Datasheet
KSZ8721BL/SL
DS00002813A-page 20 2018 Microchip Technology Inc.
TABLE 4-3: REGISTER 1H - BASIC STATUS
Bit Name Description Default Reference
1.15
100BASE-T4 1 = T4 capable
0 = Not T4 capable
RO 0
1.14
100BASE-TX Full-Duplex 1 = Capable of 100BASE-X full-duplex
0 = Not capable of 100BASE-X full-duplex
RO 1
1.13
100BASE-TX Half-Duplex 1 = Capable of 100BASE-X half-duplex
0 = Not capable of 100BASE-X half-duplex
RO 1
1.12
10BASE-T Full-Duplex 1 = 10 Mbps with full-duplex
0 = No 10 Mbps with full-duplex capability
RO 1
1.11
10BASE-T Half-Duplex 1 = 10 Mbps with half-duplex
0 = No 10 Mbps with half-duplex capability
RO 1
1.10:7 Reserved — RO 0
1.6 No Preamble 1 = Preamble suppression
0 = Normal preamble
RO 1
1.5 Auto-Negotiation Complete 1 = Auto-negotiation process completed
0 = Auto-negotiation process not completed
RO 0
1.4 Remote Fault 1 = Remote fault
0 = No remote fault
RO/LH
0
1.3 Auto-Negotiation Ability 1 = Capable to perform auto-negotiation
0 = Unable to perform auto-negotiation
RO 1
1.2 Link Status 1 = Link is up
0 = Link is down
RO/LL 0
1.1 Jabber Detect 1 = Jabber detected
0 = Jabber not detected. Default is low
RO/LH 0
1.0 Extended Capability 1 = Supports extended capabilities registers RO 1
TABLE 4-4: REGISTER 2H - PHY IDENTIFIER 1
Bit Name Description Default Reference
2.15:0 PHY ID Number
Assigned to the 3rd through 18th bits of the organi-
zationally unique identifier (OUI). Microchip’s OUI
is 0010A1 (hex).
RO 0022h
TABLE 4-5: REGISTER 3H - PHY IDENTIFIER 2
Bit Name Description Default Reference
3.15:0 PHY ID Number
Assigned to the 19th through 24th bits of the orga-
nizationally unique identifier (OUI). Microchip’s
OUI is 0010A1 (hex).
RO 000101
3.9:4 Model Number Six bit manufacturer’s model number RO 100001
3.3:0 Revision Number Four bit manufacturer’s model number RO 1001
TABLE 4-6: REGISTER 4H - AUTO-NEGOTIATION ADVERTISEMENT
Bit Name Description Default Reference
4.15 Next page
1 = Next page capable
0 = No next page capability
RW 0
4.14 Reserved — RO 0
4.13 Remote Fault
1 = Remote fault supported
0 = No remote fault
RW 0
4.12:11 Reserved — RO 0