10/100 Non-PCI Ethernet Single Chip MAC + PHY
Datasheet
1. LAN91C111 is set to operate in Half Duplex mode (SWFDUP=0);
2. When STP_SQET=1 and SWFDUP=0, SQET bit will be set upon completion of a transmit
operation and no SQET Pulse has occurred during the IPG (Inter Frame Gap). If a pulse has
occurred during the IPG, SQET bit will not get set.
3. Once SQET bit is set, setting the TXENA bit in TCR register, or via hardware /software reset can
clear this bit.
16COL - 16 collisions reached. Set when 16 collisions are detected for a transmit frame. TXENA bit
in TCR is reset. Cleared when TXENA is set high.
LTX_MULT - Last transmit frame was a multicast. Set if frame was a multicast. Cleared at the start
of every transmit frame.
MULCOL - Multiple collision detected for the last transmit frame. Set when more than one collision
was experienced. Cleared when TX_SUC is high at the end of the packet being sent.
SNGLCOL - Single collision detected for the last transmit frame. Set when a collision is detected.
Cleared when TX_SUC is high at the end of the packet being sent.
TX_SUC - Last transmit was successful. Set if transmit completes without a fatal error. This bit is
cleared by the start of a new frame transmission or when TXENA is set high. Fatal errors are:
■
■
■
■
■
16 collisions (1/2 duplex mode only)
SQET fail and STP_SQET = 1 (1/2 duplex mode only)
FIFO Underrun
Carrier lost and MON_CSN = 1 (1/2 duplex mode only)
Late collision (1/2 duplex mode only)
8.7
Bank 0 - Receive Control Register
OFFSET
4
NAME
TYPE
SYMBOL
RCR
RECEIVE CONTROL
REGISTER
READ/WRITE
HIGH
SOFT
FILT
CAR
ABORT_E
NB
Reserved
Reserved
Reserved
STRIP
CRC
RXEN
0
BYTE
RST
0
0
0
0
0
0
0
LOW
Reserved
Reserved
Reserved
Reserved
Reserved
ALMUL
PRMS
RX_
BYTE
ABORT
0
0
0
0
0
0
0
0
SOFT_RST - Software-Activated Reset. Active high. Initiated by writing this bit high and terminated by
writing the bit low. The LAN91C111’s configuration is not preserved except for Configuration, Base,
and IA0-IA5 Registers. EEPROM is not reloaded after software reset.
FILT_CAR - Filter Carrier. When set filters leading edge of carrier sense for 12 bit times (3 nibble
times). Otherwise recognizes a receive frame as soon as carrier sense is active. (Does NOT filter RX
DV on MII!)
SMSC LAN91C111-REV B
Revision 1.8 (07-13-05)
DATA5S9HEET