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11 votes
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What's missing in this development board?

It is max232 ic. Which is used to convert the signals from the RS232 serial port to the proper signal which are used in the TTL compatible digital logic circuits.
Electron's user avatar
  • 2,076
10 votes
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Atmel SAM E70 (ATSAME70Q21, Cortex-M7) battery backup

The idea behind the Vbat input on chips such as the STM32 is that the RTC and other low-power peripherals will normally be powered from the main Vdd, automatically switching to Vbat when Vdd is absent....
Abe Karplus's user avatar
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10 votes
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Estimating the frequency at which your microcontroller is running

Take a look at the compiler output here https://godbolt.org/g/TxZSgt. Notice that the inner for loop and the asm("nop") lines ...
C_Elegans's user avatar
  • 2,901
10 votes

Increase memory of an ATmega32

Global variables/types Changing the type of global variables (e.g. use uint8_t or a similar 1 byte instead of long), or use bits to store boolean arrays. Remove static variables and replace them by ...
Michel Keijzers's user avatar
10 votes

How to make a PCB based on ATtiny easily updatable by end users?

Take a look a the micronucleus bootloader... https://github.com/micronucleus/micronucleus It allows an ATTINY to accept a code download over a (slightly hackey) USB connection. It is widely used and ...
bigjosh's user avatar
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9 votes

Is ESP8266 an AVR?

ESP family isn't a AVR! The Library you refere to is a Arduino IDE (Integrated Development Environment) library. The Arduino IDE has a hardware layer that gives it the ability to utilize several ...
MatsK's user avatar
  • 758
9 votes
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Internal RC clock on Atmega329 accuracy

Use a 32.768kHz crystal or tuning fork. It can run asynchronously and you'll save as much power as you can while still having a clock. The system clock will still use the internal RC oscillator.
uhours's user avatar
  • 671
9 votes
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atmel studio for mac

No, recent versions of Atmel studio are based on Visual Studio which is Windows only. You could run it in a virtual machine. But it's worth noting that Atmel studio uses avr-gcc and arm-none-eabi-...
Chris Stratton's user avatar
9 votes

Can an EEPROM be one-time-programmable?

I did find one for At25020B, but not for one with the NB suffix. Why would Atmel make a chip and not publish the datasheet? Why wouldn't they? Chips are often manufactured for specific customers ...
Marcus Müller's user avatar
8 votes
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Power consumption of Cortex-M7-based microcontrollers

Converted to answer. There are numerous devices in each family, so I took a typical device from each one: Atmel typical device: ATSAME70 series Tables are in section 56.3.4 for active mode. For ST:...
Peter Smith's user avatar
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8 votes
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Microcontroller not working as expected or crashes after a few days

Is it possible to stack and static data collide? Yes, that is entirely possible. Atmega has no dedicated stack space, so if you use too much of it, you will overflow and crash your static data. Try ...
Dmitry Grigoryev's user avatar
7 votes
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Is it possible to redirect print streams to debugger in Atmel system?

You can output messages and values to the output window with Atmel Studio 7 (it might work with other versions but I am running version 7.0.1006 and using Atmel ICE) by doing this: Create a normal ...
DigitalNinja's user avatar
  • 1,087
7 votes
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Finding the source of a Hard Fault using extended HardFault_Handler

So, here's the fun part: it may be impossible to cite exactly which line is throwing the fault. The reason is that a bug in your code may be causing a fault to appear elsewhere -or- the bug might be ...
pgvoorhees's user avatar
  • 2,526
6 votes
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Are commonly available microcontrollers hardwired or microcoded?

The PIC, the Atmel and 8051 are hardwired. CISC does NOT mean automatically that a processor has microcode. Moreover, as in many other technologies (FPGA vs CPLD vs processor vs DSP), the boundaries ...
Claudio Avi Chami's user avatar
6 votes
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ATMEL's ARM programming without ASF

The ARM architecture is substantially different than AVR, but you still have access to any internal registers by operating on their address. The AVR Way With AVR, you would have set the direction of ...
Kurt E. Clothier's user avatar
6 votes
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Microprocessors for multiple (~40) SPI devices?

