LAN9353 Datasheet, PDF (227/523 Pages) Microchip Technology – Interfaces at up to 200Mbps via Turbo MII

LAN9353
TABLE 10-5: SWITCH FABRIC FLOW CONTROL ENABLE LOGIC
-
1
X
X
X
Half
X
X
X
X
0
BP_EN_x
-
X
0
X
X
Half
X
X
X
X
0
BP_EN_x
-
1
X
X
X
Full
X
X
X
X
RX_FC_x TX_FC_x
-
X
0
X
X
Full
X
X
X
X
RX_FC_x TX_FC_x
1
0
1
0
X
X
X
X
X
X
0
0
2
0
1
1
0
Half (Note 2)
X
X
X
X
0
BP_EN_x
3
0
1
1
1
Half
X
X
X
X
0
BP_EN_x
4
0
1
1
1
Full
0
0
X
X
0
0
5
0
1
1
1
Full
0
1
0
X
0
0
6
0
1
1
1
Full
0
1
1
0
0
0
7
0
1
1
1
Full
0
1
1
1
0
1
8
0
1
1
1
Full
1
0
0
X
0
0
9
0
1
1
1
Full
1
X
1
X
1
1
10 0
1
1
1
Full
1
1
0
0
0
0
11 0
1
1
1
Full
1
1
0
1
1
0
Note 2: If Auto-Negotiation is enabled and complete, but the link partner is not Auto-Negotiation capable, half-duplex
is forced via the parallel detect function.
Note 3: These are the bits from the PHYs’ Auto-Negotiation Advertisement and Auto-Negotiation Link Partner Base
Ability Registers. If a Switch Fabric Port is connected to a Virtual PHY, these are the local/partner swapped
outputs from the Virtual PHY’s Auto-Negotiation Advertisement and Auto-Negotiation Link Partner Base
Ability Registers. Refer to the Virtual PHY Auto-Negotiation section for more information.
Per Table 10-5, the following cases are possible:
• Case 1 - Auto-Negotiation is still in progress. Since the result is not yet established, flow control is disabled.
• Case 2 - Auto-Negotiation is enabled and unsuccessful (link partner not Auto-Negotiation capable). The link part-
ner ability is undefined, effectively a don’t-care value, in this case. The duplex setting will default to half-duplex in
this case. Flow control is determined by the BP_EN_x bit.
• Case 3 - Auto-Negotiation is enabled and successful with half-duplex as a result. The link partner ability is unde-
fined since it only applies to full-duplex operation. Flow control is determined by the BP_EN_x bit.
• Cases 4-11 -Auto-Negotiation is enabled and successful with full-duplex as the result. In these cases, the adver-
tisement registers and the link partner ability controls the RX and TX enables. These cases match IEEE 802.3
Annex 28B.3.
- Cases 4,5,6,8,10 - No flow control enabled
- Case 7 - Asymmetric pause towards partner (away from switch port)
- Case 9 - Symmetric pause
 2015 Microchip Technology Inc.
DS00001925A-page 227