74
FIGURE 11 - INTERRUPT GENERATION FOR TRANSMIT, RECEIVE, MMU
TX
FIFO
TX COMPLETION
FIFO
RX
FIFO

CSMA/CD

LOGICAL
ADDRESSPACKET #

MMU

PHYSICAL ADDRESS

RAM

CPU ADDRESS CSMA ADDRESS
RX PACKET
NUMBER
RX FIFO
PACKET NUMBER
PACKET NUMBER
REGISTER
PACK # OUT
M.S. BIT ON LY
'EMPTY'
'NOT EMPTY'
TX DONE
PACKET NUMBER
'NOT EMPTY'
INTERRUPT
STATUS REGISTER
RCV
INT
TX EMPTY
INT
TX
INT
ALLOC
INT
TWO
OPTIONS