LAN91C111 Datasheet, PDF (44/125 Pages) SMSC Corporation – 10/100 Non-PCI Ethernet Single Chip MAC + PHY

LAN91C111
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)
• 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
RECEIVE CONTROL
REGISTER
TYPE
SYMBOL
READ/WRITE
RCR
HIGH
BYTE
LOW
BYTE
SOFT
RST
0
Reserved
FILT
CAR
0
Reserved
ABORT_E
NB
0
Reserved
Reserved
0
Reserved
0
0
0
0
Reserved
0
Reserved
0
Reserved
0
ALMUL
0
STRIP
CRC
0
PRMS
0
RXEN
0
RX_
ABORT
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 rec-
ognizes a receive frame as soon as carrier sense is active. (Does NOT filter RX DV on MII!)
ABORT_ENB - Enables abort of receive when collision occurs. Defaults low. When set, the LAN91C111 will automati-
cally abort a packet being received when the appropriate collision input is activated. This bit has no effect if the SWFDUP
bit in the TCR is set.
STRIP_CRC - When set, it strips the CRC on received frames. As a result, both the Byte Count and the frame format
do not contain the CRC. When clear, the CRC is stored in memory following the packet. Defaults low.
RXEN - Enables the receiver when set. If cleared, completes receiving current frame and then goes idle. Defaults low
on reset.
ALMUL - When set accepts all multicast frames (frames in which the first bit of DA is '1'). When clear accepts only the
multicast frames that match the multicast table setting. Defaults low.
PRMS - Promiscuous mode. When set receives all frames. Does not receive its own transmission unless it is in Full
Duplex!
RX_ABORT - This bit is set if a receive frame was aborted due to length longer than 2K bytes. The frame will not be
received. The bit is cleared by RESET or by the CPU writing it low.
Reserved - Must be 0.
DS00002276A-page 44
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