Freescale Semiconductor MPC5565, Reference Manual

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Boot Assist Module (BAM)
MPC5565 Microcontroller Reference Manual, Rev. 1.0
15-8 Freescale Semiconductor
This allows code, written to run from internal flash memory, to execute from external memory.
15.3.2.2.2 Single Bus Master
External boot with no arbitration mode is used for single-master systems where the MCU is the only bus
master, therefore no arbitration of the external bus is necessary. Refer to
Section 15.3.2.2.3, “Configure
the EBI for External Boot—Single Master with no Arbitration .”
The boot modes are specified by the BOOTCFG[0:1] value. Refer to the following sections for more
information:
Section 12.5.5.2, “Arbitration with No Arb Pins (Master/Slave only) ”
Section 12.4.2.10, “Bus Operation in External Master Mode ”
Section 12.5.5, “Dual-MCU Operation with Reduced Pinout MCUs ” to implemen,t a system with
master and slave peripherals for a device with no arbitration pins.
15.3.2.2.3 Configure the EBI for External Boot—Single Master with no Arbitration
The BAM program configures:
• Chip select CS[0] as a 16-bit port starting at base address 0x2000_0000 with:
— no burst
— 15 wait states
— 8 MB
• EBI for no external master (clears EXTM bit)
• Enables the EBI for normal operation
• Configures the following EBI signals:
— ADDR[8:31]
— DATA[0:15]
— WE[0]
— OE
— TS
— CS[0]
Table 15-5. MMU Configuration for External Boot Mode
TLB
Entry
Region Attributes
Logical Base
Address
Physical Base
Address
Size
1 Internal flash
memory
• Cache enabled
• Not guarded
• Big endian
• Global PID 0x0000_0000 0x2000_0000 16 MB
2 EBI • Cache enabled
• Not guarded
• Big endian
• Global PID 0x2000_0000 0x2000_0000 16 MB