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SYNTAX      [<LABEL>] LACK <constant>

OPERANDS    0 . constant . 255

EXECUTION   (PC) + 1 . PC
            8-bit positive constant . ACC
            Not affected by SXM.

DESCRIPTION The 8-bit constant is loaded into the accumulator right-
            justified. The upper 24 bits of the accumulator are zeroed
            (i.e. sign extension is suppressed).

WORDS       1

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

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   |       not repeatable            |   -   |   -   |
            |-------------------------------------------------|
     'C25   |                  not repeatable                 |
            +-------------------------------------------------+



EXAMPLE     LACK  >15

                     BEFORE       AFTER

                  ACC X >31   ACC X >15
                      C           C