MII Management (EPHY) Registers
1060
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Ethernet Controller
Table 15-110. EPHYCFG1 Register Field Descriptions (continued)
Bit
Field
Type
Reset
Description
4
FASTANEN
R/W
0x0
Fast Auto Negotiation Enable. Adjusting these bits reduces the time
it takes to auto-negotiate between two PHYs. When using this option
care must be taken to maintain proper operation of the system.
While shortening these timer intervals may not cause problems in
normal operation, there are certain situations where this may lead to
problems.
0x0 = Disable fast auto-negotiation mode. The PHY auto-negotiates
using the normal timer setting
0x1 = Enable fast auto-negotiation mode. The PHY auto-negotiates
using the timer setting according to the FANSEL bits (bits [3:2] of
this register)
3-2
FANSEL
R/W
0x0
Fast Auto-Negotiation Select Configuration. This bit is preconfigured
at reset by the EMACPC register. For custom configuration see .
Adjusting these bits reduces the time it takes to auto-negotiate
between two PHYs. In Fast AN mode, both PHYs should be
configured to the same configuration. These two bits define the
duration for each state of the auto-negotiation process according to
the table above. The new duration time must be enabled by setting
bit 4 (FASTANEN) of this register. Using this mode in cases where
both link partners are not configured to the same fast auto-
negotiation configuration might produce scenarios with unexpected
behavior.
0x0 = Break Link Timer: 80 ms, Link Fail Inhibit Timer: 50 ms, Auto-
Negate Wait Timer: 35 ms
0x1 = Break Link Timer: 120 ms, Link Fail Inhibit Timer: 75 ms, Auto-
Negate Wait Timer: 50 ms
0x2 = Break Link Timer: 240 ms, Link Fail Inhibit Timer: 150 ms,
Auto-Negate Wait Timer: 100 ms
0x3 = Reserved
1
FRXDVDET
R/W
0x0
FAST RXDV Detection. Enabling this feature allows the PHY to pass
data to the MII interface earlier. This bit is set to disabled if using the
EMACPC register bits to program the PHY configuration.
0x0 = Disable fast RXDV detection. The PHY operates in normal
mode where an internally asserted RXDV signal is sent to the MII
interface after detection of /J/K/.
0x1 = An internal RXDV signal is asserted high on receive packet
due to detection of /J/ symbol only. Fast RXDV detection allows the
PHY to pass data to the MII interface earlier. If a consecutive /K/
does not appear, RXERR is generated.
0
RESERVED
R
0x0