DS580 Datasheet, PDF (14/42 Pages) Xilinx, Inc – Optional MDIO interface for PHY access

LogiCORE IP XPS Ethernet Lite Media Access Controller
When the Status bit is ’0’, the Ethernet Lite MAC will monitor the ethernet for packets with a destination address
that matches its MAC address or the broadcast address. If a packet satisfies either of these conditions, the packet is
received and stored in dual port memory starting at address offset 0x1000.
Once the packet has been received, the Ethernet Lite MAC verifies the CRC. If the CRC value is correct, the status
bit is set. If the CRC bit is incorrect, the status bit is not set and the Ethernet Lite MAC resumes monitoring the eth-
ernet bus. Also, if the Ethernet Lite MAC core receive Runt Frame (frame length less than the 60 Bytes) with valid
CRC, the core will not set the status bit and interrupt will not be generated.
Once the Status bit is set, the Ethernet Lite MAC will not perform any receive operations until the bit has been
cleared to ’0’ by software indicating that all of the receive data has been retrieved from the dual port memory.
X-Ref Target - Figure 10
addr offset
0x0
addr offset
0x17FC
destination
address
source
address
type/
length
data
CRC
not
used
6
6
2
variable (0 - 1500)
4
variable
4
DS580_10_041910
Figure 10: Receive Dual Port Memory
Receive Dual Port Memory Register Description
This section tabulates the receive dual port memory registers and their reset values. All these register can be access
by single word transaction only. Burst write to these registers will not have any effect on the registers and burst read
from these register will return ‘0’.
Receive Control Register (Ping)
The Receive Control Register for ping buffer is an 32-bit read/write register as shown in Figure 11. This register is
used to inform about the availability of new packet in the ping buffer. The bit definition and accessibility of this reg-
ister is shown in Table 5.
X-Ref Target - Figure 11
Reserved
Interrupt
Enable (I) ^Status(S)
0
27 28 29 30 31
DS580_11_041910
Figure 11: Receive Control Register
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DS580 September 21, 2010
Product Specification