MIOS8: How fast is the IIC clock (with/without clock streching)?

[Rio]

Simple question for the core v3 /PIC18F board using MIOS8:

How fast is the SC line for both modes (MIOS_IIC_CtrlSet [0 default / 1 clock stretching]) ? and is it <400KHz? Because one of my external boards as an IIC slave only accepts a clock up to 400KHz and it does not react as it should ATM.

It seems that I get an ACK back to the PIC18F master in clock stretching mode, but the external device itself remains without any functionality. If I try it without clock stretching, the watchdog restarts the PIC18F master app because it does not receive an ACK in the loop and the loop probably runs too long for that.

BTW: the external board can be well controlled by an Arduino using the standard frequency of 100Khz defined in the wire/twi classes of the Arduino core library:https://github.com/arduino/ArduinoCore-avr/blob/master/libraries/Wire/src/utility/twi.h#L30

But of course I don't want to control it with an Arduino, but with my PIC18F with MIOS8!

Edited August 13 by Rio
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