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SYNTAX      DIRECT   [<LABEL>] SUBS <dma>
            INDIRECT [<LABEL>] SUBS {ind}[,<next ARP>]

OPERANDS    0 . dma . 127; 0 . next ARP . 7.

EXECUTION   (PC) + 1 . PC
            (ACC) - (dma) . ACC
            Affects OV; affected by OVM.
            Affects C (TMS320C25).
            Not affected by SXM.

DESCRIPTION The contents of the addressed data memory location are
            subtracted from the accumulator with sign-extension
            suppressed. The data is treated as a 16-bit unsigned number,
            regardless of SXM. The accumulator behaves as a signed number.
            SUBS produces the same result as a SUB instruction with SXM
            = 0 and a shift count of 0.

WORDS       1

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

            15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            +-----------------------------------------------+
            |0  1  0  0  0  1  0  1| 1| see indirect fields | INDIRECT
            +-----------------------------------------------+

CYCLES

            +------------------------------------------------+
            |    Cycle Timings for a Single Instruction      |
            |------------------------------------------------|
            | PI/DI | PI/DE | PE/DI | PE/DE  | PR/DI | PR/DE |
            |-------+-------+-------+--------+-------+-------|
      '20   |   1   |  2+d  |  1+p  | 2+d+p  |   -   |   -   |
            |-------+-------+-------+--------+-------+-------|
     'C25   |   1   |  2+d  |  1+p  | 2+d+p  |   1   |  2+d  |
            |------------------------------------------------|
            |    Cycle Timings for a Repeat Instruction      |
            |------------------------------------------------|
      '20   |   n   | 2n+nd |  n+p  | 2n+nd+p|   -   |   -   |
            |-------+-------+-------+--------+-------+-------|
     'C25   |   n   |1+n+nd |  n+p  |1+n+nd+p|   n   |1+n+nd |
            +------------------------------------------------+



EXAMPLE     SUBS  DAT2        (DP = 16)
            or
            SUBS  *           If current auxiliary register contains 2050.

                 BEFORE                 AFTER

            dm2050 >F003         dm2050 >F003
             ACC X >F105          ACC 1  >102
                 C                    C