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SYNTAX      [<LABEL>] CNFP

OPERANDS    None

EXECUTION   (PC) + 1 . PC
            1 . RAM configuration control (CNF) status bit
            Affects CNF.

DESCRIPTION On-chip RAM block 0 is configured as program memory. The block
            is mapped to locations 65280 to 65535 in program memory space.
            This instruction is the complement of the CNFD instruction and
            sets the CNF bit in status register ST1 to one. CNF is also
            loaded by the CNFP and LST1 instructions.

            Configuring this block as program memory allows the use of the
            program counter as an address generator to access data from
            on-chip RAM. Used in conjunction with the repeat instructions,
            this allows two data memory locations to be addressed
            simultaneously, one from the auxiliary registers and one from
            the program counter. Instructions that take advantage of this
            feature are the MAC, MACD, BLKD, and BLKP.

            On the TMS32020, the instruction fetch immediately following
            a CNFD or CNFP instruction uses the old CNF value, even if it
            is the fetch of the second word of a two-word instruction.

            On a TMS320C25, the next two instruction fetches immediately
            following a CNFD or CNFP instruction use the old value of the
            CNF.

WORDS       1

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

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   |   n   |   n   |  n+p  |  n+p   |   -   |   -   |
            |-------+-------+-------+--------+-------+-------|
     'C25   |   n   |   n   |  n+p  |  n+p   |   n   |   n   |
            +------------------------------------------------+



EXAMPLE     CNFP        The CNF bit is set to logic 1, thus configuring
                        block B0 as program memory (see memory maps).