TMS320LF2407_08 Datasheet, PDF (34/116 Pages) Texas Instruments – DSP CONTROLLERS

TMS320LF2407, TMS320LF2406, TMS320LF2402
DSP CONTROLLERS
SPRS094I − APRIL 1999 − REVISED SEPTEMBER 2003
boot ROM
Boot ROM is a 256-word ROM memory mapped in program space 0000−00FF. This ROM will be enabled if the
BOOT_EN pin is low during reset. The BOOT_EN bit (bit 3 of the SCSR2 register) will be set to 0 if the BOOT_EN
pin is low at reset. Boot ROM can also be enabled by writing 0 to the SCSR2.3 bit and disabled by writing 1 to
this bit.
The boot ROM has a generic bootloader to transfer code through SCI or SPI ports. The incoming code should
disable the BOOT_ROM bit by writing 1 to bit 3 of the SCSR2 register, or else, the whole Flash array will not
be enabled.
The boot ROM code always sets the PLL to x4 option. If the boot ROM is used, the CLKIN value should not
exceed 7.5 MHz. Any CLKIN value greater than 7.5 MHz would force the DSP to run at speeds greater than
30 MHz, the maximum rated speed. Furthermore, when the bootloader is used, only specific values of CLKIN
would result in a baud-lock for the SCI. Refer to the TMS320LF/LC240x DSP Controllers Reference Guide:
System and Peripherals (literature number SPRU357) for more details about the bootloader operation.
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