Aha great reading it has no IVS, then i will not buy it.
The spec sheet you linked is wrong
The non -T version has IVS, Fire Detection etc.
https://www.dahuasecurity.com/asset/upload/uploads/soft/20200331/DH-TPC-BF5421-T_Datasheet_20200330.pdf
Wonder if firmware from Non-T can be used
Can...