Garbage values on output is mostly due to the baudrate.
Try changing the baudrate on the output terminal to the baudrate in the code.
Try checking the output by changing different baudrates on the terminal.
This must work for you :)
If anyone else is confused by this:
Will it hurt your Arduino?
No, this is a internal voltage reference between VCC & the 1.1v internal analog reference.
Is a voltage divider necessary?
Not unless you have something external of the Arduino to measure!
Is the internal reference actually 1.1v?
No, it seems like each pro mini I have the the 1.1v ...
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 1.1 V reference. This is, however, not what
the code you posted is doing. It is instead measuring the internal
reference against Vcc, as stated in the comment ...
Instead of calling analogRead(), this sketch performs the equivalent actions by directly manipulating the hardware registers to begin a conversion, wait until the conversion is complete, and collect the converted value.
Just reading the final value is accomplished by the statements:
result = ADCL;
result |= ADCH<<8;
All of the statements following ...
Your hookup seems to be correct. However check if there is a capacitor on the pro-mini board between DTR and reset pin, some arduino clones don't come with one.
If there isn't any you can simply connect a capacitor like this:
Reset pin (Arduino Uno) -> Capacitor (0.01uF for example) -> DTR (pro mini). The reason for this hookup is exmplined well here
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 at least) is likely just fine, assuming the linear regulator smoked and failed open, meaning it did NOT pass through the raw input voltage to your ATmega328 mcu....
Wall adapters are not all the same. They can have AC and DC outputs. The DC outputs can be regulated or unregulated. Assuming 1 12V DC wall adapter unregulated you can get maybe 19Vdc from it depending on the design.Always check first, it is much more cost effective then going to the store to buy a new Arduino and what other devices.
Unfortunately, it sounds like it is dead.
I did this early on when I started with arduinos.
In my case I plugged in a "12v 1amp" wall adapter from a linksys router that I didn't check with a DMM to a uno-R3 barrel jack.
The adapter was putting out 22v @ god only knows how many amps. But it had the exact same symptoms I am sorry to say.
I wound up ...
Welcome to ASE.
Communication between the PC and the Arduino Pro Micro happens through the USB, unlike the Arduino Uno and Mega, which use the RX and TX lines.
In your case, the USB pins of the Micro are used to communicate with the PC. Hence, the RX and TX pins are available for digital input and output operations.