15
votes
Accepted
very lightweight low power microcontroller with memory?
I made up a small torch locator which used an ATtiny85 powered from a button-cell (CR2032). It looks like this:
Other side:
That currently weighs 5.9g. The battery-holder weighs 1.6g so you could ...
- 37.9k
12
votes
Arduino Pro Mini is burned by 12v. Can I save it?
1. Your microcontroller is probably/maybe fine; your tiny little voltage regulator is dead; here's why:
Sergio, yes, you can probably/perhaps save it: your Arduino (the microcontroller--ie: processor ...
- 1,359
11
votes
Pin 13 fires relay when powering on... How to disable?
There are three things you can do:
Remove the bootloader entirely and program the board with a hardware programmer (USB-ASP, Another Arduino, etc).
Edit the bootloader source, recompile, and ...
- 105k
9
votes
Accepted
Arduino 16 MHz with only 3.3V?
Officially, no. Practically, often but not always.
If I follow the datasheet to the the letter, this configuration should not work. BUT... After some test, it did work.
The data sheet does not ...
- 5,390
8
votes
very lightweight low power microcontroller with memory?
I would personnaly suggest an ATtiny 45/85. It is pretty much a small AVR with 5 GPIOs. You can program it with the Arduino IDE and use the Arduino as ISP. If you can design you own custom PCB, a SMD ...
- 2,913
7
votes
Why does this Arduino Pro Mini use a capacitor on the DTR reset line?
Most USB to serial chips set the DTR to LOW on connecting, but it keeps it LOW.
This would reset the arduino, but since the DTR never goes HIGH the Arduino will never get out of this reset state, ...
- 11.3k
6
votes
Getting "avrdude:stk500_recv(): programmer is not responding" while uploading sketch to Arduino Pro Mini
rx -> tx
tx -> rx
Please check your connections.
- 61
6
votes
Accepted
Powering from 3V coin cell to VCC, using I/O pin as supply GND
Can I use a I/O as (input/supply) GND?
You can use an I/O pin as a supply for another (low power) device, but
you should power the Arduino itself from its Vcc and GND pins.
I could use the reset ...
- 42.3k
6
votes
Accepted
How to power my Arduino mini using wall socket?
I have connected the Relay and IR receiver directly to the Arduino
mini. Pin 10-14 are used for the relays Ins and PWD 3 for IR output.
I hope you don't mean that you have connected the coils of ...
- 2,114
6
votes
Accepted
Pro Mini - Using RAW pin for 3.3v input
It is not ideal, no. The RAW pin first goes into a 3.3V voltage regulator whose dropout voltage is up to 200mV (worst case). That means that you would get around 3.1V out, and it wouldn't be ...
- 105k
5
votes
Audio Frequency White Noise generation using Arduino Mini Pro
Mike's answer uses a Fibonacci Linear Feedback Shift Register configuration, but the compactness Galois Linear Feedback Shift Register Configuration could be faster:
#define speakerPin 8
unsigned ...
- 2,332
5
votes
Mounting Arduino in an enclosure
What type of box?
Howmany times/how easily do you want to remove the Arduino Mini?
Hot glue
Hot glue is the way to go in many occasions.
It does not conduct electricity, so is pretty safe. (Please ...
- 2,695
5
votes
Accepted
Arduino PRO Mini - The pads [was "jumpers"] on the back and Low Power Consumption
Both responses are correct but be mindful that this is a SparkFun feature. An Arduino Pro Mini from China won't necessarily have the SJ1 pad.
1) Like Gerben said, the pads on the underside of the ...
- 66
5
votes
Arduino 16 MHz with only 3.3V?
According to the datasheet you need 3.78V to run at 16 MHz, and 3.3V isn't that far off. I would be surprised, for example, if it stopped working at 3.77V, because that would mean that the operating ...
- 37.9k
5
votes
Accepted
Measuring li-ion that arduino is running from
Using the 1.1V internal analog reference to measure a draining VCC
source by using a voltage divider on it
You could indeed use a voltage divider, and measure a scaled-down Vcc
against the internal 1....
