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KS8721B/BT
Micrel, Inc.
M9999-030106
20
March 2006
Address Name
Description
Mode(Note 1) Default
Register 15h - RXER Counter
15.15:0
RXER Counter
RX Error counter for the RX_ER in each package
RO
0000
Register 1bh - Interrupt Control/Status Register
1b.15
Jabber Interrupt Enable
1 = Enable Jabber Interrupt; 0=Disable Jabber Interrupt
RW
0
1b.14
Receive Error
1 = Enable Receive Error Interrupt
RW
0
Interrupt Enable
0 = Disable Receive Error Interrupt
1b.13
Page Received
1 = Enable Page Received Interrupt
RW
0
Interrupt Enable
0 = Disable Page Received Interrupt
1b.12
Parallel Detect Fault
1 = Enable Parallel Detect Fault Interrupt
RW
0
Interrupt Enable
0 = Disable Parallel Detect Fault Interrupt
1b.11
Link Partner Acknowledge 1 = Enable Link Partner Acknowledge Interrupt
RW
0
Interrupt Enable
0 = Disable Link Partner Acknowledge Interrupt
1b.10
Link Down
1 = Enable Link Down Interrupt
RW
0
Interrupt Enable
0 = Disable Link Down Interrupt
1b.9
Remote Fault
1 = Enable Remote Fault Interrupt
RW
0
Interrupt Enable
0 = Disable Remote Fault Interrupt
1b.8
Link Up Interrupt Enable
1 = Enable Link Up Interrupt
RW
0
0 = Disable Link Up Interrupt
1b.7
Jabber Interrupt
1 = Jabber Interrupt Occurred
RO/SC
0
0 = Jabber Interrupt Does Not Occurred
1b.6
Receive Error Interrupt
1 = Receive Error Occurred
RO/SC
0
0 = Receive Error Does Not Occurred
1b.5
Page Receive Interrupt
1 = Page Receive Occurred
RO/SC
0
0 = Page Receive Does Not Occurred
1b.4
Parallel Detect
1 = Parallel Detect Fault Occurred
RO/SC
0
Fault Interrupt
0 = Parallel Detect Fault Does Not Occurred
1b.3
Link Partner
1 = Link Partner Acknowledge Occurred
RO/SC
0
Acknowledge Interrupt
0 = Link Partner Acknowledge Does Not Occurred
1b.2
Link Down Interrupt
1 = Link Down Occurred
RO/SC
0
0 = Link Down Does Not Occurred
1b.1
Remote Fault Interrupt
1 = Remote Fault Occurred
RO/SC
0
0 = Remote Fault Does Not Occurred
1b.0
Link Up Interrupt
1 = Link Up Interrupt Occurred
RO/SC
0
0 = Link Up Interrupt Does Not Occurred
Register 1fh - 100BaseTX PHY Controller
1f.15:14
Reserved
1f:13
Pairswap Disable
1 = Disable MDI/MDIX; 0 = Enable MDI/MDIX
R/W
0
1f.12
Energy Detect
1 = Presence of Signal on RX+/- Analog Wire Pair
RO
0
0 = No Signal Setected on RX+/-
1f.11
Force Link
1 = Force Link Pass; 0 = Normal Link Operation
R/W
0
This bit bypasses the control logic and allow transmitter
to send pattern even if there is no link.
1f.10
Power Saving
1 = Enable Ppower Saving; 0 = Disable
RW
1
1f.9
Interrupt Level
1 = Interrupt Pin Active High; 0 = Active Low
RW
0
1f.8
Enable Jabber
1 = Enable Jabber Counter; 0 = Disable
RW
1
1f.7
Auto-Negotiation Complete 1 = Auto-Negotiation Complete; 0 = Not Nomplete
RW
0
Note 1. RW: Read/Write, RO: Read only, SC: Self clear, LH: Latch High, LL: Latch Low. Some of the default values are set by strap-in. See “Srap-
ping Options.”
Address Name
Description
Mode
Address Name
Description
Mode
Address Name
Description
Mode
Default
1f.15:14
Reserved
1f:13
Pairswap Disable
1 = Disable MDI/MDIX; 0 = Enable MDI/MDIX
R/W
0
1f.12
Energy Detect
1 = Presence of Signal on RX+/- Analog Wire Pair
RO
0
0 = No Signal Setected on RX+/-
1f.11
Force Link
1 = Force Link Pass; 0 = Normal Link Operation
R/W
0
to send pattern even if there is no link.
