FEAST Fast Ethernet Controller for PCMCIA and Generic 16-Bit Applications
Datasheet
ISR
Save Bank Select & Address
Ptr Registers
Mask SMC91C100FD
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 SMC91C100FD
Interrupts
Exit ISR
Enqueue Packet
Set "Ready for Packet" Flag
Return Buffers to Upper Layer
Disable Allocation Interrupt
Mask
Figure 5.3 – Interrupt Service Routine
SMSC LAN91C110 Rev. B
Page 41
DATASHEET
Revision 1.0 (11-04-08)