AM79C976 Advanced Micro Devices, AM79C976 Datasheet - Page 203

• Manufacturer Part Number: AM79C976
• Description: PCnet-PRO 10/100 Mbps PCI Ethernet Controller
• Manufacturer: Advanced Micro Devices

6
5
4
3
2
1
8/01/00
LNKSE
RCVME
XMTE
RES
RCVE
SFBDE
is set, a value of 1 will be passed
to the LEDOUT bit in this register
in Link Pass state.
is cleared by H_RESET and is
not affected by S_RESET or set-
ting the STOP bit.
When this bit is set, a value of 1 is
passed to the LEDOUT bit in this
register when there is receive ac-
tivity on the network that has
passed the address match func-
tion for this node. All address
matching modes are included:
physical, logical filtering, broad-
cast, and promiscuous.
Read/Write accessible. RCVME
is cleared by H_RESET and is
not affected by S_RESET or set-
ting the STOP bit.
this bit is set, a value of 1 is
passed to the LEDOUT bit in this
register when there is transmit
activity on the network.
Read/Write accessible. XMTE is
set to 1 by H_RESET and is not
affected by S_RESET or setting
the STOP bit.
read as zeros.
this bit is set, a value of 1 is
passed to the LEDOUT bit in this
register when there is receive ac-
tivity on the network.
Read/Write accessible. RCVE is
set to 1 by H_RESET and is not
affected by S_RESET or setting
the STOP bit.
able. When this bit is set, a value
of 1 is passed to the LEDOUT bit
in this register when the RXD[3:0]
pins are presenting the least sig-
nificant nibble of valid frame data.
Link Status Enable. When this bit
Read/Write accessible. LNKSE
Receive Match Status Enable.
Transmit Status Enable. When
Reserved location. Written and
Receive Status Enable. When
Start Frame/Byte Delimiter En-
P R E L I M I N A R Y
Am79C976
0
BCR6 controls the function(s) that the LED2 pin dis-
plays. Multiple functions can be simultaneously enabled
on this LED pin. The LED display will indicate the logical
OR of the enabled functions. BCR5 defaults to 100 Mb/
s speed indication (100E = 1) with pulse stretcher en-
abled (PSE = 1).
Note: When LEDPE (BCR2, bit 12) is set to 1, pro-
gramming of the LED2 Status register is enabled.
When LEDPE is cleared to 0, programming of the
LED2 register is disabled. Writes to this register will be
ignored.
Note: Bits 15-0 in this register are programmable
through the EEPROM PREAD operation.
Bit
31-16 RES
15
14
COLE
Name
LEDOUT
LEDPOL
Read/Write accessible. RCVE is
cleared by H_RESET and is not
affected by S_RESET or setting
the STOP bit.
Read/Write accessible. COLE is
cleared by H_RESET and is not
affected by S_RESET or setting
the STOP bit.
The logical value of the LEDOUT
status signal is determined by the
settings of the individual Status
Enable bits of the LED register
(bits 8 and 6-0).
This bit is read only; writes have
no effect. LEDOUT is unaffected
by H_RESET, S_RESET, or
STOP.
this bit is set, a value of 1 is
passed to the LEDOUT bit in this
register when there is collision
activity on the network.
zeros and read as undefined.
This bit indicates the current
(non-stretched) value of the LED
output pin. A value of 1 in this bit
indicates that the OR of the en-
abled signals is true.
the value 0, the LED pin will be
driven to a LOW level whenever
the OR of the enabled signals is
true. The LED pin will be disabled
Collision Status Enable. When
Description
Reserved locations. Written as
LED Polarity. When this bit has
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