AT32UC3C1512C Automotive Atmel Corporation, AT32UC3C1512C Automotive Datasheet - Page 501

• Manufacturer Part Number: AT32UC3C1512C Automotive
• Manufacturer: Atmel Corporation

24.6
24.6.1
24.6.2
Figure 24-2. Receive Buffer List
9166C–AVR-08/11
Programming Interface
Configuration
Receive Buffer List
Receive Buffer Queue Pointer
(MAC Register)
Initialization of the MACB configuration (e.g. frequency ratios) must be done while the transmit
and receive circuits are disabled. Network control register and network configuration register are
described below.
Receive data is written to areas of data (i.e., buffers) in system memory. These buffers are listed
in another data structure that also resides in main memory. This data structure (receive buffer
queue) is a sequence of descriptor entries as defined in
page
To create the list of buffers:
1. Allocate a number (n) of buffers of 128 bytes in system memory.
2. Allocate an area 2n words for the receive buffer descriptor entry in system memory and
3. If less than 1024 buffers are defined, the last descriptor must be marked with the wrap
4. Write address of receive buffer descriptor entry to MACB register receive buffer queue
5. The receive circuits can then be enabled by writing to the address recognition registers
489. It points to this data structure.
create n entries in this list. Mark all entries in this list as owned by MACB, i.e., bit 0 of
word 0 set to 0.
bit (bit 1 in word 0 set to 1).
pointer.
and then to the network control register.
Description List
Receive Buffer
(In Memory)
”Receive Buffer Descriptor Entry” on
Receive Buffer N
Receive Buffer 0
Receive Buffer 1
(In Memory)
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