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SYNTAX      [<LABEL>] SSXM

OPERANDS    None

EXECUTION   (PC) + 1 . PC
            1 . SXM status bit in status register ST1
            Affects SXM.

DESCRIPTION The SSXM instruction sets the SXM status bit to logic one
            which enables sign-extension on shifted data memory values for
            the following arithmetic instructions: ADD, ADDT, ADLK, LAC,
            LACT, LALK, SBLK, SUB, and SUBT.

            SSXM also affects the definition of the SFR instruction. SXM
            may also be loaded by the LST1 and RSXM instructions.

WORDS       1

ENCODING    15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            +-----------------------------------------------+
            |1  1  0  0  1  1  1  0  0  0  0  0  0  1  1  1 |
            +-----------------------------------------------+

CYCLES

            +------------------------------------------------+
            |    Cycle Timings for a Single Instruction      |
            |------------------------------------------------|
            | PI/DI | PI/DE | PE/DI | PE/DE  | PR/DI | PR/DE |
            |-------+-------+-------+--------+-------+-------|
      '20   |   1   |   1   |  1+p  |  1+p   |   -   |   -   |
            |-------+-------+-------+--------+-------+-------|
     'C25   |   1   |   1   |  1+p  |  1+p   |   1   |   1   |
            |------------------------------------------------|
            |    Cycle Timings for a Repeat Instruction      |
            |------------------------------------------------|
      '20   |   n   |   n   |  n+p  |  n+p   |   -   |   -   |
            |-------+-------+-------+--------+-------+-------|
     'C25   |   n   |   n   |  n+p  |  n+p   |   n   |   n   |
            +------------------------------------------------+



EXAMPLE     SSXM              SXM is set, enabling sign-extension on
                              subsequent instructions.