X-Hacker.org- TMS320C2x DSP - syntax direct [<label>] lta <dma>

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

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

EXECUTION   (PC) + 1 . PC
            (dma) . T register
            (ACC) + (shifted P register) . ACC

            Affects OV; affected by OVM and PM.
            Affects C (TMS320C25).

DESCRIPTION The T register is loaded with the contents of the specified
            data memory address (dma). The contents of the product
            register, shifted as defined by the PM status bits, are added
            to the accumulator, with the result left in the accumulator.

            The function of the LTA instruction is included in the LTD
            instruction.

WORDS       1

ENCODING    15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            +-----------------------------------------------+
            |0  0  1  1  1  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  0  1  1  1  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     LTA   DAT36       (DP = 6, PM = 0)
            or
            LTA   *           If current auxiliary register contains 804.

               BEFORE             AFTER

            dm804 >62         dm804 >62
                T  >3             T >62
                P  >F             P  >F
            ACC X  >5         ACC X >14
                C                 C

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