Motorola DSP56000, 24-Bit Digital Signal Processor manual Long Memory Data Move, CMP Y0,B

INSTRUCTION DESCRIPTIONS

	L:	Long Memory Data Move		L:
Example:
:
	CMP Y0,B	A,L:$1234	;compare Y0 and B, save 48-bit A1:A0 value
:

A

Before Execution

$01:234567:89ABCD

A

After Execution

$01:234567:89ABCD

X:$1234

$000000

X:$1234

$7FFFFF

Y:$1234

$:000000

Y:$1234

$FFFFFF

Explanation of Example: Prior to execution, the 56-bit A accumulator contains the

value $01:234567:89ABCD, the 24-bit X memory location X:$1234 contains the value

$000000, and the 24-bit Y memory location Y:$1234 contains the value $000000. The

execution of the parallel move portion of the instruction, A,L:$1234, moves the 48-bit lim- ited positive saturation constant $7FFFFF:FFFFFF into the specified long memory loca- tion by moving the MS 24 bits of the 48-bit limited positive saturation constant ($7FFFFF) into the 24-bit X memory location X:$1234 and by moving the LS 24 bits of the 48-bit lim- ited positive saturation constant ($FFFFFF) into the 24-bit Y memory location Y:$1234 since the signed integer portion of the A accumulator was in use.

Condition Codes:

15	14	13	12	11		10	9		8	7	6	5	4	3	2	1		0
LF	DM	T	**		S1	S0		I1	I0	S	L	E	U	N	Z		V	C
				MR									CCR

S — Computed according to the definition in A.5 CONDITION CODE COMPUTATION L — Set if data limiting has occurred during parallel move.

Note: The MOVE A,L:ea operation will result in a 48-bit positive or negative saturation constant being stored in the specified 24-bit X and Y memory locations if the signed inte- ger portion of the A accumulator is in use. The MOVE AB,L:ea operation will result in either one or two 24-bit positive and/or negative saturation constant(s) being stored in the specified 24-bit X and/or Y memory location(s) if the signed integer portion of the A and/ or B accumulator(s) is in use.

MOTOROLA INSTRUCTION SET DETAILS A - 199