; +++++++++++ This returns the square root of E (rounded down).
;===============================================================
sqrtE:
;===============================================================
;Input:
;     E is the value to find the square root of
;Outputs:
;     A is E-D^2
;     B is 0
;     D is the result
;     E is not changed
;     HL is not changed
;Destroys:
;     C=2D+1 if D is even, 2D-1 if D is odd

	xor	a		;1      4         4
	ld	d,a		;1      4         4
	ld	c,a		;1      4         4
	ld	b,4		;2      7         7
sqrtELoop:
	rlc	d		;2      8        32
	ld	c,d		;1      4        16
	scf			;1      4        16
	rl	c		;2      8        32
	rlc	e		;2      8        32
	rla			;1      4        16
	rlc	e		;2      8        32
	rla			;1      4        16
	cp	c		;1      4        16
	jr	c,sqrtEskp	;4    12|15      48+3x
	inc	d		;--    --        --
	sub	c		;--    --        --
sqrtEskp:
	djnz	sqrtELoop	;2    13|8       47
	ret			;1     10        10
;===============================================================
;Size  : 25 bytes
;Speed : 332+3x cycles
;   x is the number of set bits in the result. This will not
;   exceed 4, so the range for cycles is 332 to 344. To put this
;   into perspective, under the slowest conditions (4 set bits
;   in the result at 6MHz), this can execute over 18000 times
;   in a second.
;===============================================================

	end