1f.10
Power Saving
1 = Enable Ppower Saving; 0 = Disable
RW
1
1f.9
Interrupt Level
1 = Interrupt Pin Active High; 0 = Active Low
RW
0
1f.8
Enable Jabber
1 = Enable Jabber Counter; 0 = Disable
RW
1
1f.7
Auto-Negotiation Complete 1 = Auto-Negotiation Complete; 0 = Not Nomplete
RW
0
1f:13
Pairswap Disable
1 = Disable MDI/MDIX; 0 = Enable MDI/MDIX
R/W
0
1f.12
Energy Detect
1 = Presence of Signal on RX+/- Analog Wire Pair
RO
0
1f.11
Force Link
1 = Force Link Pass; 0 = Normal Link Operation
R/W
0
1f.10
Power Saving
1 = Enable Ppower Saving; 0 = Disable
RW
1
1f.9
Interrupt Level
1 = Interrupt Pin Active High; 0 = Active Low
RW
0
1f.8
Enable Jabber
1 = Enable Jabber Counter; 0 = Disable
RW
1
1f.7
Auto-Negotiation Complete 1 = Auto-Negotiation Complete; 0 = Not Nomplete
RW
0
1f:13
Pairswap Disable
1 = Disable MDI/MDIX; 0 = Enable MDI/MDIX
R/W
0
1f.12
Energy Detect
1 = Presence of Signal on RX+/- Analog Wire Pair
RO
0
0 = No Signal Setected on RX+/-
1f.11
Force Link
1 = Force Link Pass; 0 = Normal Link Operation
R/W
0
to send pattern even if there is no link.
1f.10
Power Saving
1 = Enable Ppower Saving; 0 = Disable
RW
1
1f.9
Interrupt Level
1 = Interrupt Pin Active High; 0 = Active Low
RW
0
1f.8
Enable Jabber
1 = Enable Jabber Counter; 0 = Disable
RW
1
1f.7
Auto-Negotiation Complete 1 = Auto-Negotiation Complete; 0 = Not Nomplete
RW
0
1f:13
Pairswap Disable
1 = Disable MDI/MDIX; 0 = Enable MDI/MDIX
R/W
0
1f.12
Energy Detect
1 = Presence of Signal on RX+/- Analog Wire Pair
RO
0
1f.11
Force Link
1 = Force Link Pass; 0 = Normal Link Operation
R/W
0
1f.10
Power Saving
1 = Enable Ppower Saving; 0 = Disable
RW
1
1f.9
Interrupt Level
1 = Interrupt Pin Active High; 0 = Active Low
RW
0
1f.8
Enable Jabber
1 = Enable Jabber Counter; 0 = Disable
RW
1
1f.7
Auto-Negotiation Complete 1 = Auto-Negotiation Complete; 0 = Not Nomplete
RW
0
Register 15h - RXER Counter
15.15:0
RXER Counter
RX Error counter for the RX_ER in each package
RO
0000
Register 1bh - Interrupt Control/Status Register
1b.15
Jabber Interrupt Enable
1 = Enable Jabber Interrupt; 0=Disable Jabber Interrupt
RW
0
1b.14
Receive Error
1 = Enable Receive Error Interrupt
RW
0
Interrupt Enable
0 = Disable Receive Error Interrupt
1b.13
Page Received
1 = Enable Page Received Interrupt
RW
0
Interrupt Enable
0 = Disable Page Received Interrupt
1b.12
Parallel Detect Fault
1 = Enable Parallel Detect Fault Interrupt
RW
0
Interrupt Enable
0 = Disable Parallel Detect Fault Interrupt
1b.11
Link Partner Acknowledge 1 = Enable Link Partner Acknowledge Interrupt
RW
0
Interrupt Enable
0 = Disable Link Partner Acknowledge Interrupt
1b.10
Link Down
1 = Enable Link Down Interrupt
RW
0
Interrupt Enable
0 = Disable Link Down Interrupt
1b.9
Remote Fault
1 = Enable Remote Fault Interrupt
RW
0
Interrupt Enable
0 = Disable Remote Fault Interrupt
1b.8
Link Up Interrupt Enable
1 = Enable Link Up Interrupt
RW
0
0 = Disable Link Up Interrupt
1b.7
Jabber Interrupt
1 = Jabber Interrupt Occurred
RO/SC
0
0 = Jabber Interrupt Does Not Occurred
1b.6
Receive Error Interrupt
1 = Receive Error Occurred
RO/SC
0
0 = Receive Error Does Not Occurred
1b.5
Page Receive Interrupt
1 = Page Receive Occurred
RO/SC
0
0 = Page Receive Does Not Occurred
1b.4
Parallel Detect
1 = Parallel Detect Fault Occurred
RO/SC
0
Fault Interrupt
0 = Parallel Detect Fault Does Not Occurred
1b.3
Link Partner
1 = Link Partner Acknowledge Occurred
RO/SC
0
Acknowledge Interrupt
0 = Link Partner Acknowledge Does Not Occurred
1b.2
Link Down Interrupt
1 = Link Down Occurred
RO/SC
0
0 = Link Down Does Not Occurred
1b.1
Remote Fault Interrupt
1 = Remote Fault Occurred
RO/SC
0
0 = Remote Fault Does Not Occurred
1b.0
Link Up Interrupt
1 = Link Up Interrupt Occurred
RO/SC
0
0 = Link Up Interrupt Does Not Occurred
1f.15:14
Reserved
1f:13
Pairswap Disable
1 = Disable MDI/MDIX; 0 = Enable MDI/MDIX
R/W
0
1f.12
Energy Detect
1 = Presence of Signal on RX+/- Analog Wire Pair
RO
0
0 = No Signal Setected on RX+/-
1f.11
Force Link
1 = Force Link Pass; 0 = Normal Link Operation
R/W
0
to send pattern even if there is no link.