Either use demultiplexers such as the 74HC138 for the slave select, or use diode-ORs with a matrix select. Or if the protocol allows for it, you could chain all the buttons together and use one long ...
Ignacio Vazquez-Abrams's user avatar
6 votes
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How to write a bootloader and drivers for ATtiny167

From reading through your question, and having looked through the micronucleus repository, your problem is down to fuses/clocks. Firstly, and while not immediately obvious (not documented anywhere ...
Tom Carpenter's user avatar
6 votes
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USB C atmel chip interface

To make correct Type-C connection to your battery-powered Atmel MCU, you need to ensure four things: Make sure that your battery is not connected to Type-C VBUS, never. So a transistor switch (or ...
Ale..chenski's user avatar
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6 votes
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What is the difference between these two attiny44a parts?

Those are date codes: They represent the 22nd week of 2017 and 19th week of 2016, respectively. (Thanks to Maple for the link.)
Dave Tweed's user avatar
  • 175k
6 votes

Atmel Chip not recognized as USB device. How to troubleshoot

Leaving the Vbus pin floating seems a bit strange. The datasheet shows this configuration: None of the configurations shown in the datasheet leaves the Vbus pin floating. Just try connecting it up ...
Richard the Spacecat's user avatar
6 votes
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Why I need capacitors on VCC?

(Thanks for all people commented, having my answer improved greatly). These are called bypass capacitors (see fragment from What-is-a-bypass-capacitor): A bypass capacitor is a capacitor that ...
Michel Keijzers's user avatar
6 votes
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How to make a PCB based on ATtiny easily updatable by end users?

To program the Attiny via USB, you'll need an external programmer, as you've noted: something like your arduino. Going that route makes no sense, because your programmer would be more capable than ...
Marcus Müller's user avatar
6 votes

Driving a 12 V DC pump using Atmega16 Microcontroller and a 2N2222a transistor but it is not working?

First, the transistor you have chosen may not be adequate for the job. You state that the water pump motor is rated 4.8 W and 12 V. This implies a rated current of 400 mA, not 0.4 mA. Now the 2N2222A ...
Math Keeps Me Busy's user avatar
5 votes
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Why does the ATTiny84 have both an analog comparator and an ADC?

Speed Since the comparator is always active and is effectively an analog circuit it can generate an output at any time regardless of the current CPU task. This can be used to generate an interrupt ...
Transistor's user avatar
  • 177k
5 votes

Can anything be done about this AVRISP mkII or is it dead?

I had a similar issue with the AVR ISP MKII when I first got it. I connected up the programmer, turned on the board (which was powered from an adjacent USB port), and pop. On my board the regulated ...
Tom Carpenter's user avatar
5 votes

Push button counting

You need to be aware that as written your code will spin around the while loop dozens if not 100's of times seeing the one or the other of the switches pressed. Since your IF statement only checks for ...
Michael Karas's user avatar
5 votes

Estimating the frequency at which your microcontroller is running

You can't test the speed of a microcontroller by measuring how long it takes to execute unknown numbers of instruction. There is no guarantee what exact instructions the compiler generates from your ...
Olin Lathrop's user avatar
5 votes

AT90USB162 not detected in windows

You need to pull HWB low while coming out of (power-on) reset, or else the bootloader will simply idle when it finds no valid program in flash.
FRob's user avatar
  • 598
5 votes

Increase memory of an ATmega32

Unfortunately, adding external program memory is not usualy possible with this kind of chip. You could conceivably read and execute code from an external flash, but it would likely be slow and ...
Tim Vrakas's user avatar
5 votes
Accepted

UART read consistently missing half of the transmitted bytes

The issue here is that both usart_write_buffer_wait() and usart_read_wait() are blocking. The USART hardware seems to have a 2 ...
Turbo J's user avatar
  • 10.4k

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