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

[kai_liu]

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

[Hui_Ma]

Hi,

I am checking with this issue, I will be back when I could get any updated info.
Thank you for the patience.

B.R.
Ma Hui

[kai_liu]

Hi, Ma Hui,

Now I may need your help on AN2295 again! Now it stuck on downloading custom firmware.

I am sorry to bother you all the time.

Yours sincerely

Allan K Liu

[Hui_Ma]

Hi Kai,

I just add comments on your new thread  AN2295 again! Now it stuck on downloading custom firmware

Please check it and thank you for the attention.

B.R.

Ma Hui

[kai_liu · Accepted solution]

Hi, Ma Hui,

I have setup another thread regarding my issues on AN2295 on : Something wrong with AN2295 bootloader on FRDM-KL25Z for its reset behaviour

Up to now, I have summarized my issues and related solutions on that thread.  Please check it out. And I am working on a demo with modified icf for redirect vector and shift start point for user application.

Thanks for your support.

Allan K Liu