I am building a quadcopter with my son to teach him and myself the wonders of electronics. I want to get him excited about the subject by creating a dangerous high speed projectile that will keep him interested.
The thing is, I am relatively new as well. I want to get something clear right off the bat. I respect this community greatly and I don't want you to do the project for me. I simply need someone to point me in the right direction. I will learn the proper etiquette and post properly structured information.
As of now I am working with
I will use the multiwii platform.
I can't find a clear wiring diagram for the separate modules. The way I see it is to connect all 3 modules to 3.3vdc and ground then connect all three of their SDA and SCL to A4 and A5 and that's it. They are modules so they include there own pull up resistors??
Let me know if I'm wrong. Push me in the right direction. Help me teach my son to be a fellow electro dork lol.
Data sheets attached
Mpu6050 data sheet won't upload here is the link
HMC5883L_3-Axis_Digital_Compass_IC.pdf (718 KB)
BST-BMP180-DS000-09.pdf (656 KB)
The Nano is a 5V device, right? If so, you will need level shifters between the Nano and the 3.3V devices. I use MOSFET level shifters. Scroll down this page to the bi-directional level shifter using MOSFETS. The 2N7000 is also a good MOSFET for this.
I have a 3.3vdc output on the Arduino nano. Would that be strong enough to power all 3 sensors? I have a 11.1V 1800mAh 65C 3S Lipo Battery powering the Arduino. I have the datasheet for the Arduino attached.
ArduinoNanoManual23.pdf (854 KB)
According to what I can find on the net, the 3.3V output from the FTDI is good for 50mA. Look up the operating currents of the 3.3V devices from their data sheets, add them up and if less than 50mA you are good.
Do you understand that you can't directly connect 3.3V I2C devices to the Nano 5V SDA and SCL pins?
Yes I see that now. The voltage on the communication pins SDA and SCL Is 5v correct? Therefore it may fry the 3.3v sensor modules or not communicate properly.
Lol. I have no mosfets on hand but I do have some transistors and diodes. Let's try that approach and I will report back with a wiring diagram so we can add a "solved" to this. Thank you!
The transistors I have need to high of voltage to switch the signals so I have to try something else...
I just ordered a couple of logic level shifters from SparkFun. Essentially what you suggested but pre-made. I figured why go through the trouble of ordering in parts and making it when it's already done for a couple dollars.
Link to logic level converter. There is a connection diagram there if anyone is interested in making one. Just order it lol.
So if you stumbled across this page and need information on connecting the i2c sensor modules in question, all of your answers will be at the link below thanks to groundfungus. Thanks!
I2C Bi-directional Level Shifter