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MPC555
/
MPC556
SYSTEM CONFIGURATION AND PROTECTION
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
6-3
6.1 System Configuration
The SIU allows the user to configure the system according to the particular require-
ments. The functions include control of show cycle operation, pin multiplexing, and in-
ternal memory map location. System configuration also includes a register containing
part and mask number constants to identify the part in software.
System configuration registers include the system configuration register (SIUMCR),
the internal memory mapping register (IMMR). Refer to
for register diagrams and bit descriptions.
6.1.1 USIU Pins Multiplexing
Some of the functions defined in the various sections of the SIU (external bus inter-
face, memory controller, and general-purpose I/O) share pins.
summarizes
how the pin functions of these multiplexed pins are assigned.
.
6.1.2 Memory Mapping
The MPC555 / MPC556 internal memory space can be assigned to one of eight loca-
tions.
The internal memory map is organized as a single 4-Mbyte block. The user can assign
this block to one of eight locations by programming the ISB field in the internal memory
Table 6-1 USIU Pins Multiplexing Control
Pin Name
Multiplexing Controlled By:
IRQ0/SGPIOC0
IRQ1/RSV/SGPIOC1
IRQ2/CR/SGPIOC2/MTS
IRQ3/KR/RETRY/SGPIOC3
IRQ4/AT2/SGPIOC4
IRQ5/SGPIOC5/MODCK1
IRQ6/MODCK2
IRQ7/MODCK3
At Power-on reset: MODCK[1:3]
Otherwise: programmed in SIUMCR
(See
6.13.1.1 SIU Module Configuration Register
SGPIOC6/FRZ/PTR
SGPIOC7/IRQ_OUT/LWP0
BG/VF0/LWP1
BR/VF1/IWP2
BB/VF2/IWP3
IWP[0:1]/VFLS[0:1]
BI/STS
WE(0:3)/BE(0:3)/AT(0:3)
TDI/DSDI
TCK/DSCK
TDO/DSDO
Programmed in the SIUMCR and via the hard reset configuration.
(See
6.13.1.1 SIU Module Configuration Register
7.5.2 Hard Reset Configuration Word
DATA[0:31]/SGPIOD[0:31]
ADDR[8:31]/SGPIOA[8:31]
Programmed in SIUMCR and hard reset configuration.
(See
6.13.1.1 SIU Module Configuration Register
7.5.2 Hard Reset Configuration Word
.)
RSTCONF/TEXP
At Power-on reset: RSTCONF
Otherwise: programmed in SIUMCR.
(See
6.13.1.1 SIU Module Configuration Register
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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