The 32 Khz onboard oscillator has special bias conditions that make it
a non CMOS compatible input if I am not mistaken. So consider filing a
CASE and asking that, as well as can you AC couple to the xtal input side
pin an external 32 Khz source, that might work. Post the answer back here
for the benefit of the forum.
To create a technical or issue case at Cypress -
“Create a Case”
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