Texas Instruments MSP430x1xx manual Jumps, 13.Jump Instructions, Mnemonic Reg, D-Reg Operation

Instruction Set

3.4.3Jumps

Figure 3−11 shows the conditional-jump instruction format.

Figure 3−11. Jump Instruction Format

15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
	Op-code			C						10-Bit PC Offset

Table 3−13 lists and describes the jump instructions.

Table 3−13.Jump Instructions

Mnemonic	S-Reg, D-Reg	Operation
JEQ/JZ	Label	Jump to label if zero bit is set
JNE/JNZ	Label	Jump to label if zero bit is reset
JC	Label	Jump to label if carry bit is set
JNC	Label	Jump to label if carry bit is reset
JN	Label	Jump to label if negative bit is set
JGE	Label	Jump to label if (N .XOR. V) = 0
JL	Label	Jump to label if (N .XOR. V) = 1
JMP	Label	Jump to label unconditionally

Conditional jumps support program branching relative to the PC and do not affect the status bits. The possible jump range is from − 511 to +512 words relative to the PC value at the jump instruction. The 10-bit program-counter offset is treated as a signed 10-bit value that is doubled and added to the program counter:

PCnew = PCold + 2 + PCoffset ⋅ 2

3-20RISC 16-Bit CPU