The PMC8 keeps track of motor counts on its axes and knows where it is pointed, in those terms. It doesn't know about stars. It may not be obvious at first, but that really is a feature, not a bug.
The astronomical information is back in your control program (CdC, Stellarium, whatever). The driver translates between them. The PMC8's command language is described in the PMC8 Programmers Reference document. This is available either here in the FILES section, or embedded in your ASCOM driver install, if you checked the 'sources' box when you installed.
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras: Nikon D5300, Altair GPCAM2 290M
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer: Thinkpad x230, Win7Pro/64