Greetings. I am thinking of using the Arduino UNO WiFi Rev 2 in combination with AMG8833 (this is communicated by I2C)
But I have doubts in the use of the I2C of the Arduino UNO WiFi Rev 2 in combination with AMG8833 (this is communicated by I2C)
But I have doubts in the use of the I2C of the Arduino UNO WiFi Rev 2.
What are the pins to use A4 and A5 or SCL and SDA that are next to AREF pin ?.
When viewing the diagram of the Arduino UNO WiFi Rev 2, the SCL and SDA pins are internally connected to the WiFi internally. If these pins are used does not interfere with the use of WiFi?
Thank
SCL and SDA.
I2C is a bus. You can compare it with a street with houses where each house has an (unique) address.
The protocol says to first send a 7-bit address telling a device "hey, there is data coming for you" or "hey, I want some data from you". Only the device whose address matches with the received address will react (accept data or start sending data).
So as long as each device has a unique address (wifi, AMG8833, ...), there will not be a conflict.
On a 328P processor, the processor pins A4 and A5 also carry the I2C signals. On other processors, the I2C signals are not on the same processor pins (e.g. Mega, Leonardo, Uno Wifi). Hence there was a need to have dedicated board pins on the Arduino; those are marked SCL and SDA.
Note:
Be aware that an Uno WiFi Rev2 is not an Uno; 3rd party libraries that directly access processor registers might not 'work'.
PS
changed Uno WiFi to Uno WiFi rev2 after DrAzzy's comment.
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sterretje:
Be aware that an Uno WiFi is not an Uno; 3rd party libraries that directly access processor registers might not 'work'.
The Uno Wifi is an Uno + wifi chip - full library compatibility. Discontinued, but it's just an ESP8266 module and an Uno on the same board, and the same effect can be achieved with an ESP8266 module, 3.3v regulator, and Uno.
The Uno Wifi Rev. 2 is another beast altogether. Much more capable chip, but very different from traditional AVRs, and very new; lots of libraries don't support it, and hardly anyone on these forums knows jack about it.
The fact that they named the Uno Wifi Rev. 2 something with the word "uno" in the name is an example of the typical cluelessness of the Arduino team w/regards to what will confuse new users (other examples: Selling an "Arduino Due" and "Arduino Duemillanove" in countries that don't speak italian, where people would assume the former was an abbreviation for the latter. Calling pins that work with analogRead "analog pins", which every newbie assumes means they can't do digital I/O)
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Thank you. I just spent 6 hours trying to figure this out.
Why the (expletive deleted) is this thing called Arduino UNO WiFi Rev2 when it's not compatible with the Arduino UNO? I thought that was implicit. So I wasted a lot of money and a lot of time for nothing.
Thank's Drazzy ... you saved me another 12 hours debugging code and reading spec sheets.
Sorry but this is just horse (expletive deleted) from Arduino.