Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK Data Sheet

Product codes
AT91SAM9M10-G45-EK
Page of 1361
 743
SAM9M10 [DATASHEET]
6355F–ATARM–12-Mar-13
 
36.6.1
Network  Control  Register
Name:
EMAC_NCR
Address:
0xFFFBC000
Access:
Read-write
• LB:  LoopBack
Asserts the loopback signal to the PHY.
• LLB:  Loopback  local
Connects 
txd
to 
rxd
tx_en
to 
rx_dv
, forces full duplex and drives 
rx_clk
and 
tx_clk
with 
pclk
divided by 4.
rx_clk
and 
tx_clk
may glitch as the EMAC is switched into and out of internal loop back. It is important that receive
and transmit circuits have already been disabled when making the switch into and out of internal loop back.
• RE:  Receive  enable 
When set, enables the EMAC to receive data. When reset, frame reception stops immediately and the receive FIFO is
cleared. The receive queue pointer register is unaffected.
• TE:  Transmit  enable 
When set, enables the Ethernet transmitter to send data. When reset transmission, stops immediately, the transmit FIFO
and control registers are cleared and the transmit queue pointer register resets to point to the start of the transmit descrip-
tor list.
• MPE:  Management  port  enable
Set to one to enable the management port. When zero, forces MDIO to high impedance state and MDC low.
• CLRSTAT:  Clear  statistics  registers
This bit is write only. Writing a one clears the statistics registers.
• INCSTAT:  Increment  statistics  registers
This bit is write only. Writing a one increments all the statistics registers by one for test purposes.
• WESTAT:  Write  enable  for  statistics  registers 
Setting this bit to one makes the statistics registers writable for functional test purposes.
• BP:  Back  pressure
If set in half duplex mode, forces collisions on all received frames.
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
THALT
TSTART
BP
7
6
5
4
3
2
1
0
WESTAT
INCSTAT
CLRSTAT
MPE
TE
RE
LLB
LB