RELEASED
PM73123 AAL1GATOR-8
DATASHEET
PMC-2000097
ISSUE 2
8 LINK CES/DBCES AAL1 SAR
Figure 95 SNK_INTF Start-of-Transfer Timing (Utopia 1 PHY Mode)
TPHY_CLK(i)
TPHY_ADDR(i)
TPHY_CLAV(o)
TPHY_DATA(i)
TPHY_PAR(i)
TPHY_SOC(i)
TPHY_ENB(i)
Input must be same UI_SNK_ADDR_CFG register
D1
P1
D2
P2
D3
P3
D4
P4
In Utopia 2 single address mode, a cell transfer is started as a result of an ATM
master polling the SNK_INTF with an address matching the value in the
UI_SNK_ADDR_CFG register. The SNK_INTF responds by asserting
TPHY_CLAV the cycle after UI_SNK_RADR matches the UI_SNK_ADDR_CFG
register value. Selection occurs when the value on the TPHY_ADDR matches
the configured address during the cycle before UI_SNK_RENB is brought low.
This is shown in Figure 96 below. The SNK_INTF will accept data as long as
TPHY_ENB is asserted and it has room. Data transfer pausing is supported in
Utopia 2 single address PHY mode, thus if TPHY_ENB is deasserted as in
Figure 96 the data transfer is paused. Furthermore, in Utopia 2 single address
mode, although a cell transfer has been started, additional polling may show
TPHY_CLAV as being asserted if there is still room in the sink FIFO as shown at
the end of Figure 96.
Figure 96 SNK_INTF Start-of-Transfer Utopia 2 PHY Mode
TPHY_CLK(i)
TPHY_ADDR(i)
TPHY_CLAV(o)
TPHY_DATA(o)
TPHY_PRTY(o)
TPHY_SOC(o)
TPHY_ENB(i)
ADDR
ADDR
ADDR
D1
P1
D2
P2
D3
P3
D4
P4
If the current cell being transferred will fill up the last of the four cell slots in the
sink MCFF FIFO, then the TPHY_CLAV signal will be deasserted by the D10 or
PMC-SIERRA, INC. PROPRIETARY AND CONFIDENTIAL
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PMC [ PMC-SIERRA, INC ]
