11-20
MCF5272 User’s Manual
Programming Model
MII_SPEED as a function of system clock frequency.
11.5.9 FIFO Receive Bound Register (R_BOUND)
R_BOUND is a read-only register used to determine the upper address boundary of the
FIFO RAM. Drivers can use this value, along with the registers R_FSTART and
X_FSTART, to appropriately divide the available FIFO RAM between the transmit and
receive data paths. The value in this register must be added to MBAR + 0x800 to determine
the absolute address.
Table 11-16. describes the R_BOUND fields.
11.5.10 FIFO Receive Start Register (R_FSTART)
The R_FSTART register, Figure 11-13, is programmed by the user to indicate the starting
address of the receive FIFO. R_FSTART marks the boundary between the transmit and
Table 11-15. Programming Examples for MII_SPEED Register
System Clock Frequency
[MII_SPEED]
E_MDC frequency
25 MHz
0x3
2.08 MHz
33 MHz
0x4
2.06 MHz
50 MHz
0x5
2.5 MHz
66 MHz
0x7
2.36 MHz
31
16
Field
—
Reset
0000_0000_0000_0000
R/W
Read only
15
11
10
2
1
0
Field
—
R-BOUND
—
Reset
0000_0
110_0000_00
00
R/W
Read only
Addr
MBAR + 0x884
Figure 11-12. FIFO Receive Bound Register (R_BOUND)
Table 11-16. R_BOUND Field Descriptions
Bits
Name
Description
31–11
—
Reserved, should be cleared.
10–2
R_BOUND
End of FIFO RAM. This field contains the ending address of the FIFO RAM, exclusive.
1–0
—
Reserved, should be cleared.
Summary of Contents for DigitalDNA ColdFire MCF5272
Page 1: ...MCF5272UM D Rev 0 02 2001 MCF5272 ColdFire Integrated Microprocessor User s Manual ...
Page 38: ...xxxviii MCF5272 User s Manual TABLES Table Number Title Page Number ...
Page 58: ...1 10 MCF5272 User s Manual MCF5272 Specific Features ...
Page 90: ...2 42 MCF5272 User s Manual Exception Processing Overview ...
Page 96: ...3 6 MCF5272 User s Manual MAC Instruction Execution Timings ...
Page 158: ...5 46 MCF5272 User s Manual Motorola Recommended BDM Pinout ...
Page 184: ...7 12 MCF5272 User s Manual Interrupt Controller Registers ...
Page 338: ...13 44 MCF5272 User s Manual Application Examples ...
Page 414: ...18 6 MCF5272 User s Manual PWM Programming Model ...
Page 452: ...19 38 MCF5272 User s Manual Power Supply Pins ...
Page 482: ...20 30 MCF5272 User s Manual Reset Operation ...
Page 492: ...21 10 MCF5272 User s Manual Non IEEE 1149 1 Operation ...