Library /sys$common/syshlp/sysgen.hlb CONNECT, Qualifiers, /CSR  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /CSR=csr-addr

    Specifies the UNIBUS address of the first addressable location on
    the controller (usually the status register) for the device. This
    qualifier must be specified for UNIBUS devices. For devices on
    multiple device boards (for example, the DMF32), the address must
    be the control and status register (CSR) address specified in the
    output of the CONFIGURE command. To specify the address in octal
    or hexadecimal, precede the address with %O or %X, respectively.