
Agere Systems Inc.
155
Data Sheet
July 2001
T8302 Internet Protocol Telephone
Advanced RISC Machine (
ARM
)
12 Ethernet 10/100 PHY(s)
(continued)
12.5.14 MR21 RXER Counter
12.5.15 MR28 Device-Specific Register 1 (Status Register) Bit Description
Table 139. MR21 RXER Counter
8-Bit, 16-Bit Mode Select
Bit 0 is the only bit that can be written to and it selects the operating mode of this register. Setting bit 0 specifies
16-bit or 8-bit counter mode and the indicated register map shown below is used.
Bit #
Name
Type
0
MCWO
W
16-bit, 8-bit counter mode.
If 1, the register is put in an 8-bit counter mode.
If 0, the register is put in a 16-bit counter mode.
This bit is reset to 0 and can’t be read (write only).
16-Bit Mode, Read-Only (Bit 0 written to 0)
Description
15:0
MC16
R
16-bit counter mode. When in 16-bit counter mode (
MCWO
= 0), these bits main-
tain a count of
RXER
s.
This bit is reset on a read operation.
8-Bit Mode, Read-Only (Bit 0 written to 1)
Disconnect events count. When in 8-bit mode (
MCWO
= 1), these bits contain a
count of disconnect events, (link unstable 6).
This bit is reset on a read operation.
False error count. When in 8-bit mode (
MCWO
= 1), these bits contain a count of
false error events.
This bit is reset on a read operation.
8-bit counter mode.
When in 8-bit counter mode (
MCWO
= 1), these bits maintain
a count of
RXER
s.
This bit is reset on a read operation.
15:12
CDE
R
11:8
CFER
R
7:0
MC8
R
Table 140. MR28 Device-Specific Register 1 (Status Register) Bit Description
Bit #
15:9
8
Name
RSVD
BAD_FRM
Type
R
R/LH*
Description
Reserved.
Read as 0.
Bad frame.
If this bit is a 1, it indicates that a packet has been received with-
out an
SFD
. This bit is latching high and will only clear after it has been read
or the device has been reset.
This bit is only valid in 10 Mbits/s mode.
Code violation.
When this bit is a 1, it indicates that a Manchester code vio-
lation has occurred.
Reserved.
Disconnect. If this bit is a 1, it indicates a disconnect. This bit will latch high
until read.
7
CODE
R/LH*
6
5
RSVD
DISCON
R
R/LH*
This bit is only valid in 100 Mbits/s mode.
Unlocked.
Indicates that the TX scrambler lost lock. This bit will latch high
until read.
4
UNLOCKED
R/LH*
This bit is only valid in 100 Mbits/s mode.
* LH = latched high.