- 42.3k
4
votes
Accepted
Soldering Arduino Pro Mini's disaligned pins
That's indeed quite an problem.
If you don't mind losing 2 analog pin, you could solder some jumper-wires between A4 and A2; and between A5 and A3. Then you could connect your I2C lines to pins A2 ...
- 11.3k
4
votes
Arduino 16 MHz with only 3.3V?
A little test, not very scientific, but shows it runs fine on 3.3V - https://www.youtube.com/watch?v=If0eOa0Uj5I.
Again, if you would like to stay withing the specification just use a "clock divider/...
- 579
4
votes
Accepted
Substitute for FTDI board?
All prices in USD w/ free shipping.
FT232RL breakout board:
Aliexpress: $1.55
eBay: $1.81
They are probably counterfeit. A Windows driver update (AKA "FTDIgate") at one point "bricked" them but I'm ...
- 4,048
4
votes
Accepted
Auto Reset during programming Arduino
A Reset is necessary to activate the Bootloader and allow programming. Without the DTR signal the Reset button has to be pressed just before starting the upload from the Arduino IDE.
- 7,959
4
votes
How do I erase internal EEPROM on a Arduino Pro Mini
You are clearing 28 decimal bytes, but your address range is 28 hex bytes, or 40 bytes of data. Hence, the last 12 characters are untouched.
- 396
4
votes
Accepted
Why is AREF connected to a capacitor in the Arduino Pro Mini Schematic?
On the datasheet for the Atmega328P, in the Analog-to-Digital Converter section, is the sentence:
The voltage reference may be externally decoupled at the AREF pin by a capacitor for better noise ...
- 37.9k
3
votes
Accepted
Newbie - What is the Difference Between Power Supply's GND and Arduino's GND?
I would expect there to be no difference between the grounds in your circuit, and after looking over the schematic for the board, it appears that all of the grounds are common.
I think the most ...
- 1,651
3
votes
Accepted
Flickering LCD when using > 5v power supply on a Pro Mini
If the LCD has a backlight you are absolutely over heating the regulator on that board by running it at 9 or 12V: At 12V with 100mA for the backlight and using 175C/W thermal resistance for the ...
- 407
3
votes
All the differences between Arduinos: Pro Mini & Pro Micro
Arduino Pro Mini
Pin Mapping
Arduino Micro
Pin Mapping
The Arduino page for the Arduino Pro Mini and the Arduino Micro.
Microcontroller
Arduino Pro Mini: ATmega328 (ATmega168 on older boards)
...
- 3,188
3
votes
Most compact method of powering Arduino from wall socket
Try something like this. It's 29x15mm and does 220V AC to 5V/3W DC.
- 131
3
votes
Accepted
What is the best serial protocol for bidirectional communication with NodeMCU?
So you are asking how to use an Arduino Pro Mini as a smart peripheral connected to a NodeMCU master, without making use of the hardware serial port on the latter.
In general, this is either going to ...
- 445
3
votes
Accepted
Need to make an action just once when condition is reached
A possible solution to your problem can be the following:
#include <PCM.h>
const unsigned char sample[] PROGMEM = { //Here goes the sample
};
int low = 0;
int mid = 0;
int high = 0;
bool first =...
- 559
3
votes
Accepted
How to use Arduino Pro Mini without Programmer
You might be on the wrong track.
You do need a crystal (or not, it depends on), and an Atmel programmer if you want to program an empty chip.
However, all Arduino boards come with a chip pre-...
- 771
3
votes
Power Arduino from 230v with battery fallback
This kind of setup lasts around 2-3 days off a single battery.
I measured 15.8 mA consumption on my Pro Mini, running from 9V. A typical 9V battery may have a capacity of 500 mAh, so that is 500 / ...
- 37.9k
3
votes
Accepted
Atmega328p clock and safe operation zone
Just let CKDIV8 set (it just sets system clock prescaler to /8). And you can set different system clock prescaler later.
For changing system clock prescaler you need:
#include <avr/power.h>
...
- 4,742
Only top scored, non community-wiki answers of a minimum length are eligible