documentation for readnvram/writenvram read/write to buffer missing the max. buffer size

[MaDill]

• Arduino board: UNO

• Arduino IDE version (found in Arduino -> About Arduino menu): Arduino IDE 1.8.9 or VS Studio Code 1.74.3 with PlatformIO 2.5.5, both with RTClib 2.1.1

• List the steps to reproduce the problem below:

I use the example from the Arduino IDE and modified it. In the beginning I tried to read/write the whole nvram into/from a buffer. It does not fit by read byte by byte. It fit roughly be some bytes was inserted or missing. I did not receive an error or some other hint.

After some searching I found a comment in the Adafruit BusIO > Adafruit_I2CDevice.cpp:
// currently not guaranteed to work if more than 32 bytes! // we will need to find out if some platforms have larger // I2C buffer sizes :/

Maybe this can be added to the documentation.

Here is my scetch.

ds1307nvram.ino.txt