Kinetis L: "conceptual" doubts.

Discussion created by EgleTeam on May 28, 2016
Latest reply on Jun 2, 2016 by EgleTeam



we are starting a project with a Kinetis L (MKL27Z256VFM4). This is our 3rd project with Kinetis: the previous two were very simple at hardware level (almost copy/paste from development boards). We use to work with PICs so many concepts of Kinetis are new to us.


I have two questions that probabby are very obvius but I don't know now:


1. Can I use a 16mhz crystal to get 48mhz for core and usb?. 8mhz crystals usually have a big encapsulate.


2. How can I access to a complete port of GPIOs?. I try to explain... we'd like to use eGUI in GPIO mode (the uC seleted doesn't have flexbus) so I guess we need to connect our frammebuffer in RAM to a complete port of GPIOs via DMA (space color is 8bpp). The problem is that I can't find how to do that in the reference manual. In fact I don't understand how the GPIOs are distributed since in the uC chosen, for example, have a PORTA that goes from PTA0-PTA5 to PTA18. I can find 8 GPIOs in a row...