Some questions about “tower_bootloader“

[wangb]

I  have  two  questions.

1.After I modified the program according to my hardware, I used JTAG to download the “tower_bootloader“ into the chip and used kinetisflashtool to connect to com port. The connection failed.What could be causing the connection to fail?

My modifications include, 1, turning uart1 uarto0.    2,  configuring Rx,Tx pins to use on my hardware.and 3, adding the configuration of RN485.

2.When I use the debug mode in Keil for debugging, the situation appears in the picture.The configuration of the JTAG is set up according to the configuration that it ran successfully before.Could there be any other reason for this?

[jingpan]

Hi Wang,

1. I have a article shows how to change UART port in bootloader. Please refer to this link https://community.nxp.com/t5/Kinetis-Microcontrollers/How-to-change-UART-port-on-MCU-Bootloader2-0-0...

2. It seems debug is failed after execute SystemInit(). Please check in it, mainly focus on watchdog, clock setting.

Regards,

Jing

[wangb]

hi Jing,

thank you very much!

As shown in the figure, I removed the WDOG part of the configuration, but in debug mode, the error phenomenon remains the same as before.What else can I change? 

I also tried to close the" jump_to_application()", but nothing changed.Can you help me see what might be wrong with the clock set?

[jingpan]

Hi,

Please disable watchdog in debug mode. Watchdog is enabled after reset. If the problem is caused by SystemInit(), you can trace into this function to check where is the problem.

Regards,

Jing