Assembly - Counting 1's in 16 bit word

I am trying to count the number of 1's in a sixteen bit word for MC68HC12. The only way I can think of is to use 16 BITA instructions, one for each bit location, then increment a counter. I suspect there is a more elegant way to do this. Could someone share their ideas with me.

You can repeatedly AND the number with 1, then right-shift it and do it again.

-Dan

Shift the register through the carry bit, if the carry is set then increment another register
; assembler psuedo code (makes no assumptions about register size)
; if the register are less than 16 bits then you will have to put the test value into the accumulator in to parts or use multiple registers.
; value in to test in A
LD B,0 ; bit counter
LD C,16 ; loop counter
LOOP:
SHLC A ; shift A left through carry
JRNC NOADD
INC B ; count this bit
NOADD:
DEC C ; next bit
JRNZ LOOP