I think the 6200 s/w predates the PKTX and so it is likely that no direct driver is available. I don't know the fine details, but the KTX (ISA bus) and the PKTX (PCI bus) have different setup parameters in RSLinx, so they must require different driver s/w.
If your 6200 is up-to-date(5.31 or thereabouts), you can use RSLinx as the driver. Adding RSLinx to the driver list was about the last 'enhancement' made to the 6200 s/w - around 5 yrs ago. This was necessary to enable running the s/w on NT, as none of the direct (DOS) drivers would work on NT. If you're running NT, 2K, or XP, RSLinx is your only option.
I tried it once on NT and it was r..e..a..l..l..y s..l..o..w . . .