Arduino Nano Not Recognized by Computers

Hello,

I have been using a Nano to display pressure and temperature sensor values to an OLED i2c display. I have had the board for a month or two and I have not encountered any problems. After changing a pull up resistor however, the board was no longer recognized by my laptop. I could not select a serial port, and the device did not show up in device manager. It also did not show up on several other computers and using several different USB cords. The board's led still lights up when given power from the USB, but could some other part of the board be fried? The problem happened after soldering a resistor from analog pin 0 to +5v, and I don't think I accidentally shorted something/removed a connection with the soldering iron. I also do not think I have supplied over voltage to anything on the board either, because I have only used a USB and 3 AA batteries in series to power it.

I looked on this forum for people with similar problems where the board was not recognized by the computer, but their issues mostly happened on one computer or when they first attempted to power up their boards. I have tried to update the drivers to see if that might fix the issue, but it always says they are up to date.

I am still not sure if this is a problem with software or the board itself. Any thoughts?

Can you give us more information what you have been trying to do with analog pin 0 what is the value of pull up resistor and you also said you used usb and 3 AA batteries in series did you use them on the USB port of the DC jack?

I have the temperature sensor wired to analog pin 0, 5v, and Gnd. The sensor values do not stay "steady", so I was thinking that a pull up resistor might fix those values (The same thing I did for the pressure sensor). The 10k resistor didn't work, the sensor just read the value of voltage drop across the pull up, not the actual sensor data. I am novice with pull up resistors, and some people said I should have a pull down resistor for the tmp sensor instead, but that also didn't work. I thought that if I increased the pull up resistance the sensor values might be displayed correctly, so I changed it to a 100k ohm resistor. After that the board did not show up.

What I meant about the powering of the board was: I used the USB power when testing the code, but for my final project I want it to run off its own power source. I did not put the AA batteries and USB power in series, I alternated between the two sources. I applied ~5v to Vin with the 3 AA batteries.

I thought I may have shorted the board by testing the pull down resistor that went from 5v to Gnd, but the resistance should have stopped that from happening.