Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [atmega]

ATmega is a family in the AVR series of Atmel microcontrollers. It is the main microcontroller of the Arduino prototyping platform. Please specify the specific part number in your question.

The ATmegas are 8-bit RISC microcontrollers using a Harvard architecture. They have 4 to 256 kB program memory. Like all Atmel AVR microcontrollers, they are supported by various (open) toolchains. Most s are based on an chip.

They are the bigger brother of the microcontrollers, and have more memory and features.

Further reading:

related tags:

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How can I get my atmega328 to run for a year on batteries?

Scenario I have created a nice electronic door lock for my dorm room. It is currently an Arduino Diecimila with a servo [un]locking the door. It has a numerical keypad with 3x4 buttons and 5 LED's (2 serie pairs and one single LED). It also…
Pangolin
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What happens if I omit the pullup resistors on I2C lines?

Just now I realized that the I2C data and clock lines (SDA and SCL) must have pullup resistors. Well, I've built a couple of clocks using the DS1307 RTC (see datasheet) according to the schematic below. Notice that I have omitted both pullup…
Ricardo
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ATMega8: why do VCC and AVCC have to be connected?

I often read that it is good practice to connect VCC with AVCC. Even in the ATMega8 datasheet it says so: AVCC is the supply voltage pin for the A/D Converter, Port C (3..0), and ADC (7..6). It should be externally connected to VCC, even if the …
Peter
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Using the ATMega328 with the internal oscillator?

I have a project that I think would be best suited for an ATMega328P. However, in every simple project I've seen, people always hook up a 16MHz external oscillator. From what I can see, it should have an 8MHz internal oscillator. My project doesn't…
Earlz
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How do I read digital input on ATmega16?

What do I have to do to read a digital input (pushbutton) on ATmega16? Do I have to enable pullup-resistors or can I use a 10 kohm one? What would some simple code be be? Just a simple 'Turn the LED on when it's pressed thing'. Is there a beginner's…
curious
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Reading a huge number of analog sensors in real time

I'm trying to build a MIDI-like controller that has a neck like a guitar. On that neck, there is a huge matrix of pressure sensors. The controller will emulate 3 strings. The way this works is: There are 3 long strips of double sided copper tape…
d.oelert
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How can I use my SMD Arduino to program a separate DIP ATmega328?

I have an arduino with a surface mounted (SMD) microcontroller: I know how to use a DIP arduino as a programmer for a DIP ATmega328. It's easy --you just pop your microcontroller in the holder. However, with a surface-mount Arduino, there's no…
Manishearth
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Protecting AVR flash from reading through ISP?

I'm trying to protect whole flash from reading through ISP. It has bootloader, able to self program application section. Setting lock byte to: LB1/LB2 will not let user to use bootloader to upload new firmware. BLB12/BLB11 and BLB01&BLB02 will…
Pablo
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What is the minimal set of parts for a circut with this AVR microcontroller?

My Arduino Uno has a ATMEGA328P-PU microcontroller, and bunch of other stuff on the board. I'd like to program the chip without the Arduino software, and only the minimum of other components. I want to eventually create things without the cost of…
Rob N
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How can V-USB screw up the built-in SPI of an ATmega328p?

I'm working on a V-USB project that shows up as a Keyboard using an ATmega328p. The USB part is working great (it's not my first V-USB project), but after I start the V-USB stack with usbInit(), all calls to the SD card library fail. If I call the…
dnet
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Driving DC motors with MOSFETs and a microcontroller?

I'm developing a nano quadcopter using an Atmega328 microcontroller, powered at 3.3V, and very small brushed DC motors. The average current used by these motors is about 800mA @ 3.7V. Initially, to drive them, I used an L293D motor driver but this…
supergiox
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How should one switch from using an Arduino as a programmer to an external programmer?

Part two of a three part series on transitioning from Arduino to a plain AVR microcontroller and minimum supporting components (part one, part three) I've seen a lot of people ask this on the Internet, so here goes: I already know how to program…
Manishearth
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TQFP and VQFN on same footprint: good idea or bad?

In order to ease supply issues, I am considering an overlapping footprint for the TQFP-32 and VQFN-32 packages of ATmega48/88/168/328 CPUs. The two packages have the same pinout. It's a commercial project, likely to make a few thousand units over a…
jonathanjo
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Do the new "PB" variants of ATmega have a bug in the brown-out detector?

We've been using ATmega48/88/168/328 microcontrollers successfully for many years in many of our products. We have now considered to switch from the A and PA variants to the new PB variant (because we will need the extra pins, timers and UARTs in…
vsz
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How do you determine if a new microcontroller is defective?

I've never dealt with parts being defective strait from digikey, but 3 new Atmel ATmega164A's that I've received have been exhibiting extremely odd behaviour. I narrowed it down to something to do with the clock and it turned out that the resulting…
Jon L
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