MCIMX6SLEVK, what is the function of the AC14 pin (REF_CLK_24M) connection between the processor and the PF0100 (INTB)?

[RobertCorrellus]

MCIMX6SLEVK,  what is the function of the AC14 pin (REF_CLK_24M) connection between the processor and the PF0100 (INTB)?

[PeterChan · Accepted solution]

Pin INTB is the open drain interrupt signal from PF0100 to processor. On EVK, this pin is connecting to REF_CLK_24M which is selected as GPIO input GPIO3_IO21 by default.

[RobertCorrellus]

Thanks for your quick reply.  The interrupt from the PF0100 is open drain to the processor, should there be a pull-up on the line?

[PeterChan]

It is optional to have external pull-up on the line because the pad REF_CLK_24M has internal pull-up which can be configured in the IOMUXC_SW_PAD_CTL_PAD_REF_CLK_24M register.