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SYNTAX      DIRECT   [<LABEL>] LST1 <dma>
            INDIRECT [<LABEL>] LST1 {ind}[,<next ARP>]

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

EXECUTION   (PC) + 1 . PC
            (dma) . status register ST1
            Affects ARP, ARB, CNF, TC, SXM, XF, FO, TXM, and PM.
            Affects C, HM, and FSM (TMS320C25).

DESCRIPTION Status register ST1 is loaded with the data memory  value. the
            bits of the data memory value, which are loaded into the ARB,
            are also loaded into the ARP to facilitate context switching.
            Note that if a next ARP is specified via the indirect
            addressing mode, the specified value is ignored.

            LST1 is used to load status bits after interrupts and
            subroutine calls. ST1 contains the status bits: ARB (auxiliary
            register pointer buffer), CNF (RAM configuration control) bit,
            TC (test/control) bit, SXM (sign-extension mode) bit, XF
            (external flag) bit, FO (serial port format) bit, TXM
            (transmit mode) bit, and the PM (product register shift mode)
            bit. ST1 on the TMS320C25 also contains the status bits: C
            (carry) bit, HM (hold mode) bit, and FSM (frame
            synchronization mode) bit. On the TMS32020, bits 5, 6, and 9
            are one's. The bits loaded into status register ST1 from the
            data memory word are as follows:

               15 14 13  12 11  10  9  8  7  6   5  4  3   2  1  0
               +---------------------------------------------------+
               |  ARB  |CNF|TC|SXM| C| 1  1|HM|FSM|XF|FO|TXM|  PM  |
               +---------------------------------------------------+
            On the TMS32020, bits 5, 6, and 9 are one's.

WORDS       1

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



EXAMPLE     LARP  3
            LST1  *-          The data memory word addressed by the
                              contents of auxiliary register AR3 replaces
                              the status bits of status register ST1, and
                              AR3 is decremented.


EXAMPLE     LST1  >61         (DP = 0)

                BEFORE             AFTER

            dm97 >0580        dm97 >0580
             ST0 >AC00         ST0 >0C00
             ST1 >0581         ST1 >0580


EXAMPLE     LARP  AR4         (AR4 = >3FE)
            LST1  *-

                BEFORE             AFTER

             AR4  >3FE         AR4  >3FD
          dm1022 >4F90      dm1022 >4F90
             ST0 >FC04         ST0 >5C04
             ST1 >E780         ST1 >4F90


EXAMPLE     LARP  AR4         (AR4 = >3FE)
            LST   *-,1

                BEFORE             AFTER

             AR4  >3FE         AR4  >3FD
          dm1022 >6190      dm1023 >6190
             ST0 >FE04         ST0 >7E04
             ST1 >0593         ST1 >6190