1f.10
Power Saving
1 = Enable Ppower Saving; 0 = Disable
RW
1
1f.9
Interrupt Level
1 = Interrupt Pin Active High; 0 = Active Low
RW
0
1f.8
Enable Jabber
1 = Enable Jabber Counter; 0 = Disable
RW
1
1f.7
Auto-Negotiation Complete 1 = Auto-Negotiation Complete; 0 = Not Nomplete
RW
0
15.15:0
RXER Counter
RX Error counter for the RX_ER in each package
RO
0000
15.15:0
RXER Counter
RX Error counter for the RX_ER in each package
RO
0000
15.15:0
RXER Counter
RX Error counter for the RX_ER in each package
RO
0000
15.15:0
RXER Counter
RX Error counter for the RX_ER in each package
RO
0000
1b.15
Jabber Interrupt Enable
1 = Enable Jabber Interrupt; 0=Disable Jabber Interrupt
RW
0
1b.14
Receive Error
1 = Enable Receive Error Interrupt
RW
0
Interrupt Enable
0 = Disable Receive Error Interrupt
1b.13
Page Received
1 = Enable Page Received Interrupt
RW
0
Interrupt Enable
0 = Disable Page Received Interrupt
1b.12
Parallel Detect Fault
1 = Enable Parallel Detect Fault Interrupt
RW
0
Interrupt Enable
0 = Disable Parallel Detect Fault Interrupt
1b.11
Link Partner Acknowledge 1 = Enable Link Partner Acknowledge Interrupt
RW
0
Interrupt Enable
0 = Disable Link Partner Acknowledge Interrupt
1b.10
Link Down
1 = Enable Link Down Interrupt
RW
0
Interrupt Enable
0 = Disable Link Down Interrupt
1b.9
Remote Fault
1 = Enable Remote Fault Interrupt
RW
0
Interrupt Enable
0 = Disable Remote Fault Interrupt
1b.8
Link Up Interrupt Enable
1 = Enable Link Up Interrupt
RW
0
0 = Disable Link Up Interrupt
1b.7
Jabber Interrupt
1 = Jabber Interrupt Occurred
RO/SC
0
0 = Jabber Interrupt Does Not Occurred
1b.6
Receive Error Interrupt
1 = Receive Error Occurred
RO/SC
0
0 = Receive Error Does Not Occurred
1b.5
Page Receive Interrupt
1 = Page Receive Occurred
RO/SC
0
0 = Page Receive Does Not Occurred
1b.4
Parallel Detect
1 = Parallel Detect Fault Occurred
RO/SC
0
Fault Interrupt
0 = Parallel Detect Fault Does Not Occurred
1b.3
Link Partner
1 = Link Partner Acknowledge Occurred
RO/SC
0
Acknowledge Interrupt
0 = Link Partner Acknowledge Does Not Occurred
1b.2
Link Down Interrupt
1 = Link Down Occurred
RO/SC
0
0 = Link Down Does Not Occurred
1b.1
Remote Fault Interrupt
1 = Remote Fault Occurred
RO/SC
0
0 = Remote Fault Does Not Occurred
1b.0
Link Up Interrupt
1 = Link Up Interrupt Occurred
RO/SC
0
0 = Link Up Interrupt Does Not Occurred
1b.15
Jabber Interrupt Enable
1 = Enable Jabber Interrupt; 0=Disable Jabber Interrupt
RW
0
1b.14
Receive Error
1 = Enable Receive Error Interrupt
RW
0
1b.13
Page Received
1 = Enable Page Received Interrupt
RW
0
1b.12
Parallel Detect Fault
1 = Enable Parallel Detect Fault Interrupt
RW
0
1b.11
Link Partner Acknowledge 1 = Enable Link Partner Acknowledge Interrupt
RW
0
1b.10
Link Down
1 = Enable Link Down Interrupt
RW
0
1b.9
Remote Fault
1 = Enable Remote Fault Interrupt
RW
0
1b.8
Link Up Interrupt Enable
1 = Enable Link Up Interrupt
RW
0
1b.7
Jabber Interrupt
1 = Jabber Interrupt Occurred
RO/SC
0
1b.6
Receive Error Interrupt
1 = Receive Error Occurred
RO/SC
0
1b.5
Page Receive Interrupt
1 = Page Receive Occurred
RO/SC
0
1b.4
Parallel Detect
