MC68181 Datasheet, PDF (57/119 Pages) Freescale Semiconductor, Inc – Advance Information ROAMING FLEX chip SIGNAL PROCESSOR

Freescale Semiconductor, Inc.
MC68181
FLEX Message Word Definitions
through d) with the frame and battery cycle explicitly displayed. “Y” and “Z”
indicate non-standard addresses for any-phase and all-phase subscriber units.
• If the subscriber unit contains only a single individual address and the user is
content with the recommended 30 second battery cycle, then the letter “A”,
“E”, or “I” is added as a prefix to the 7-, 9- or 10-digit address, where:
– “A” indicates a single-phase device.
– “E” indicates an any-phase device.
– “I” indicates an all-phase device.
• If the unit were to be a two address unit where both addresses are individual
addresses, then “A”, “E”, or “I” would again preface the address field of the
first address. “B”, “F”, or “J” would preface the second address.
The “B”, “F”, or “J” indicates that the address is a second address and it is to
have the properties of the first address. This rule eliminates the need for an
administrative operator or a salesperson to calculate a starting address, which
would allow standard rules to always apply.
• In other cases, especially where a group address is to be included, it is very
likely that the “U” through “Z” forms of the CAPCODE will be used so that
the frame can be explicitly chosen to provide best battery life, and the
required “same phase” operation can be met in the case of the single-phase
units.
CAPCODE TO BINARY CONVERSION
Short CAPCODE
To convert a short address CAPCODE, the number 32,768 is added to the 7- digit
decimal CAPCODE address (or to any CAPCODE less than 2,031,615). The resultant
number is then converted to a 21-bit binary number, which then becomes the
information bits of the (31,21) BCH code word transmitted over the air.
Long CAPCODE 2,101,249 to 1,075,843,072
Long address set 1–2 is in this range. To convert a long address CAPCODE, the
number 2,068,481 is subtracted from the CAPCODE address. The resultant number is
then divided by 32,768 with the remainder, incremented by 1, being the 1st word of
the long address. This is the same as calculating the ((CAPCODE – 2,068,481) modulo
32768) + 1. This value is converted to a 21-bit binary number, which becomes the
information bits in the (31,21) BCH code word transmitted over the air as the 1st
address word.
The second word of the long address is determined by first calculating the integer
portion of the (CAPCODE – 2,068,481) divided by 32,768. This value is then
subtracted from 2,097,151 (equivalent to the ones complement of the value in binary),
and converted to a 21-bit binary number, which becomes the information bits in the
(31, 21) BCH code word transmitted over the air as the second address word.
MOTOROLA
MC68181 Technical Data Sheet
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