Hello, Since my last post lead me to work with I2C, I am very curious to know about it’s limitations and have a couple questions/scenarios that I’d like to understand if anyone can shed some light on them I’d really appreciate it :slight_smile: I know that Wire.write can read a string, such as: …

Hi @UST Your first question about why Wire.write(“a string of chars”); works but it does not work with String objects is pretty easy. First off, in Arduino land, print methods are for user-readable string data and write methods are for binary data that is not generally user-readable. This is impo…

As for the 32byte limit. The reason for this might be that in spark_wiring_i2c.h the BUFFER_LENGTH is defined as 32. So even if you request more than 32 bytes, the length will be clipped to 32 and Wire.read() will not actually request more bytes, since it doesn’t actually do any I2C communication …

Thanks for the reply @bko ! Okay the reason for number one makes sense thanks for clearing that up! I'm using I2C because it was a suggested alternate solution to a problem I had from a previous post: [image] Two Cores, One SD Hardware …

@UST , if I recall in that other post, I suggested I2C or Serial. Using serial would give you a much more flexible solution for your data transfer since Serial is a stream and simple to work with. You wifi Core would send a request to your logging core and then listen for and assemble the data to …

Oh man :frowning: That is exactly what I need … and yes @peekay123 you did suggest both , sorry bout that! But I understood the Serial route as making user defined commands that you call through a Serial terminal? Okay I have some major digging to do, but glad that I learned I2C (to some extent) an…

@UST , you can start with the ArduinoSerialCommand link I provided in the other thread and maybe look at this topic for some ideas: [image] Arduino serial communication to Spark Core I followed this tutorial here in hopes of establishing serial communication between an Arduino Uno and Spar…

Thanks @peekay123 appreciate it 10fold!

@UST , I agree, serial should be the way to go for you, but as I got the impression that you are still at the beginning of your journey with the Core and C and serial communication, I’d suggest you just do some very basic serial communication to get the grip on what’s going on at the basic level, bef…

You’re a champ @ScruffR thanks a lot for the message. As I am new to all the things you said, I felt I had an understanding of Serial comm so I just tried shoving in what I thought would work into my current project and got 90% of the way there. Spent hours getting frustrated because things were no…

In The Interest of I2C

Firmware

peekay123 January 9, 2015, 3:44pm 7

@UST, you can start with the ArduinoSerialCommand link I provided in the other thread and maybe look at this topic for some ideas:

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In The Interest of I2C

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