cx28560 Mindspeed Technologies, cx28560 Datasheet - Page 252

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

Buffer Controller FIFO Size Calculation
E.1.2
E-2
Assumptions
Figure E-1
Figure E-1. BUFFC Internal FIFO
Overhead bytes contain space reserved for the fragment header, and the space
reserved for last bytes when appropriate.
Y
Data Bytes contain the message data received from the RSLP.
X
N is the number of fragments in the FIFO ready for transmission to the system.
The minimum message size is 40 bytes. Messages that are shorter than this may cause
the buffer to overflow under some conditions (continuous reception of short messages
at line rate is sufficient). This assumption also applies to a stream of aborted
messages.
t
t
is the number of overhead bytes in fragment t.
is the number of data bytes in fragment t.
illustrates the FIFO.
Mindspeed Technologies™
Advance Information
(Initial Bytes)
Fragment N
Fragment 0
Fragment 1
Overhead
Overhead
Overhead
Data
Data
Data
...
CX28560 Data Sheet
28560-DSH-001-B
101302_015