nRF5340 conflicting documentation on I2C (aka TWI/TWIM)

[hmolesworth]

The nRF5340 has a special setting for high-drive open-drain I2C/TWI/TWIM: namely E0E1; specifically E0E1 for I2C which only applies to pins P1.02 and P1.03, as E0E1 applies with different meaning for other port pins.

The port CNF description in the product description, presumably for P0, "- 7.13.5.11 PIN_CNF[n] (n=0..31) (Retained)" - is somewhat conflicting on this point: "E0E1 11 Extra high drive '0', extra high drive '1'"). However there is no PIN_CNF[n] (n=0..15) specification for P1. Does open-drain only apply to the pins P1.02 and P1.03? Why is there no P1 specification?

Regarding the nRF5340 DK on the use of these I2C pins:
The I2C/TWI/TWIM pins are not just connected to the user nRF5340 but also to the interface nRF5340; we have no idea what that does and no way to isolate these pins from the interface nRF5340. Does the Interface nRF5340 impact operation on the I2C in any way?

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User nRF5340 U1 Interface nRF5340 U2 Arduino Board On-board Pull-ups Connectors

====================== ==================== ======================== ======================== =================================

U1 P1.02 AE1 P1.02/I2C U2 P1.02 AE1 via 0R0 R20 to P1.02 SDA R48 4k7 PU via U6 switch P10 pin 9 P4 pin 9 P16 pin 18

U1 P1.03 AF2 P1.03/I2C U2 P1.03 AF2 via 0R0 R24 to P1.03 SCL R49 4k7 PU via U6 switch P10 pin 10 P4 pin 10 P16 pin 20

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

User nRF5340 U1        Interface nRF5340 U2 Arduino Board            On-board Pull-ups        Connectors
====================== ==================== ======================== ======================== =================================
U1 P1.02 AE1 P1.02/I2C U2 P1.02 AE1         via 0R0 R20 to P1.02 SDA R48 4k7 PU via U6 switch P10 pin  9  P4 pin  9  P16 pin 18
U1 P1.03 AF2 P1.03/I2C U2 P1.03 AF2         via 0R0 R24 to P1.03 SCL R49 4k7 PU via U6 switch P10 pin 10  P4 pin 10  P16 pin 20

This query is consequential to ticket issue-with-i2c-communication-in-with-multiple-i2c-sensors raised by frax. Development environment is not a factor.