arduino uno i need another pin.

hi I'm making my project and as time passed by and I figured out my problems I'm missing a pin for 1 of the photodiodes(out of 6).

list of my pins and what I use them for: digital pins: 0,1 I have been told that is used only for Bluetooth and other communications like it, 2,3,4,5,6,7 is for the LCD 8 is for the servo motor 9,10,11 RGB (I'm using only red and green, can I disconnect the blue and the rgb will work?) 12 photodiode1 13 built-in LED (anyway I can use photodiode on this one? ) analog pins: A0 photodiode2 A1 photodiode3 A2 photodiode4 A3 photodiode5 A4,A5 they were supposed to be the number 5 and 6 but apparently my Arduino shield has built-in pullup 3.3k resistors for I2C that I don't even use in my project.(I use 10k resistors with the photodiodes, maybe if I use lower resistors it will work?)

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spycatcher2k:
Just remove the resistors!

they are welded to the shield, I’m new to this and don’t want to ruin it.

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spycatcher2k: Just snip them with a pair of flush cutters :)

I'm pretty sure that if I will do so it will not work at all!

unless you explain why not ofcourse :D

A4,A5 they were supposed to be the number 5 and 6 but apparently my Arduino shield has built-in pullup 3.3k resistors for I2C that I don't even use in my project.(I use 10k resistors with the photodiodes, maybe if I use lower resistors it will work?)

How are you connecting the photodiodes to the other pins?

avr_fred: How are you connecting the photodiodes to the other pins?

I'm connecting all the photo diodes the same way, with a 10k resistor.

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spycatcher2k: The resistors are pull up - removing them will leave the pin connection ready for use.

do you mean that all I need to do is destroy those little pieces of pain and all my problems will go away?

Maybe you should start by explaining why you are using a shield in the first place.

Pieter

PieterP: Maybe you should start by explaining why you are using a shield in the first place.

Pieter

because I got scammed by my school and they took my money for something I don't even need. that's what happens when u make students make a project without any knowledge and make them buy this useless shield

Hi,

What is the '"shield" you have, or is it a UNO controller?

What is your application, what are you trying to do?

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

Can you tell us your electronics, programming, Arduino, hardware experience?

Thanks.. Tom.. :)

9,10,11 RGB (I'm using only red and green, can I disconnect the blue and the rgb will work?)

Yes

0,1 I have been told that is used only for Bluetooth and other communications like it,

Are you using bluetooth or other communications? If not, you can use those pins. Only thing to be aware of is that you might loose the option to upload code at the moment that something is connected to those pins; simple to solve by disconnecting anything that is connected to those pins before you upload. If you use the RX pin for other purposes, you should still be able to use the TX pin for debugging to serial monitor; but I have never tried it.

What else comes in that kit that you have. Something like 74HC595? That will give you 8 outputs at the expense of 3 pins (probably will not help you in this case). Maybe a multiplexer (something like 4052 or 4067).

PS I guess that this relates to https://forum.arduino.cc/index.php?topic=476404.0.

Are you using the shield (that big red piece)? Or are you running without it.

For others: Pictures related to this

TomGeorge: Hi,

What is the '"shield" you have, or is it a UNO controller?

What is your application, what are you trying to do?

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

Can you tell us your electronics, programming, Arduino, hardware experience?

Thanks.. Tom.. :)

I have no idea what shield it is, that's what I got. I'm trying to do a parking lot this is my first project/anything relating to programing or Arduino. my circuit: http://prntscr.com/f7p6yl

sterretje: Yes Are you using bluetooth or other communications? If not, you can use those pins. Only thing to be aware of is that you might loose the option to upload code at the moment that something is connected to those pins; simple to solve by disconnecting anything that is connected to those pins before you upload. If you use the RX pin for other purposes, you should still be able to use the TX pin for debugging to serial monitor; but I have never tried it.

What else comes in that kit that you have. Something like 74HC595? That will give you 8 outputs at the expense of 3 pins (probably will not help you in this case). Maybe a multiplexer (something like 4052 or 4067).

I'm not using any communication (if LCD is communication so yes) I don't really know what is in the kit I just got it because the school made me without telling me anything. Also I don't need the Blue color in the LCD can I use it (digitalpin 11) as another pin?

sterretje: PS I guess that this relates to https://forum.arduino.cc/index.php?topic=476404.0.

Are you using the shield (that big red piece)? Or are you running without it.

For others: Pictures related to this

yes it my Arduino and my post. the Arduino is connected to this red thing.

As I said, if you don’t need blue, you can use that pin for something else.

sterretje: As I said, if you don't need blue, you can use that pin for something else.

I figured out the missing pin problem ( I thought I had to use all 3 colors of rgb to make the rgb work. well seems like I have unknown problem in the code, ill make a new thread for this in programming section. would like you to take a look if you can help