C6747 ROM Bootloader Requirements

Daisuke Maeda

Guru 20205 points

Other Parts Discussed in Thread: TMS320C6747

Below is described in SPRABB1C.

Memory Usage: The bootloader uses 16 KB of DSP L2 RAM starting from 0x11800000 for multiple
purposes. This memory should not be used by any initialized section of the user application.

Decompression Heap: When the compression option is used, the bootloader uses 64 KB of DSP L2
RAM starting from 0x11830000 to allocate heap for the decompression routine. This memory should
not be used by any initialized section of the user application.

NOTE: The compression option is only available for devices with the d800k001 ROM revision. See
the introduction for instructions to check your device’s ROM revision.

Using the TMS320C6747/45/43 Bootloader (Rev. C)
http://www.ti.com/lit/an/sprabb1c/sprabb1c.pdf
9 Boot Requirements, Constraints and Default Settings

Is my understanding below correct?

For the d800k003 and later ROM revision, the memory which is 64 KB of DSP L2 RAM starting from 0x11830000 is not used by the bootloader.
This memory can be used by any section of the user application.

Best regards,

Daisuke

over 13 years ago

0 Rahul Prabhu over 13 years ago

TI__Guru** 116170 points

Hi Daisuke,

Yes, your interpretation is correct. The compression option is available only in ROM revision 0xd800k001, and doesn`t exist in subsequent revisions so the 64KB of DSP L2 can be used by sections of application code. Please note that the compression option is not enabled by default even in the 0xd800k001 ROM and the boot loader will only use this region when the decompression option is selected during the AIS Generation with that version of the ROM.

Best Regards,

Rahul

0 Daisuke Maeda over 13 years ago in reply to Rahul Prabhu

Guru 20205 points

Hi Rahul,

Thank you for the reply.

Best regards,

Daisuke

0 Daisuke Maeda over 13 years ago in reply to Daisuke Maeda

Guru 20205 points

Hi Rahul,

Our customer saw the value in this memory changed every time after Warm Reset.

I know Internal memory is maintained through a warm reset.

Why did the value in this memory change?

Best regards,

Daisuke

0 Rahul Prabhu over 13 years ago in reply to Daisuke Maeda

TI__Guru** 116170 points

Daisuke,

Do they see the values in that section of the memory change to the same value every time they reset or do they change to different random values. What is the boot mode they have set the boot pins to and is there a boot image in that media that may be writing to that address?

Regards,

Rahul

0 Daisuke Maeda over 13 years ago in reply to Rahul Prabhu

Guru 20205 points

Hi Rahul,

Thank you for the reply.

They change to different random values.

HPI boot mode is used, therefore there is not a boot image.

Best regards,

Daisuke

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C6747 ROM Bootloader Requirements