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KL17x Fresh Chip, First Boot - Questions

Question asked by Rodrigo N. Hernandez on Nov 7, 2016
Latest reply on Nov 10, 2016 by Fan Yang

Hello there,


I'm in the task of laying down a fresh KL17 chip in a minimal PCB to start trying it out and start development(hardware/software). I'm used to the 8bit micros world and actually having a big time with chip's datasheet and user manual, trying to understand what it takes to be able to start. I have some questions/confirmations I would like to clarify to avoid trouble, or damaging/bricking the chip. Also to confirm if my expectations are correct:


1- User manual states that default reset clock for core/system clock is 8 MHz from IRC8M. So, initially, I don't need a external crystal to make it work and communicate using the bootloader, that's right?

2- Datasheet states that chip came with a pre loaded bootloader from the factory. The part identification numbers/letters doesn't let me know what bootloader version is. I will be able to make a first contact using the actual tools from download section in case it's some old version?

3- Considering is a new chip I guess all flash memory is uninitialized with 0xFF, that's all BCA values will be "1". The first configuration field bootloader is the magic number (that must be 'kcfg'). By the other hand is stated that "For uninitialized flash, the Kinetis Bootloader uses a predefined default configuration", so I can expect it will just set the magic number right in the first reset sequence? Later on if I perform a entire flash erase this default configuration sequence will be triggered again?

4- I don't know what are these default configurations but I expect values on BCA being 1 for what I read on user manual. That's, all peripherals will be activated/clocked by default, that's right?

5- There's anything like bricking the device? Or it's always some possibility to reset the device? From the 8bit micros I'm used to use a high voltage programmer to reset the chip if any #### happens.

6- For what I understand from bootloader user docs is that I will be able to make contact using the tools and the PC as host, directly from UART. My intention is interfacing UART directly to PC COM port using a TTL<->RS232 level converter. Is correct understanding that it will work this way?


Sorry about the amount of questions or if there are stupid ones, any clue that could me lead on the right direction is greatly appreciated!