DM9000_09 DAVICOM [Davicom Semiconductor, Inc.], DM9000_09 Datasheet - Page 15

• Manufacturer Part Number: DM9000_09
• Description: ISA to Ethernet MAC Controller with Integrated 10/100 PHY
• Manufacturer: DAVICOM [Davicom Semiconductor, Inc.]

6.7 RX Status Register ( 06H )
6.8 Receive Overflow Counter Register ( 07H )
6.9 Back Pressure Threshold Register (08H)
Final
Version: DM9000-DS-F03
April 23, 2009
6:0
Bit
7:4
3:0
Bit
Bit
7
7
6
5
4
3
2
1
0
Name
RXFU
RWTO
ROC
BPHW
Name
Name
FOE
LCS
PLE
JPT
MF
CE
RF
AE
Default
3H, RW
7H, RW
Default
Default
0,R/C
0,R/C
0,RO
0,RO
0,RO
0,RO
0,RO
0,RO
0,RO
0,RO
Runt Frame
It is set to indicate that the size of the received frame is smaller than 64 bytes
Multicast Frame
It is set to indicate that the received frame has a multicast address
Late Collision Seen
It is set to indicate that a late collision is found during the frame reception
Receive Watchdog Time-Out
It is set to indicate that it receives more than 2048 bytes
Physical Layer Error
It is set to indicate that a physical layer error is found during the frame reception
Alignment Error
It is set to indicate that the received frame ends with a non-byte boundary
CRC Error
It is set to indicate that the received frame ends with a CRC error
FIFO Overflow Error
It is set to indicate that a FIFO overflow error happens during the frame reception
Receive Overflow Counter Overflow
This bit is set when the ROC has an overflow condition
Receive Overflow Counter
This is a statistic counter to indicate the received packet count upon FIFO overflow
Back Pressure High Water Overflow Threshold. MAC will generate the jam pattern
when RX SRAM free space is lower than this threshold value
Default is 3K-byte free space. Please do not exceed SRAM size
(1 unit=1K bytes)
Jam Pattern Time. Default is 200us
bit3 bit2 bit1 bit0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
ISA to Ethernet MAC Controller with Integrated 10/100 PHY
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
100us
150us
200us
250us
300us
350us
400us
450us
500us
550us
600us
time
10us
15us
25us
50us
5us
Description
Description
Description
DM9000
15