Cheap trackers for OpenHayStack

[sonictruth]

Hi,

I bought two cheap trackers from Ali.
The first one has a chip marked as RM1200 and pads labeled RX, TX, and GND exposed (maybe it's a serial interface).

Second is marked as ST17H65B and pads labeled as P9 P10

My question is whether any of these trackers are usable with OpenHaystack. I can't find anything about the RM1200. For the Lanze one, I found the Biemster firmware, but it's for the ST17H66. Would it work on the ST17H65B? Can I use the P9 and P10 to write the firmware? I can't find any details.

Thank you.

[fz6]

https://github.com/pix/heystack-nrf5x

Has Ali links for trackers with firmware

[Systm21]

biemster/FindMy#74

This should help you, there are experts, that have a lot of knowledge.

Somewhere i read, that the st17h65B can be flashed like the 66B.