Released
Datasheet
PM73487 QRT
PMC-Sierra, Inc.
PMC-980618
Issue 3
622 Mbps ATM Traffic Management Device
2.4.2.1.2 Multiplexed Status Polling (MSP) Using Four Cell Available Signals
With MSP using four cell available signals, up to four cell available responses occur every two
clocks. The advantage offered by the MSP mode is the improved response time for PHY service
selection. With this method, it is possible to poll 31 devices in a single cell time. PHY devices,
however, must comply with this optional part of the UTOPIA Level 2 specification. A standard
PHY device can be configured to use this mode even though it does not support it directly. To
effect this, up to eight PHY devices can be configured with the addresses 0, 4, 8, 12, 16, 20, 24,
and 28. Figure 23 shows the receive UTOPIA 50 MHz MSP, including cell transfer.
1 2 3 4 5 6 7 8 9 1011 1213 1415 1617 18 1920 2122 2324 2526 27 2829 30
ATM_CLK
RATM_DATA(15:0)
RATM_ADD(4:0)
/RATM_READ_EN
RATM_CLAV(3:0)
RATM_SOC
h
h
h
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
p
02
1F 00 1F 04 1F 08 1F 0C 1F 10 1F 14 1F 18 1F 1C
1F
00
3
0
3
0
8
0
3
Figure 23. Receive UTOPIA Multiplexed Status Polling (MSP), Including Cell Transfer
Figure 24 shows the transmit UTOPIA 50 MHz MSP including cell transfer.
1 2 3 4 5 6 7 8 9 10 1112 1314 1516 1718 1920 2122 2324 2526 2728 2930
ATM_CLK
TATM_DATA(15:0)
TATM_ADD(4:0)
/TATM_WRITE_EN
TATM_CLAV(3:0)
TATM_SOC
h
h
h
p
p
p
p
p
p
p
p
p
p
p
p
p
p
0
p
p
p
p
p
p
p
p
p
p
h
00 1F 00 1F 04 1F 08 1F 0C 1F 10 1F 14 1F 18 1F 1C
1F
01 1F
0
F
0
F
0
8
F
TATM_PARITY
Figure 24. Transmit UTOPIA 50 MHz Multiplexed Status Polling (MSP), Including Cell Transfer
22
PMC [ PMC-SIERRA, INC ]
