Leonard,
There are lots of ways to do this as Jeff suggested.

D(1)=ROTATE/ZAXIS,90
D(2)=TRANS/XORIG,500,YORIG,500,ZORIG-500

or...

F(PL)=FEAT/PLANE...
F(LN)=FEAT/LINE....
F(PT)=FEAT/POINT...
DATDEF/DAT(A),F(PL)
DATDEF/DAT(B),F(LN)
DATDEF/DAT(C),F(PT)
D(PCS)=DATSET/DAT(A),ZDIR,ZORIG,DAT(B),XDIR,YORIG,DAT(C),XORIG

or....

D(PCS)=DATSET/TRMATX.......

Here you can define the xyz and transformation matrix in one go. Don't know of many systems that support this.

Regards
Keith Morton