Mac interrupt status register – Rainbow Electronics AT75C220 User Manual
Page 43
AT75C220
43
MAC Interrupt Status Register
Register Name: ETH_ISR
Access Type: Read/write
Reset Value: 0x0
•
DONE
Management done. The PHY maintenance register has completed its operation. Cleared on read.
•
RCOM
Receive complete. A frame has been stored in memory. Cleared on read.
•
RBNA
Receive buffer not available. Cleared on read.
•
TOVR
Transmit buffer overrun. Software wrote to the address register or length register when bit 4 of the transmit status reg-
ister was not set. Cleared on read.
•
TUND
Transmit error. Ethernet transmit buffer underrun. The transmit DMA did not complete fetch frame data in time for it to
be transmitted. Cleared on read.
•
TRLE
Transmit error. Retry limit exceeded. Cleared on read.
•
TBRE
Transmit buffer register empty. Software may write a new buffer address and length to the transmit DMA controller.
Cleared by having one frame ready to transmit and another in the process of being transmitted. Cleared on read.
•
TCOM
Transmit complete. Set when a frame has been transmitted. Cleared on read.
•
LINK
Set when LINK pin changes value. Optional.
•
TIDLE
Transmit idle. Set when all frames have been transmitted. Cleared on read.
•
ROVR
RX overrun. Set when the RX overrun status bit is set. Cleared on read.
•
HRESP
HRESP not OK. Set when the DMA block sees HRESP not OK. Cleared on read.
31
30
29
28
27
26
25
24
–
–
–
–
–
–
–
–
23
22
21
20
19
18
17
16
–
–
–
–
–
–
–
–
15
14
13
12
11
10
9
8
–
–
–
–
HRESP
ROVR
LINK
TIDLE
7
6
5
4
3
2
1
0
TCOM
TBRE
RTRY
TUND
TOVR
RBNA
RCOM
DONE