Texas Instruments MSP50C6xx User Manual

Page 99

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Instruction Syntax and Addressing Modes

4-13

Assembly Language Instructions

4.3.3

Immediate Addressing

The address of the memory location is encoded in the instruction word or the
word following the opcode is the immediate value. Single word instructions
take one clock cycle and double word instructions take two clock cycles.

Syntax:

name dest, [src,] imm [, next A]

Where: imm is the immediate value of a 16-bit number.

Example 4.3.1

ADD AP0, 0x1A

Assume the initial processor state in Table 4–8 before execution of this instruc-
tion. This instruction adds the immediate value 0x1A to AP0. Final result AP0
= 0x1A + 2 = 0x1C.

Table 4–8. Initial Processor State for the Examples Before Execution of Instruction

Registers (register# = value)

AP0 = 2

AP1 = 21 (0x15)

AP2 = 11 (0x0B)

AP3 = 29 (0x1D)

R0 = 0x0454

R1 = 0x0200

R2 = 0x0540

R3 = 0x03E2

R4 = 0x0000

R5 = 2

R6 = 0x03E4

R7 = 0x0100

AC2 = 0x13F0

AC1 = 0x0007

AC17 = 0x0112

AC20 = 0x3321

AC3 = 0xFEED

AC28 = 0x11A2

AC29 = 0xAB

AC19 = 0x1200

MR = 0x1A15

data memory (*address = data) [word address; to convert to byte, address multiply by 2]

*0x022A = 0x0400

*0x01F2 = 0x12AC

*0x02A1 = 0x1001

*0x012F = 0x0000

*0x0100 = 0x0ABC

*0x0080 = 0x0000

*0x0001 = 0x499A

*0x01FA = 0x0112

program memory (*address = data)

*0x13F0 = 0x1B12

Example 4.3.2

MOV R5, 0xF000

Loads the immediate value 0xF000 to R5 register. Final result, R5 = 0xF000.

Example 4.3.3

MOVB MR, 0xF2

Loads the immediate byte 0xf2 to MR register. Final result, MR = 0xf2.

Example 4.3.4

AND A0, A0~, 0xFF20, – –A

Assume the initial processor state in Table 4–8 before execution of this instruc-
tion. The source accumulator pointer AP0 is predecremented. After predecre-
ment, A0 points to AC1, and A0~ points to AC17. AC17 is anded with the im-
mediate 16-bit value (0xFF20) and the result is stored in AC1. Final result, AP0
= 1, AC1 = 0xFF20 AND AC17 = 0xFF20 AND 0x0112 = 0x0100.

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