IBM3009K2672
IBM SONET/SDH Framer
Each receive Telecom Bus port has an 8-bit wide data bus that outputs the STM-1/STS-3c # data from the
622.08 Mb/s or 155.52 Mb/s line input to receive Telecom Bus #. The receive Telecom Bus data is byte-
aligned and the entire payload, including TOH and POH, is passed through the SONET/SDH framer.
When processing an STM-4c/STS-12c, the four receive Telecom Buses act as a single Telecom Bus, where
RXTB1DATA(7) is the MSB and is the first bit received, while RXTB4DATA(0) is the LSB and is the last bit
received.
The receive Telecom Bus C1J1 output (RXTB#C1J1) can be programmed to provide two different types of
indications, on a per Telecom Bus basis, depending on the setting of the CPOS control bits in the OR#Conf13
registers. When CPOS is set to ‘1’, the corresponding RXTB#C1J1 signal provides two pulses. One pulse is
coincident with the C11 byte (RXTB#C1J1 is high and RXTB#SPE is low) and the other is coincident with the
J1 byte (RXTB#C1J1 is high and RXTB#SPE is high). The J1 pulse will track the J1 byte position as the
SONET/SDH framer receives pointer adjustments. When CPOS is set to ’0’, the J1 pulse is eliminated and
the C1 pulse is coincident with the A2 byte.
3
For all subframes, the receive Telecom Bus SPE output (RXTB#SPE, #=1-4) is low during the TOH byte
times in the RXTB#DATA(7:0) stream and is high during the SPE byte times. This includes cases where
pointer adjustments are performed and the SPE needs to be adjusted about the H3 bytes. For example, the
H3 bytes are payload bytes during the frame in which a pointer decrement occurs; therefore, the RXTB#SPE
signal will be high coincident with the H3 bytes for that frame. Also, in the frame where a pointer increment
occurs, the three bytes after the H3 bytes become stuff, therefore the RXTB#SPE signal will be low for those
bytes.
The parity checking that the SONET/SDH framer performs can be configured on a per Telecom Bus basis
through the use of the PAR_EVEN and PAR_FULL control bits in the OR#Conf13 registers. Parity is calcu-
lated on a per Telecom Bus basis regardless of whether the interfaces work individually or as a single bus.
The receive Telecom Bus failure output (RXTB#FAIL) is generated by SONET/SDH framer in response to an
alarm condition that will cause AIS-P to be generated downstream, to tell the downstream device to generate
AIS-P in the STM-1/STS-3c in which the alarm occurred. The RXTB#FAIL output will remain active for the
duration of the alarm condition that causes it to become set.
Ring Port
A Ring Port, also known as an AIP (Alarm Indication Port), is provided on the SONET/SDH framer for ring
applications where line and path information need to be passed between SONET/SDH framers. The following
line and path information are exchanged:
• Path RDI and FEBE.
• Line RDI and FEBE.
• Debounced K1 byte.
• Debounced K2 byte and New APS Indication.
• Debounced K3 byte and New K3 byte indication.
See Operation on page 88 for a detailed description of the Ring Port.
DCC Port
There are four transmit DCC Ports and four receive DCC Ports. Each port consists of a clock output and a
corresponding data input for transmit and a corresponding output for receive. The Line DCC bytes D1-D3 or
the MS DCC D4-D12 can be processed by these ports via software control. Optionally, the DCC bytes can be
transmitted/received from the on-chip RAM.
Block Diagram and Block Descriptions
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ssframer.01
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IBM [ IBM ]
