lan9312 Standard Microsystems Corp., lan9312 Datasheet - Page 61

• Manufacturer Part Number: lan9312
• Description: Lan9312 High Performance Two Port 10/100 Managed Ethernet Switch With 32-bit Non-pci Cpu Interface
• Manufacturer: Standard Microsystems Corp.

High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface
Datasheet
SMSC LAN9312
6.3.1.1
"Flow Control Enable Logic," on page
the switch engine. Non-pause control frames are optionally filtered or forwarded.
When the receive FIFO is full and additional data continues to be received, an overrun condition occurs
and the frame is discarded (FIFO space recovered) or marked as a bad frame.
The receive MAC can be disabled from receiving all frames by clearing the RX Enable bit of the
x MAC Receive Configuration Register
The size of the RX FIFO is 256 bytes. If a bad packet with less than 64 bytes is received, it will be
flushed from the FIFO automatically and the FIFO space recovered. Packets equal to or larger than
64 bytes with an error will be marked and reported to the switch engine. The switch engine will
subsequently drop the packet.
Receive Counters
The receive MAC gathers statistics on each packet and increments the related counter registers. The
following receive counters are supported for each switch fabric port. Refer to
Accessible Switch Control and Status Registers,” on page 308
Section 14.5.2.22
Total undersized packets
Total packets 64 bytes in size
Total packets 65 through 127 bytes in size
Total packets 128 through 255 bytes in size
Total packets 256 through 511 bytes in size
Total packets 512 through 1023 bytes in size
Total packets 1024 through maximum bytes in size
Total oversized packets
Total OK packets
Total packets with CRC errors
Total multicast packets
Total broadcast packets
Total MAC Pause packets
Total fragment packets
Total jabber packets
Total alignment errors
Total bytes received from all packets
Total bytes received from good packets
Total packets with a symbol error
Total MAC control packets
for detailed descriptions of these counters.
(Section 14.5.2.11, on page
(Section 14.5.2.17, on page
(Section 14.5.2.18, on page
(Section 14.5.2.13, on page
(Section 14.5.2.16, on page
(Section 14.5.2.10, on page
(Section 14.5.2.14, on page
(Section 14.5.2.3, on page
(Section 14.5.2.15, on page
(Section 14.5.2.22, on page
(Section 14.5.2.4, on page
(Section 14.5.2.12, on page
DATASHEET
(Section 14.5.2.21, on page
58. Pause frames are consumed by the MAC and not sent to
(MAC_RX_CFG_x).
(Section 14.5.2.19, on page
61
(Section 14.5.2.20, on page
(Section 14.5.2.5, on page
(Section 14.5.2.7, on page
(Section 14.5.2.6, on page
(Section 14.5.2.8, on page
333)
339)
340)
(Section 14.5.2.9, on page
335)
338)
332)
325)
336)
337)
344)
326)
334)
343)
341)
and
342)
327)
Section 14.5.2.3
329)
328)
330)
Table 14.12, “Indirectly
Revision 1.2 (04-08-08)
331)
through
Port