Atmel START ASF "I2C baudrate too low"

Go To Last Post
2 posts / 0 new
Author
Message
#1
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Sorry if this is the wrong forum but I don't see a forum for the Atmel START.

 

Using Atmel START and Atmel Studio 7 to create an I2C project for the ATSAMD21G18 (Adafruit Feather M0). I created a simple project with only Delay and I2C drivers selected on START. When I build the resultant project in Studio (without ANY modifications) I get a warning "Requested I2C baudrate too low, please check". I had selected the speed at 400KHz in START. The resulting speed is verrrrry slow! Using i2c_m_sync_set_baudrate to change the speed (after disabling the hardware and re-enabling) seems to have no effect.

 

Please help!

 

Thanks.

Sehnsucht

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

It might be you have the default clock setup which is OSC8M with prescaler /8  (so 1 MHz) which is too low to get 400 KHz for I2C. If this is the case change the clock setup (might be ok just changing the OSC8M prescaler from /8 to /1).

/Lars