LAN91C100 Datasheet, PDF (55/101 Pages) SMSC Corporation – FEAST™ Fast Ethernet Controller

ISR
Save Bank Select & Address
Ptr Registers
Mask SMC91C100 Interrupts
Read Interrupt Register
Call TX INTR or TXEMPTY
INTR
Get Next TX
No
Yes
RX INTR?
Yes
TX INTR?
No
Call RXINTR
Packet
Available for
Yes ^{Transmission?}
No
Call ALLOCATE
ALLOC INTR?
No
Yes
Write Allocated Pkt # into
Packet Number Reg.
Write Ad Ptr Reg. & Copy Data
& Source Address
Yes
Call EPH INTR
EPH INTR?
No
Restore Address Pointer &
Bank Select Registers
Unmask SMC91C100
Interrupts
Exit ISR
Enqueue Packet
Set "Ready for Packet" Flag
Return Buffers to Upper Layer
Disable Allocation Interrupt
Mask
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