UART BOOTING FOR TM4C123G

Sravan Janamaddi

I am trying to update firmware through UART and without using LM FlashProgrammer. I am able to send the sync sequence {0x55,0x55}for auto baud and follwed by COMMAND_PING.

Now this is my problem after sending COMMAND_GET_STATUS I am able to receive packet from the Bootloader , but when I send next command it is sending me the same previous packet all the time.

So I continued without observing it but after sending the firmware in between I am getting negative acknowlgment and when I read flash contents they aren't the updated one it shows flash is empty not even small data had been dumped.

please mention if there is any mistake in command procedure

over 9 years ago

0 Markel Robregado over 9 years ago

Guru 85695 points

Hi,

Do you know about the boot_serial example program? Does what you want to do is the same as what boot_serial does?

- kel

0 Sravan Janamaddi over 9 years ago in reply to Markel Robregado

Intellectual 525 points

Thanks for response

Actually I want to update the firmware through UART when flash is empty, that too without using LM Flash Programmer.

I went through boot_serial example, but it is not what I want .

I want to update when flash is empty.

0 Markel Robregado over 9 years ago in reply to Sravan Janamaddi

Guru 85695 points

Hi,

The usual is to have a bootloader like boot_serial loaded first.

Try to load working example program using Serial Interface of LM Flash Programmer. I do not know if that will work. I have not tried to do that.

- kel

0 Sravan Janamaddi over 9 years ago in reply to Markel Robregado

Intellectual 525 points

Hi,

No my wish is to keep flash empty(all 0xFFFFFFFF's). Then I write my own program to flash through uart without using LM Flash Programmer.

I need to create an interface which exatly work as LM Flash Programmer in my case.

See, when FLASH is empty and using Serial interface in LM Flash Programmer, I am able to dump my firmware.But I dont want LM flashProgrammer I need to write my own software to dump the firmware.

I am able to initialize UART and able to set baud rate by sending {0x55,0x55} .After sending

COMMAND_PING
COMMAND_DOWNLOAD

I got acknowledgments even but when I am sending firmware through COMMAND_DATA there I am facing problem and it is sending negative acknowledgment but my checksum value is correct all the time.

0 Markel Robregado over 9 years ago in reply to Sravan Janamaddi

Guru 85695 points

Hi,

I think codes in this folder location might help. I think there is also a document for that.

"\tools\sflash"

- kel

0 Sravan Janamaddi over 9 years ago in reply to Markel Robregado

Intellectual 525 points

Thank you I wil refer in the document

0 Sravan Janamaddi over 9 years ago in reply to Sravan Janamaddi

Intellectual 525 points

Refering to LM flasher document has solved the problem we have to send 0x55 or 0xAA before sending any data through UART for a virgin board

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UART BOOTING FOR TM4C123G