Topics

1

µTasker general / Serial Loader Timout - back to Application

« on: January 22, 2021, 06:28:07 AM »

I have everything working with the MSD-device serial loader but have one remaining issue.  The application is a full function battery monitor *inside* a line of high capacity lithium batteries (for marine and auto use).  Since the system is inside a sealed battery, there is no way to recycle power to the system as it is started at the battery factory and runs forever from there.  The concern is that a user or technician can get the system into the serial loader and not have a way to recover.

There is a membrane button switch assembly on the battery to restart the system via a serial connection (among othe things) and if the user holds a specific key while the start-up is in process, the serial loader executes (via FORCE_BOOT).  Once in the serial loader. there is no way to return to the application since the serial port no longer exists.

I am looking for a way to have the serial loader timeout and return to the application.  I could enable the SREC serial loader in addition to the MSD-device but don't know how to use that to get back to the applicaiont firmware. The concern here is that while the serial loader menu  would come up, the user would connect to the system with a PC *after* the menu was sent. I was thinking of how to use the watchdog timer but the timout would have to be maybe 30 seconds but I don't see how to do that.

Any advice on this problem is appreciated!

Thanks
Al

2

µTasker general / Jump to Serial Loader from Within Application code

« on: January 19, 2021, 12:31:21 AM »

What is the best way to do this?  I am using the MSD device serial loader.

Basically, I need to start the serial loader from a PC application that is sending a command over serial.  I want that command to execute the jump to the serial loader.  Everything works fine using a switch held during power up but I am looking for a programatic way to invoke the serial loader.


Thanks
Al

3

NXP^TM M522XX, KINETIS and i.MX RT / Serial Loader and EEPROM

« on: January 18, 2021, 08:09:15 PM »

I have the MSD serial loader working with a custom NXP MK20DX256 board (same processor as on a Teensy 3.1 and 3.2).  I have searched but cannot find how to prevent the serial loader from overwriting the processor EEPROM. 

I did find these lines in app_hw_kinetis.h but am unsure how to use them (or even if they are appropriate).

#define KINETIS_FLASH_CONFIGURATION_EEPROM_PROT        0xff
#define KINETIS_FLASH_CONFIGURATION_DATAFLASH_PROT     0xff

Is this the way to do it and if so what do I set the values to?