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SYNTAX      [<LABEL>] BIOZ <pma>[,{ind}[,<next ARP>]]

OPERANDS    0 . pma . 65535; 0 . next ARP . 7.
               ___
EXECUTION   If BIO = 0:
            then pma . PC; else (PC) + 2 . PC.
            Modify AR(ARP) and ARP as specified.

DESCRIPTION The current auxiliary register and ARP are modified as
            specified, and control passes to the designated program memory
                                 ___
            address (pma) if the BIO pin is low; otherwise, control passes
            to the next instruction. Note that no AR or ARP modification
            occurs if nothing is specified in those fields. Pma can be
            either a symbolic or numeric address.
                                         ___
            BIOZ in conjunction with the BIO pin can be used to test a___
            peripheral is ready to send or receive data.  Polling the BIO
            pin using BIOZ may be preferable to an interrupt when
            executing time-critical loops.

WORDS       2

ENCODING    15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            +-----------------------------------------------+
            |1  1  1  1  1  0  1  0  1| see indirect fields |
            +-----------------------------------------------+
            +-----------------------------------------------+
            |           program memory address              |
            +-----------------------------------------------+

CYCLES

            +----------------------------------------------------+
            |       Cycle Timings for a Single Instruction       |
            |----------------------------------------------------|
            |  PI/DI |  PI/DE |  PE/DI |  PE/DE  | PR/DI | PR/DE |
            |-----------------+------------------+-------+-------|
      '20   |2 (br int-to-int)| 2+p (int-to-ext) |   _   |   _   |
            | 2+p (ext-to-int)| 2+2p (ext-to-ext)|       |       |
            |----------------------------------------------------|
      'C25  | True Conditions:                                   |
            |----------------------------------------------------|
            |              Destination on-chip RAM:              |
            |----------------------------------------------------|
            |    2   |   2    |  2+2p  |  2+2p   |   2   |   2   |
            |----------------------------------------------------|
            |              Destination on-chip ROM:              |
            |----------------------------------------------------|
            |    3   |   3    |  3+2p  |  3+2p   |   3   |   3   |
            |----------------------------------------------------|
            |            Destination external memory:            |
            |----------------------------------------------------|
            |   3+p  |  3+p   |  3+3p  |  3+3p   |  3+p  |  3+p  |
            |----------------------------------------------------|
            |  False Condition:                                  |
            |----------------------------------------------------|
            |               Destination anywhere:                |
            |----------------------------------------------------|
            |    2   |    2   |  2+2p  |  2+2p   |   2   |   2   |
            |----------------------------------------------------|
            |       Cycle Timings for a Repeat Instruction       |
            |----------------------------------------------------|
      '20   |          not repeatable            |   -   |   -   |
            |----------------------------------------------------|
     'C25   |                     not repeatable                 |
            +----------------------------------------------------+



EXAMPLE     BIOZ  PRG64       If the BIO pin is active (low), then a
                              branch to location 64 occurs.