AnsweredAssumed Answered

AN2295 Serial bootloader doesn't work on FRDM-KL25Z, why?

Question asked by Kai Liu on Aug 8, 2013
Latest reply on Aug 15, 2013 by Hui_Ma

I am evaluating AN2295 bootloader on FRDM-KL25Z.

 

After checking the source code, I found UART0(PTA1/PTA2) is used for bootloader, which is actually UART connects to OpenSDA on board. So I download the code into KL25Z128VLK4 on board and have a try.

 

Since the bootloader only works after POR, I have to unplug and reconnect it to USB. Then I run "win_hc08sprg" client program, select COM, load S19 file, click "Connect".

 

The connection always timeout.

 

Waiting for HC(S)08/ColdFire/Kinetis reset ACK (timeout: 0s)...

Error receiving reset ACK - TIMEOUT.

 

Or it reports receiving wrong character like 0x00.

 

received 0x00 (ignoring).

received 0x00 (ignoring).

received 0x00 (ignoring).

received 0x00 (ignoring).

received 0x00 Waiting for HC(S)08/ColdFire/Kinetis reset ACK (timeout: 0s)...

Error receiving reset ACK - TIMEOUT.

 

It seems USB VCP of OpenSDA takes quite a long time to work, maybe it requires more time? Or we have some issues on UART communication of bootloader?

 

Attachment is my revision for AN2295.

I tried to add LED as indicator, so far it doesn't work well. MCG/PORT/GPIO is processed, it still doesn't work.

And I tried to enableBootMode by POR as well as reset PIN , but it doesn't help either to enter bootloader mode.

Original Attachment has been moved to: Kinetis.zip

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