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SYNTAX      [<LABEL>] ANDK <constant>[,shift>]

OPERANDS    16-bit constant; 0 . shift . 15 (defaults to 0).

EXECUTION   (PC) + 2 . PC
            (ACC(30-0)).AND.[(constant * 2 ^shift)] . ACC(30-0)
            0 . ACC(31) and all other bit positions unnoccupied by the
            shifted constant.
            Not affected by SXM.

DESCRIPTION The 16-bit immediate constant is left shifted as specified
            and AND'ed with the accumulator. Low-order bits below and the
            high-oreder bits above the shifted value are treated as
            zeroes, clearing the corresponding bits in the accumulator.
            Note that the accumulator's most significant bit is always
            zeroed regardless of the shift-code value.

WORDS       2

ENCODING    15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            +-----------------------------------------------+
            |1  1  0  1|   shift   | 0  0  0  0  0  1  0  0 |
            +-----------------------------------------------+
            +-----------------------------------------------+
            |               16-bit constant                 |
            +-----------------------------------------------+

CYCLES

            +------------------------------------------------+
            |    Cycle Timings for a Single Instruction      |
            |------------------------------------------------|
            | PI/DI | PI/DE | PE/DI | PE/DE  | PR/DI | PR/DE |
            |-------+-------+-------+--------+-------+-------|
      '20   |   2   |   2   | 2+2p  |  2+2p  |   -   |   -   |
            |-------+-------+-------+--------+-------+-------|
     'C25   |   2   |   2   | 2+2p  |  2+2p  |   2   |   2   |
            |------------------------------------------------|
            |    Cycle Timings for a Repeat Instruction      |
      '20   |------------------------------------------------|
     'C25   |                not repeatable                  |
            +------------------------------------------------+



EXAMPLE     ANDK  >FFFF,12

                 BEFORE              AFTER

        ACC X >12345678    ACC X >02345000
            C                  C