Calculates the number of bits set to "1" in address contained in
Rs0 and puts the result in Rd3 according to BS (bank select).
Instruction is stack conditioned.
Takes 5 cycles to execute.
Example: IBITCOUNT A3 3 A0
MPC BS3 C3 P3 P0
------------------
IBNC 0 0 00 A0
- 0 0 00 00
- 0 0 00 00
- 0 0 00 00
- 3 0 A3 00
No exceptions.
IBITCOUNT 0x21 3 0x20 !! Calculate the number of bits set
!! to "1" in content of register 0x20
!! and put the result in register 0x21