Retrieves the version number of the VPOWERD device.
Clears the carry flag and returns a non-zero value if the VPOWERD device is loaded. The low-order word of the return value contains the VPOWERD version. The high-order byte contains the major version number and the low-order byte contains the minor version number.
For example, the function returns 0x400 for version 4.0 of the VPOWER device.