Rainbow Electronics AT91CAP9S250A User Manual
Page 835
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835
6264A–CAP–21-May-07
AT91CAP9S500A/AT91CAP9S250A
42.5.26.11
Transmit Underrun Errors Register
Register Name:
EMAC_TUND
Access Type:
Read/Write
• TUND: Transmit Underruns
An 8-bit register counting the number of frames not transmitted due to a transmit DMA underrun. If this register is incre-
mented, then no other statistics register is incremented.
42.5.26.12
Carrier Sense Errors Register
Register Name:
EMAC_CSE
Access Type:
Read/Write
• CSE: Carrier Sense Errors
An 8-bit register counting the number of frames transmitted where carrier sense was not seen during transmission or where
carrier sense was deasserted after being asserted in a transmit frame without collision (no underrun). Only incremented in
half-duplex mode. The only effect of a carrier sense error is to increment this register. The behavior of the other statistics
registers is unaffected by the detection of a carrier sense error.
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
TUND
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
CSE