Ethernet Physical Transceiver (EPHY)
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
19-18
Freescale Semiconductor
19.3.3.9
Auto Negotiation Next Page Transmit
shows the contents of the A/N next page transmit register. The MI writes to this register if it
needs to exchange more information with the link partner. The PHY defaults to sending only a NULL
message page to the link partner unless the STA overrides the values in the register. Next pages are
transmitted until the link partner has no more pages to transmit and bit 7.15 has been cleared
by the STA.
Figure 19-14. Auto Negotiation Next Page Transmit Register
19.3.4
PHY-Specific Registers
PHY also contains a number of registers to set its internal mode of operation. These registers can be set
through the external management interface to determine capabilities such as speed, test-mode, circuit
bypass mode, interrupt setting, etc. The PHY register set includes registers 16 through 29. These registers
are not part of the MCU memory map.
MII Register Address: 0x07
Access: User read/write
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
NXTP
0
MSGP
ACK2
TGL
CODEFIELD
W
Reset
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
1
Table 19-14. Auto Negotiation Next Page Transmit Register Field Descriptions
Field
Description
15
NXTP
Next Page
1 Additional next pages follow
0 Last page to transmit
14
Reserved, should be cleared.
13
MSGP
Message Page
1 Message page
0 Unformatted page
12
ACK2
Acknowledge 2
ACK2 is used to indicate that the receiver is able to act on the information (or perform the task)
defined in the message.
1 Receiver is able to perform the task defined in the message
0 Receiver is unable to perform the task defined in the message
11
TGL
Toggle
1 Previous value of the transmitted link code word equalled 0
0 Previous value of the transmitted link code word equalled 1
10–0
CODEFIELD
Message/Unformatted Code Field
Message code field — Predefined code fields defined in IEEE 802.3u-1995 Annex 28C
Unformatted code field — Eleven bit field containing an arbitrary value
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:MCF52234CVM60,
MCF52235CVM60