Motorola DSP56000, 24-Bit Digital Signal Processor manual Jump if Bit Set, Example

INSTRUCTION DESCRIPTIONS

JSET

Jump if Bit Set

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

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

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

A JSET instruction cannot be repeated using the REP instruction.

Example:

:

JSET #12,X:<<$FFF2,$4321 ;$4321➞(PC) if bit 12 (SCI COD) is set

:

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

address P:$4321 if bit 12 (SCI COD) of the 16-bit read/write I/O register X:$FFF2 is a one. If the specified bit is not set, no jump is taken and the program counter (PC) is incre- mented 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-135.L — Set if data limiting has occurred. See Notes on page A-135.

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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