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MPC555
/
MPC556
BURST BUFFER
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
4-20
4.6 Burst Buffer Programming Model
The BBC and IMPU module configuration registers are MPC555 / MPC556 special-
purpose registers (SPRs). They are programmed with the MPC555 / MPC556
mtspr/
mfspr
instructions.
All the registers can be accessed in supervisor mode only. The processor generates
an exception internally if an attempt is made to access the registers from user mode.
The following 32-bit registers contain the starting address and the size of the region.
There is one register for each region.
The following registers hold the attributes of the corresponding regions and of the de-
fault region. Each of the four MI_RAx registers contains access permission attributes.
The MI_GRA (global region attribute) register contains two additional bits to enable
each of the MI_RBAx registers.
The BBC holds only one register, the BBC module configuration register (BBCMCR).
Table 4-2 Region Base Address Registers RBA[0:1]
Register Name
Address
(Decimal)
ub_addr[18:27]
(hex)
MI_RBA[0]
784
0x2180
MI_RBA[1]
785
0x2380
MI_RBA[2]
786
0x2580
MI_RBA[3]
787
0x2780
Table 4-3 Region Attributes Registers
Register Name
Address
(Decimal)
ub_addr [18:27]
(Hex)
MI_RA[0]
816
0x2190
MI_RA[1]
817
0x2390
MI_RA[2]
818
0x2590
MI_RA[3]
818
0x2790
MI_GRA
528
0x2100
Table 4-4 BBC Module Configuration Register
Register name
Addr
(Decimal)
ub_addr [0:31]
(Hex)
BBCMCR
560
0x2110
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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