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xxxxh
Address
Space
0778h
4766h
PC
2F03Ah
2F038h
2F036h
2F036h
+04766h
3379Ch
Before:
Address
Space
After:
5092h
2F034h
xxxxh
0778h
4766h
PC
2F03Ah
2F038h
2F036h
5092h
2F034h
xxxxh
5432h
3379Eh
3379Ch
xxxxh
5432h
3379Eh
3379Ch
5432h
+2345h
7777h
src
dst
Sum
xxxxh
2345h
0077Ah
00778h
xxxxh
7777h
0077Ah
00778h
Addressing Modes
4.4.3.3
MSP430X Instruction With Symbolic Mode
When using an MSP430X instruction with Symbolic mode, the operand can be located anywhere in the
range of PC + 19 bits.
Length:
Three or four words
Operation:
The operand address is the sum of the 20-bit PC and the 20-bit index. The 4 MSBs
of the index are contained in the extension word; the 16 LSBs are contained in the
word following the instruction.
Comment:
Valid for source and destination. The assembler calculates the register index and
inserts it.
ADDX.B EDE,TONI ;
Example:
This instruction adds the 8-bit data contained in source byte EDE and destination
byte TONI and places the result into the destination byte TONI.
Source:
Byte EDE located at address 3579Ch, pointed to by PC + 14766h, is the 20-bit
result of 3579Ch – 21036h = 14766h. Address 21036h is the address of the index
in this example.
Destination:
Byte TONI located at address 77778h, pointed to by PC + 56740h, is the 20-bit
result of 77778h – 21038h = 56740h. Address 21038h is the address of the index in
this example.
107
SLAU272C – May 2011 – Revised November 2013
CPUX
Copyright © 2011–2013, Texas Instruments Incorporated