Internal pull up on I2C bus

[BIBINLUKOSE]

I am using nRF52840-CKAA-R7 II2c to connect to my MSP430 i2c[ slave]. i have put any pullup on the clock and data thinking, to  use nordic pull up in default. clock is connected on P0.06 and data on P0.08. Can some one from nordic tell me, what is the strongest pullup setting i can get using internal pull up. what are my options in that line to have a pullup?

Do we need external pull up to load the bootloader to slave device?

[Dmitry]

Hi,

for 52840,an internal pull-up resistance is in range 11-16 kOhm. The maximum speed depends also on load capacitance of i2c bus components. According to appnote from TI (google by "i2c pull-up resistance"), to achieve reliable communication in standard mode with 16k, load capacitance should not exceed ~70pF. If MSP430 is the only device on the bus and trace length is quite short, everything should work fine. If you need fast mode communication, you should put externall pull-ups anyway.

By the way, MSP430 also has internal pull-ups that could be handy.