The STM6905 datasheet says in Table 2 that there is an internal 10k pull-up on RST#, which seems wrong since that's an open-drain output. Then in Section 2.6 and in Section 3 it says that an external pull-up to VCC should be used.
Welcome
The STM6905 was launched in 2007. The data sheet was last updated in 2014 – but nobody had actually spotted the typo until now! Thank you for your keen observation and for bringing this to our attention!
But to summarise once again: there is a pull-up resistor only on the /MR input, but not on the /RST open-drain output.
Regards
/Peter
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