The silicon shortage is still going on. While the NXP Kinetis KE devices might not be my first choice, they still seem to be available, in at least in lower quantities. This has been recognized by others, as I’m getting more and more questions and requests for the KE and KV family. This is why I un-dusted my old FRDM-KE02Z to be used with the latest MCUXpresso SDK and IDE.
And in case you want to use that board or device with semihosting, I have you covered.
One of the most important aspects of the ‘IoT’ world is having a secure communication. Running MQTT on lwip (see “MQTT with lwip and NXP FRDM-K64F Board“) is no exception. Despite of the popularity of MQTT and lwip, I have not been able to find an example using a secure TLS connection over raw/native lwip TCP :-(. Could it be that such an example exists, and I have not found it? Or that someone implemented it, but has not published it? Only what I have found on the internet are many others asking for the same kind of thing “running MQTT on lwip with TLS”, but there was no answer? So I have to answer my question, which seems to be a good thing anyway: I can learn new things the hard way :-).
Block diagram MQTT Application with TLS using lwip
The world is changing, and the say is “change is good” :-). In the software and API world, change very often means that a change results into something broken. So I had battled with semihosting working on the NXP Kinetis parts, only to find out that it does not work any more with using the latest version 2.0. The semihosting output e.g. with P&E debug connection remains empty: