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Texas Instruments MSP50C614 User Manual

Page 110

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Instruction Syntax and Addressing Modes

4-18

Example 4.3.20

MOV A3, *R6+0x10

Refer to the initial processor state in Table 4–8 before execution of this instruc-
tion. Load A3 (AC29) with the contents of byte address, R6+0x10. The value
of R6 is unchanged. Final result, AC29=0x0112.

Example 4.3.21

ADD A0~, A0, *R6+0x10, ++A

Refer to the initial processor state in Table 4–8 before execution of this instruc-
tion. Preincrement AP0. After preincrement, A0 is AC3 and A0~ is AC19. Add
AC3 to the contents of byte address R6+0x10 and store the result in AC19. The
value in R6 is unchanged. Final result, AC19 = AC3 + *(R6+0x10) = 0xFEED
+ *0x01FA = 0xFEED + 0x0112 = 0xFFFF.

4.3.6.3

Long Relative

Long relative addressing selects one of the 8 address registers (R

x) as a base

value and adds the value of the second word operand. The base address reg-
ister is not modified.

Syntax:

name [dest,] [src,] *Rx+offset16 [, next A]
name *Rx+offset16 [, src] [, next A]

Address

+

Rx

(x = 0 – 7)

Memory Operand

Operand

Example 4.3.22

MOV A0~, *R1+0x0254, ++A

Refer to the initial processor state in Table 4–8 before execution of this instruc-
tion. Preincrement A0. After preincrement, A0 is AC3 and A0~ is AC19. Load
the contents of the data memory byte location R1+0x0254 into AC19. R1 re-
mains unchanged. Final result, AP0=3, AC19=*(R1+0x0254) = *0x022A =
0x0400.

Example 4.3.23

MOV *R7+0x0442, MR

Refer to the initial processor state in Table 4–8 before execution of this instruc-
tion. Store the value in MR to data memory byte location, R7+0x0442. R7 re-
mains unchanged. Final result, *0x02A1 = 0x1A15.