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MPC8349E-mITX-GP Reference Design Platform User’s Guide, Rev. 0
Freescale Semiconductor
11
Preliminary—Subject to Change Without Notice
MPC8349E-mITX-GP Board
The DS1339 RTC is connected to I
2
C with address 0x68. The software running on PowerPC core can read
or write to the RTC through the I2C2 interface.
1.2.8
10/100/1000 BaseT Interface
On the MPC8349E-mITX-GP board, GMII mode is used on TSEC1 , which is connected to the on-board
10/100/1000 PHY (VSC8201). The TSEC I/O voltage is set to 3.3 V. The GMII (1000 BaseT) is a source
synchronous bus. For a transmit bus connection, it is synchronous to GTX_CLK from the TSEC module.
The receive bus connection is synchronous to RX_CLK generated from the PHY device. When the speed
is 10/100 BaseT (MII), both transmit and receive clocks are generated by the VSC8201 PHY device. The
MPC8349E MII management interface is connected to the VSC8201 only.
Figure 7
shows the connection
between the MPC8349E TSEC1 to the VSC8201.
Table 4. PCF8574A (U10) Bit Descriptions
PCF8574A
(U10) bit[0..7]
Name
Read/Write
Description
0
REV1
Read only, write
has no effect
Board revision number
REV[0:1] definition
00: revision 0.0
01: revision 0.1
10: revision 1.0
11: reserved
1
REV0
2
Reserved
Read only, write
has no effect
Reserved for future use
3
Reserved
Read only, write
has no effect
Reserved
4
MPCI_CLKRUN
Read/Write
Reserved
5
PCI_M66EN
Read only, write
has no effect
PCI M66EN Signal
0: PCI M66EN signal is low, indicates the PCI cards on PCI slot is
not 66 MHz capable
1: PCI M66EN signal is high, indicates the PCI cards on PCI slot is
66 MHz capable
6
BOOT0
Read only, write
has no effect
Used to determine which Flash is used for boot Flash
0: Reserved
1: Flash 1 (U7) is the boot Flash
7
Not used
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