.
: , ,
. . FIFO , . ISA. (PCI).
IEEE 802.3 . (TPSR), (TBCR0, TBCR1) TXP (transmit packet) .
, . DMA (FIFO). DMA , , TXE (transmit enable) . , , . . (threshold), DMA . , (TBCR0 TBCR1). 4 , . , , jam (32 , , ), , trunceted Binary Exponential Backoff Routine.
, PTX (complete packet transmitted) TXE (packet transmit aborted) Interrupt Status , . RSR (Receive Status ) TSR (Transmit Status ) .
PTX , TSR (DFR). TSR , (CRS), (CDH) (COL). NCR . 512- (slot time), OWC (Out of Window Collision) TSR .
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TXE ISR , 16 , FIFO . - 16 , ABT TSR . , DMA , FU (FIFO Underrun) TSR . .
, CSMA/CD , . . , . .
( CRS ), () (SFD, ). SFD (FIFO). 6 , , , , DMA . , . , , DMA . . .
SFD ( ) CRC . . , CRS , , CRC , . , (CRC RSR ), . CRS , (FAE RSR ). CRC .
, SFD , , . , 48- , (PAR0-PAR5). , , . , . , on-chip -. , CRC (Cyclic Redundency Check) , 64- (MAF0 MAF7).
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CRC , 6 (multicast address filter, MAF). , , .
, . , . MAF .
, . PR0 RCR (recieve configuration register) . MAF .
(RCR) , . RCR , . MON RCR , , , , .