VMS Help MACRO, VAX MACRO Assembler, Instructions, MOVP  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Purpose:        Moved a packed decimal string from one memory
                    location to another
    Format:         opcode len.rw,srcaddr.ab,dstaddr.ab
    Operation:      ({dstaddr + ZEXT (len/2)} : dstaddr) =
                    ({srcaddr + ZEXT (len/2)} : srcaddr)
    C. Codes:       N = {{dst string} LSS 0}, V = 0,
                    Z = {{dst string} EQL 0}, C = C
    Exceptions:     Reserved operand
    Opcodes:        34    MOVP     Move packed
    Description:    The string dst specified by dstaddr and len is
                    replaced by the string src specified by srcaddr
                    and len.
    Notes:          After execution:

                    R0 = 0
                    R1 = address of the byte containing the
                         most-significant digit of the source string
                    R2 = 0
                    R3 = address of the byte containing the
                         most-significant digit of the destination string