Atmel Evaluation Kit AT91SAM9G25-EK AT91SAM9G25-EK Data Sheet

Product codes
AT91SAM9G25-EK
Page of 1102
1012
SAM9G25 [DATASHEET]
11032C–ATARM–25-Jan-13
45.6.4 Transmit Status Register
Name:
EMAC_TSR
Address:
0xF802C014
Access:
Read-write
This register, when read, provides details of the status of a transmit. Once read, individual bits may be cleared by writing 1 to 
them. It is not possible to set a bit to 1 by writing to the register.
• UBR: Used Bit Read
Set when a transmit buffer descriptor is read with its used bit set. Cleared by writing a one to this bit.
• COL: Collision Occurred
Set by the assertion of collision. Cleared by writing a one to this bit.
• RLES: Retry Limit exceeded
Cleared by writing a one to this bit.
• TGO: Transmit Go
If high transmit is active.
• BEX: 
Buffers exhausted mid frame
If the buffers run out during transmission of a frame, then transmission stops, FCS shall be bad and tx_er asserted. Cleared by 
writing a one to this bit.
• COMP: Transmit Complete
Set when a frame has been transmitted. Cleared by writing a one to this bit.
• UND: Transmit Underrun
Set when transmit DMA was not able to read data from memory, either because the bus was not granted in time, because a not 
OK 
hresp(bus error) 
was returned or because a used bit was read midway through frame transmission. If this occurs, the 
transmitter forces 
bad 
CRC. Cleared by writing a one to this bit.
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
UND
COMP
BEX
TGO
RLES
COL
UBR