SAM3X8E Atmel Corporation, SAM3X8E Datasheet - Page 1290

• Manufacturer Part Number: SAM3X8E
• Manufacturer: Atmel Corporation

41.6.6
Name:
Address:
Access:
This register points to the entry in the transmit buffer queue (descriptor list) currently being used. It is written with the start
location of the transmit buffer descriptor list. The lower order bits increment as buffers are used up and wrap to their original
values after either 1024 buffers or when the wrap bit of the entry is set. This register can only be written when bit 3 in the
transmit status register is low.
As transmit buffer reads consist of bursts of two words, it is recommended that bit 2 is always written with zero to prevent a
burst crossing a 1K boundary, in violation of section 3.6 of the AMBA specification.
• ADDR:
Written with the address of the start of the transmit queue, reads as a pointer to the first buffer of the frame being transmit-
ted or about to be transmitted.
1290
1290
31
23
15
7
SAM3X/A
SAM3X/A
Transmit buffer queue pointer address
Transmit Buffer Queue Pointer Register
EMAC_TBQP
0x400B001C
Read-write
30
22
14
6
29
21
13
5
ADDR
28
20
12
4
ADDR
ADDR
ADDR
27
19
11
3
26
18
10
2
25
17
9
1
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24
16
8
0
–