6803 registers

[Clendening Chad]

Does anybody have an explanation of the control registers between 17 and
1f for the MC6803U4 or mc6801u4?  I need 17( timer control reg 1)
		 	     		   18( timer control reg 2)
			    		   19( timer status reg)

I would also like to know if anyone has any information on the 
motorola SC87313CP, a 40 pin DIP, somewhat functionally similiar to a 6821
but the pinout and operation is differant.  It has only 16 registers

This is out of an '85 chrysler EFI logic unit.  The later ecu's used an
RCA # 9479 or $8545.  This is the same chip.


Chad