Boot ROMMCF5253 Reference Manual, Rev. 119-2 Freescale SemiconductorThis mode supports booting from the following:• I2 C connected slave device• SPI connected slave device• Hard Disk Drive (IDE)In slave mode, the MCF5253 will wait for communication from a controlling MCU and store the code itreceives in RAM. It executes this code after receiving an execute command. The controlling MCU mustcontrol the data transfer and handle error recovery if required.This mode supports booting from the following:• I2 C connected master device• UART connected master19.2 Boot ROM Operation19.2.1 Initialization19.2.1.1 Boot ROM Memory mapbootrom:origin = 0x00000000, length = 0x00002000mbar:origin = 0xb0000000, length = 0x10000000mbar2:origin = 0xc0000000, length = 0x40000000sram1:origin = 0x10000000, length = 0x00010000sram0:origin = 0x10010000, length = 0x0001000019.2.1.2 Internal SRAM usageThe boot ROM data resides in the upper range of the internal SRAM.The SRAM allocation is as follows:0x1001FC90 – 0x1001FF13Bootloader uninitialized data (HDD) (644 bytes)0x1001FF14 – 0x1001FF3FBootloader uninitialized data (Serial) (44 bytes)0x1001FF40 – 0x1001FFFFBootloader Stack (192 bytes)NOTEThe HDD data space is available for use when booting from a serial device.If the user routine exceeds the assigned stack allocation, then it would bemore appropriate for the user to define their own stack space, especially ifthe user routine returns to the bootloader.Initialization sequence_Boot:move.w #0x2700,SRmove.l #VECTOR_TABLE,d0movec d0,VBR; /* Invalidate the cache and disable it */move.l #0x01000000,d0movec d0,cacr
