SCSI board but no SCSI port

I have a older “key/security” board with SCSI port that I want to use in a computer that has a mainboard with no SCSI ports. Is there anything I can do; is it possible to convert a PCI port to SCSI? Getting a replacement for the SCSI board is not an option, the software it was meant to work with is too old.

** Sorry All, I should have said ISA not SCSI **