LAN83C183 Datasheet, PDF (44/113 Pages) SMSC Corporation – FAST ETHERNET PHYSICAL LAYER DEVICE

1.10 RESET
The device is reset when:
1. V_DD is applied to the device, or
2. The reset bit (RST) is set in the MI serial port Control register, or
3. The RESETn pin is asserted (LOW).
When reset occurs because of (1) or (2), an internal power-on reset pulse is
generated that resets all internal circuits, forces the MI serial port bits to their default
values, and latches in new values for the MI address. After the power-on reset pulse
has finished, the reset bit (RST) in the MI serial port Control register is cleared and
the device is ready for normal operation.
When reset is initiated because of (3), the same procedure occurs except the device
stays in the reset state as long as the RESETn pin is held LOW. The RESETn pin
has an internal pullup to V_DD. The device is guaranteed to be ready for normal
operation 50 ms after the reset sequence is initiated.
1.11 POWERDOWN
To powerdown the LAN83C183, set the Powerdown bit (PDN) in the MI serial port
Control register. In powerdown mode, the TP outputs are in a
high-impedance state, all functions are disabled except the MI serial port, and the
power consumption is reduced to a minimum. The device is guaranteed to be ready
for normal operation 500 ms after the PDN bit is cleared.
1.12
RECEIVE POLARITY CORRECTION
In 10 Mbits/s mode, the polarity of the signal on the TP receive input is continuously
monitored. If either three consecutive link pulses or one SOI pulse indicates incorrect
polarity on the TP receive input, the polarity is internally determined to be incorrect.
In this case, the Reverse Polarity Detect bit (RPOL) is set in the MI serial port Status
Output register.
The device automatically corrects for the reverse polarity condition, provided the
autopolarity feature is not disabled. To disable autopolarity, set the Autopolarity
Disable bit (APOL_DIS) in the MI serial port Configuration 2 register.
No polarity detection or correction is needed in the 100 Mbits/s mode.
SMSC DS – LAN83C183
44
Rev. 12/14/2000