1 = Parallel Detect Fault Occurred
RO/SC
0
1b.3
Link Partner
1 = Link Partner Acknowledge Occurred
RO/SC
0
1b.2
Link Down Interrupt
1 = Link Down Occurred
RO/SC
0
1b.1
Remote Fault Interrupt
1 = Remote Fault Occurred
RO/SC
0
1b.0
Link Up Interrupt
1 = Link Up Interrupt Occurred
RO/SC
0
1b.15
Jabber Interrupt Enable
1 = Enable Jabber Interrupt; 0=Disable Jabber Interrupt
RW
0
1b.14
Receive Error
1 = Enable Receive Error Interrupt
RW
0
Interrupt Enable
0 = Disable Receive Error Interrupt
1b.13
Page Received
1 = Enable Page Received Interrupt
RW
0
Interrupt Enable
0 = Disable Page Received Interrupt
1b.12
Parallel Detect Fault
1 = Enable Parallel Detect Fault Interrupt
RW
0
Interrupt Enable
0 = Disable Parallel Detect Fault Interrupt
1b.11
Link Partner Acknowledge 1 = Enable Link Partner Acknowledge Interrupt
RW
0
Interrupt Enable
0 = Disable Link Partner Acknowledge Interrupt
1b.10
Link Down
1 = Enable Link Down Interrupt
RW
0
Interrupt Enable
0 = Disable Link Down Interrupt
1b.9
Remote Fault
1 = Enable Remote Fault Interrupt
RW
0
Interrupt Enable
0 = Disable Remote Fault Interrupt
1b.8
Link Up Interrupt Enable
1 = Enable Link Up Interrupt
RW
0
0 = Disable Link Up Interrupt
1b.7
Jabber Interrupt
1 = Jabber Interrupt Occurred
RO/SC
0
0 = Jabber Interrupt Does Not Occurred
1b.6
Receive Error Interrupt
1 = Receive Error Occurred
RO/SC
0
0 = Receive Error Does Not Occurred
1b.5
Page Receive Interrupt
1 = Page Receive Occurred
RO/SC
0
0 = Page Receive Does Not Occurred
1b.4
Parallel Detect
1 = Parallel Detect Fault Occurred
RO/SC
0
Fault Interrupt
0 = Parallel Detect Fault Does Not Occurred
1b.3
Link Partner
1 = Link Partner Acknowledge Occurred
RO/SC
0
Acknowledge Interrupt
0 = Link Partner Acknowledge Does Not Occurred
1b.2
Link Down Interrupt
1 = Link Down Occurred
RO/SC
0
0 = Link Down Does Not Occurred
1b.1
Remote Fault Interrupt
1 = Remote Fault Occurred
RO/SC
0
0 = Remote Fault Does Not Occurred
1b.0
Link Up Interrupt
1 = Link Up Interrupt Occurred
RO/SC
0
0 = Link Up Interrupt Does Not Occurred
1b.15
Jabber Interrupt Enable
1 = Enable Jabber Interrupt; 0=Disable Jabber Interrupt
RW
0
1b.14
Receive Error
1 = Enable Receive Error Interrupt
RW
0
1b.13
Page Received
1 = Enable Page Received Interrupt
RW
0
1b.12
Parallel Detect Fault
1 = Enable Parallel Detect Fault Interrupt
RW
0
1b.11
Link Partner Acknowledge 1 = Enable Link Partner Acknowledge Interrupt
RW
0
1b.10
Link Down
1 = Enable Link Down Interrupt
RW
0
1b.9
Remote Fault
1 = Enable Remote Fault Interrupt
RW
0
1b.8
Link Up Interrupt Enable
1 = Enable Link Up Interrupt
RW
0
1b.7
Jabber Interrupt
1 = Jabber Interrupt Occurred
RO/SC
0
1b.6
Receive Error Interrupt
1 = Receive Error Occurred
RO/SC
0
1b.5
Page Receive Interrupt
1 = Page Receive Occurred
RO/SC
0
1b.4
Parallel Detect
1 = Parallel Detect Fault Occurred
RO/SC
0
1b.3
Link Partner
1 = Link Partner Acknowledge Occurred
RO/SC
0
1b.2
Link Down Interrupt
1 = Link Down Occurred
RO/SC
0
1b.1
Remote Fault Interrupt
1 = Remote Fault Occurred
RO/SC
0
1b.0
Link Up Interrupt
1 = Link Up Interrupt Occurred
RO/SC
0