How to attach Receiver/Transmitter to Arduino

Hi
I'm trying to build a RC car with the Arduino Uno and four motors controlled by a
L293D motor shield, I am trying to connect the remote control to the Arduino through a wireless Receiver/Transmitter the problem is that although I don't actually have one yet, from what I'v seen and from common sense I'm pretty sure it will require at least one Arduino pin to plug into but the motor shield uses all the Arduino pins. I'v searched everywhere and I cant find an answer to this.
Thank you so much.

For the sort of remote control you mention I reckon a pair of nRF24L01+ transceivers will work well, be easy to program and be cheap. I use them for model trains.

Have a look at this Simple nRF24L01+ Tutorial.

Wireless problems can be very difficult to debug so get the wireless part working on its own before you start adding any other features.

The examples are as simple as I could make them and they have worked for other Forum members. If you get stuck it will be easier to help with code that I am familiar with. Start by getting the first example to work

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Take another look at your L293D motor shield and consider replacing it with something that uses MOSFETs as its output, this will give you much more power and longer battery life.
Unused digital pins: 2,13. Pin 13 is also connected to the system led. Note the Analog pins A0 ... A5 are still available they not used and yes they can be used as digital pins. Also, I2C (A4 = SDA and A5 = SCL) can be used for I2C I/O etc.
Digital pins: used: 3,4,5,6,7,8,9,10,11,12 however Pin 9 and 10 are only used for the servo motors.
Already in use: 0 (RX) and 1 (TX) for programming etc.
Pin 13 is also connected to the system led.

If I use two nRF24l01+ would I have to have an Arduino at the transmitting end, because I have a very low budget and I don't think I can buy another one, even a nano, at the moment. Also what are Mosfets and how much do they cost?
Thanks.

virtuos1:
If I use two nRF24l01+ would I have to have an Arduino at the transmitting end, because I have a very low budget and I don't think I can buy another one, even a nano, at the moment.

Yes, you would need an Arduino at both ends. But, however you go about it, you will need a transmitter as well as a receiver and Arduino clones are not very expensive.

Also what are Mosfets and how much do they cost?

If the car works with the L298 don't worry about them for now. A Mosfet is a metal oxide semiconductor field effect transistor and they have a much lower ON resistance than the type of transistor used in the L298. That means they don't waste as much energy. In any case, rather than buy individual Mosfets you should consider a replacement motor driver that uses mosfets. If you have a limited budget I would not see that as a high priority. The Pololu website has a range of motor drivers if you want to browse.

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Thank you.

I have two nrf24l01+ modules, but in order to attach them to the Arduino, I will need 3 SPI pins and since the motor driver I am using uses all the Digital pins I only have one SPI pin(10, because I am not using any servos)
I looked into this but I cant find an answer.
Thank you.

virtuos1:
the motor driver I am using uses all the Digital pins I only have one SPI pin

Please post a link to the datasheet for the motor driver.

Using Arduino shields can lead to this sort of problem if the shield designer failed to consider that the user might want to use other boards in addition to the shield. I can't think of any reason why a motor driver shield would have to use pins 11, 12 ad 13

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I dont know how to find a datasheet but here is where I got the motor shield. Also I have a shift register, but I don't know if I can use it for inputs and if they would be SPI pins.
I don't know why but pins 11 and 12 are being used by the shield, I can use 13 but I'll still need one more.

gilshultz:
Digital pins: used: 3,4,5,6,7,8,9,10,11,12 however Pin 9 and 10 are only used for the servo motors.
Already in use: 0 (RX) and 1 (TX) for programming etc.
Pin 13 is also connected to the system led.

I see this in the link you posted

This motor shield is great for controlling a lot of motors of different types. Unfortunately for an arduino uno, it uses up most of the pins so you can't use much in the way of sensors.

I reckon the answer is to get a different motor driver that leaves the SPI pins free for use.

Or perhaps you could use the shield with a Mega which has the SPI pins in a different location

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I don't think I can buy anything at the moment, would it be possible to switch the SPI pins to analog ones?
I looked into this and found a bunch of forums about that, but I don"t know much about Arduino and I didn't really understand anything they were saying. All I need is a piece of code that switches the SPI pins.
Thank you.

I believe it is possible to implement SPI in software but I have never tried it and I have no idea whether it is any good. I presume it would allow the use of any I/O pins. Search for Arduino Software SPI

The hardware SPI only works on pins 11, 12 and 13.

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OK.
Thank you so much, you have been really helpful.