CN8237EBGB Mindspeed Technologies, CN8237EBGB Datasheet - Page 282

• Manufacturer Part Number: CN8237EBGB
• Description: ATM SAR 622Mbps 3.3V ABR/CBR/GFR/UBR/VBR 456-Pin BGA
• Manufacturer: Mindspeed Technologies

Specifications of CN8237EBGB

• Package: 456BGA
• Traffic Class: ABR|CBR|GFR|UBR|VBR
• Utopia Type: Level 1|Level 2
• Host Interface: PCI
• Maximum Data Rate: 622 Mbps
• Typical Operating Supply Voltage: 3.3 V
• Minimum Operating Supply Voltage: 3.135 V

13.0 ATM UTOPIA Interface
13.5 UTOPIA Level 1 Mode Cell Handshake Timing
Figure 13-2. Receive Timing in UTOPIA Level 1 Mode with Cell Handshake
13-10
NOTE(S):
(1)
(2)
(3)
RXD/RXPAR
(RXFLAG*)
(RXMARK)
Once a cell transfer is started, RxClav (RxFlag*) is not sampled until the end of the cell.
RxEN* goes active only if there is room in the receive FIFO buffer for a complete cell.
RxEN* goes inactive at cell boundaries if the receive FIFO buffer cannot accept another cell.
RXCLAV
RXSOC
RXCLK
RXEN*
(2)
13.5 UTOPIA Level 1 Mode Cell Handshake
Timing
If high, the UTOPIA_MODE bit in the CONFIG0 register selects cell-level
handshaking. Received data is latched from the RxDATA[15:0] and RxPar lines on
the rising edge of RxClk, after RxEN* is sampled active (see
parity computed over the RxData[15:0] lines is compared to the RxPar input. If in
error, the FR_PAR_ERR bit is set in the HOST_ISTAT0 register. Data is discarded
upon a parity error if the RSM_PHALT bit in the RSM_CTRL register is set to a
logic high and the reassembly coprocessor halts. The RxSOC (RxMARK*) signals
to the CN8237 the start of cell. The RxClav (RxFLAG*) input is the physical layer
FIFO buffer empty signal. When it is active, a complete cell is not present in the
physical receive FIFO buffer. The physical layer device sets RxClav (RxFLAG*)
active when it has a complete cell to transfer. The CN8237 sets RxEN* to a logic
low if it can accept a complete cell. On the clock cycle after the last octet of a cell is
transferred, the CN8237 samples the RxClav (RxFLAG*) input. If low, the physical
device does not have a cell to transfer. If RxClav (RxFLAG*) is high, the physical
device has another cell to transfer and the CN8237 immediately starts receiving the
next cell if it can accept a complete cell.
H1
H2
Mindspeed Technologies
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(1)
P47
ATM OC-12 ServiceSAR Plus with xBR Traffic Management
P48
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H1
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Figure
(3)
28237-DSH-001-C
P48
13-2). The odd
CN8237
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