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SYNTAX      [<LABEL>] CNFD

OPERANDS    None

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

DESCRIPTION On-chip RAM block 0 is configured as data memory. The block
            is mapped to locations 512 to 767 in data memory. This
            instruction is the complement of the CNFP instruction and sets
            the CNF bit in status register ST1 to zero. CNF is also loaded
            by the CNFP and LST1 instructions.

            On a 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  0 |
            +-----------------------------------------------+

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     CNFD        A zero is loaded into the CNF status bit, thus
                        configuring block B0 as data memory (see memory
                        maps).