Arduino project to another platform, operating at 3.3V. (5V from USB not useable due to some 3.3V-only chips in the design) Having read about this it seems that 12MHz is a good speed to ...
2
votes
2answers
352 views

Flashing a ATmega328 that came from an Arduino to not use an external oscillator

I have a ATmega328p chip from a kit that was supposed to be an Arduino compatible thing. I decided to go beyond Arduino and try to program the chip directly. I setup an UNO as an Arduino ISP, more or ...
7
votes
1answer
625 views

Can I program a 3.3v chip on a 5v board?

I bought a Gertboard a while ago, and one of the features it has on-board is an ATMega328 (DIP). However, since the Gertboard is designed for use with the Raspberry Pi, it only operates at 3.3v, so ...
5
votes
1answer
206 views

Can I link another device to the Uno's clock?

I'm trying to use an unusual 16x2 LCD display with my Uno. As far as I know, it's an EA-X16027AR. It doesn't seem to be compatible with the HD44780 driver, which is typically used for Arduino LCD's. ...