; TMS320C6x assembly language code to perform ordered dithering
; We assume that the thresholds are periodic, and hence, will be
; circularly addressed.  The first two lines set up the modulo
; addressing.  Remove them if the thresholds are in a linear array.
	MVK	.S1 0x0001,AMR	; modulo block size 2^2
	MVKH	.S1 0x4000,AMR	; modulo addr reg B6
; initialize
;   A6 address of pixels
;   B6 address of thresholds
;   B0 number of pixels to threshold
	.trip	100			; minimum loop count
dith:	LDB	.D1 *A6++,A4		; read pixel
||	LDB	.D2 *B6++,B4		; read threshold
||	CMPGTU	.L1x A4,B4,A1		; threshold pixel
||	ZERO	.S1  A5			; 0 if <= threshold
[A1]	MVK	.S1  255,A5		; 255 if > threshold
||	STB	.D1  A5,*A6++		; store result
||[B0]	SUB	.L2  B0,1,B0		; decrement counter
||[B0]	B	.S2  dith		; branch if not zero