CX28344 Conexant, CX28344 Datasheet - Page 96

• Manufacturer Part Number: CX28344
• Description: (CX2834x) Dual / Triple / Quad / Hex / Octal - Enhanced DS3 / E3 Framer
• Manufacturer: Conexant

Functional Description
Table 2-8. Status Byte Description
2-50
Set
Cleared
Note(s): In (b), the number of data bytes in the block is always 0, as the data bytes are of no significance and therefore discarded
by the RDL. Also, if one or more (a2) blocks is followed by a (b) block, the microprocessor should discard all the data bytes of the
previously-read (a2) blocks, as they belong to the same erroneous/aborted message.
RxGoodBlk
field value
—
Set
Cleared
Undefined
MSB
For type (a1, a2) the RxGoodBlk is set, and for type (b) it is cleared. Refer to
The available RDL-related interrupt events are as follows:
!
!
!
(a1)
(a2)
(b)
FIFO near-full:
" Turned on when the number of bytes in the FIFO buffer is equal to or more
" Turned off when there are no more unread complete blocks left in the FIFO
Message received:
" Turned on when an end-of-message flag sequence or an abort sequence is
" Turned off when the message received status indication is read (unless these
FIFO overrun:
" Turned on when the FIFO buffer is full and another byte has to be written to it.
" Turned off when there are no more unread complete blocks left in the FIFO
Type
than the programmable Near-Full FIFO threshold (range = 2 to 127) [a type
(a2) block ends when this interrupt is turned on, and another block of this type
is not be produced until the interrupt is turned off]
buffer, i.e., when the last byte of the last complete data block has been read (if
after reading all pending complete blocks from the FIFO buffer, the number of
bytes in the remaining incomplete block is again equal to or more than the
threshold, a new interrupt is generated and another type, a2, block terminated)
detected. A type (a1) or (b) block ends when this interrupt is turned on.
interrupts are promptly and consistently read and cleared, this interrupt means
that one or more message received events have occurred since the last read)
A type (b) block (with overrun error-type) ends when this interrupt is turned
on, and another block of this type is not produced until the interrupt is turned
off.
buffer, i.e., when the last byte of the last complete data block has been read
(since all input is discarded by the RDL until the overrun is cleared, this is the
status byte of the incoming message within whose data the overrun error has
occurred).
End of message (detection of flag sequence) with
correct FCS
Partially-received message, FIFO near-full,
message data continue in next block
Errored block cases: end of message with incorrect
FCS, or end of message with number of bits
indivisible by 8 (alignment error), or aborted
message (detection of abort sequence), or overrun
error.
abort, overrun (from low to high). Only one type of
error can be indicated.
Mindspeed Technologies™
Priority of error type is: bad FCS, align error,
Description
Number of data bytes in block
(range = 0 to 127)
Additional Information
CX28342/3/4/6/8 Data Sheet
(Bits 0-6)
—
—
28348-DSH-001-B
Table
2-8.