April 2005 21 M9999-041405
KS8721CL Micrel, Inc.
Address Name Description Mode
(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 has not occurred.
1b.6 Receive Error Interrupt 1 = Receive error occurred. RO/SC 0
0 = Receive error has not occurred.
1b.5 Page Receive Interrupt 1 = Page receive occurred. RO/SC 0
0 = Page receive has not occurred.
1b.4 Parallel Detect 1 = Parallel detect fault occurred. RO/SC 0
Fault Interrupt 0 = Parallel detect fault has not occurred.
1b.3 Link Partner 1 = Link partner acknowledge occurred. RO/SC 0
Acknowledge Interrupt 0 = Link partner acknowledge has not occurred.
1b.2 Link Down Interrupt 1 = Link down occurred. RO/SC 0
0 = Link down has not occurred.
1b.1 Remote Fault Interrupt 1 = Remote fault occurred. RO/SC 0
0 = Remote fault has not occurred.
1b.0 Link Up Interrupt 1 = Link up interrupt occurred. RO/SC 0
0 = Link up interrupt has not occurred.
Register 1fh - 100BASE-TX PHY Controller
1f.15:14 Reserved
1f:13 Pairswap Disable 1 = Disable MDI/MDI-X; 0 = Enable MDI/MDI-X. R/W 0
1f.12 Energy Detect 1 = Presence of signal on RX+/RX- analog wire pair. RO 0
0 = No signal detected on RX+/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 power-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 complete. 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 “Strapping
Options.”