Motorola DSP56000, 24-Bit Digital Signal Processor manual Example

INSTRUCTION DESCRIPTIONS

JSSET

Jump to Subroutine if Bit Set

JSSET

nth bit. All address register indirect addressing modes may be used to reference the source operand S. Absolute short and I/O short addressing modes may also be used.

Restrictions: A JSSET instruction used within a DO loop cannot specify the loop address (LA) as its target.

A JSSET located at LA, LA–1, or LA–2 of a DO loop, cannot specify the program control- ler registers SR, SP, SSH, SSL, LA, or LC as its target.

JSSET SSH or JSSET SSL cannot follow an instruction that changes the SP.

A JSSET instruction cannot be repeated using the REP instruction.

Example:

:

JSSET #$17,Y:<$3F,$100 ;go to sub. at P:$0100 if bit 23 in Y:$3F is set

:

Explanation of Example: In this example, program execution is transferred to the sub-

routine at absolute address P:$0100 in program memory if bit 23 of Y memory location

Y:$003F is a one. If the specified bit is not set, no jump is taken and the program counter (PC) is incremented by 1.

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

For destination operand A or B:

S —Computed according to the definition. See Notes on page A-143.L — Set if data limiting has occurred. See Notes on page A-143.

E — Not affected

U — Not affected

N — Not affected

Z — Not affected

V — Not affected

C — Not affected

For other source operands:

The condition codes are not affected.

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