AM79C978A AMD [Advanced Micro Devices], AM79C978A Datasheet - Page 193

• Manufacturer Part Number: AM79C978A
• Description: Single-Chip 1/10 Mbps PCI Home Networking Controller
• Manufacturer: AMD [Advanced Micro Devices]

HPR25: HomePNA PHY Noise Statistics (Register 25)
HPR26: HomePNA PHY Event Status (Register 26)
Hex
Hex
1A
19
Address
Address
15:10
Bits
15:8
Bits
7:0
7:4
9
8
3
2
1
0
PHY_NOISE_STAT
Peak Level
PHY_Event Status
RxPCOM
TxPCOM
Reserved
Packet Received
Packet Transmitted
Remote Command Received
Remote Command Sent
Noise Level
Reserved
Table 71. HPR25: HomePNA PHY Noise Statistics (Register 25)
Table 72. HPR26: HomePNA PHY Event Status (Register 26)
Mnemonic
Mnemonic
This is the digital value of the
SLICE_LVL_NOISE output. It is effectively
a measure of the noise level on the wire and
tracks noise by counting the number of
false triggers of the NOISE comparator in
an 800 ms window. When auto-adaptation
is enabled (bit 5 of the PHY_Control
Register is false), this register is updated
with the current NOISE count every 50 ns.
When adaptation is disabled, this register
may be written to and is used to generate
both the SLICE_LVL_NOISE and
SLICE_LVL_DATA signals.
This is a measurement of the peak level of
the last valid (non-collision) AID received.
Indicates a valid RxPCOM. An access to
the RxCOM MSB Register 18 will clear
this bit.
Indicates a valid TxPCOM. Any access to
the TxCOM registers (Registers 20 and 21)
will clear this bit.
Reads will produce undefined results.
Status is cleared by writing a 0.
Status is cleared by writing a 0.
A valid remote command was received.
Status is cleared by writing a 0.
A remote command has been sent.
Status is cleared by writing a 0.
Am79C978A
Description
Description
Read/
Read/
Write
Write
R/W
R/W
R/W
R/W
R/W
R/W
R
R
R
R
Default
Default
Hex
Hex
D0
03
0
0
0
0
0
0
0
Reset
Reset
Soft
Soft
S0
03
0
0
0
0
0
0
0
193