cx28560 Mindspeed Technologies, cx28560 Datasheet - Page 221

• Manufacturer Part Number: cx28560
• Description: Hdlc Controller
• Manufacturer: Mindspeed Technologies

CX28560 Data Sheet
B.3.2
28560-DSH-001-B
Harmonic Bit Rates
To calculate the number of clocks between services necessary for the group (as
calculated for the highest bit rate for the group), the following is considered.
The slots allocated per channel will be separated by a standard step size for each
group. The standard step size is calculated according to the channel’s bit rate and the
minimum number of accumulated bytes of data that will require servicing (average).
The main inefficiency in the above division of bit rates is that a channel just above
one of the limits is considered as a channel with double its actual bit rate. This can be
avoided if harmonics are introduced. The harmonic method treats the mid-bit rate
between the limits as a new boundary. Those channels that fall between the lower
limit and the mid-range limit are assigned to the group below and the group below
that (thus treating it as a channel of bit rate of the mid-range value). The channels
within the groups are treated the same regardless of whether they were assigned to
that group due to being in the upper half of the group’s limits, or due to being in the
lower half of the group above.
Mindspeed Technologies™
Advance Information
Flexiframe Algorithm
B
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