Re: Arduino Hangs
I would expect what you say to be the case, but it is not what the hardware is doing. I am trying to understand why.
On 8/15/2018 10:40 PM, Tom, wb6b wrote:
The I2C pins are open collector and should be pulled up to 3.3 volts not 5 volts when used with the SI5351. The I2C bus is already pulled up to 3.3V in the uBITX, so additional pull-ups are not needed. The A4 and A5 pins should be programmed as INPUT so they don't overdrive the I2C bus.