LPC55s16 seems to fit my need I have questions

[sam_m]

So I came across this part because it has SW security.  I got here because of the Raspberry Pi Pico, I tinkered and made some stuff with it.  Now I want to use this device as the main and the Pico in support.  The Pico is setup to be simple to "execute" grab a USB cable and write some python.  Alot of the primitives are taken care of for interfaces and gpio.

Pico has one of these, another Pico can be made to be a Probe.  Is this possible?  Pico only use CLK and DIO, ground. Pico have USB as their main interface the SWD is extra goodness and not super necessary but helpful.  

If I get the MCU link and not a dev board, can I just hook the SWD pins to pins and debug?  Meaning I make my own board and provide the interface as the device seems to very easily stand alone.  What are the necessary pins?  

Is in MCU link the most likely way I can program an uninitialized device?  I cannot use any of the current interfaces?  I know there is some type of ROM that may have primordial flashing routines, as it is mentioned a UART interface can.  I haven't looked hard for the SW user guide for the device which may answer some of this.

If I use the IDE and USB instead will anything happen(my guess is no as Pico has that boot as USB flash drive and a way to load a file that will allow interaction with python or c or whatever.)?  

I did create an IDE for what I thought I would need as a bare board, but first thought I might by a dev board and then decided MCU link might be enough.

So the general question is, if I plop the device on a board and provide some pins/connections can I make it work with the IDE and some interface without the need for the dev board for my "training"?

[sam_m]

hey 

this is super helpful!  I actually had the third document.

from what i gather looking at the user manual for the part i can rely on SWD interface to begin a project in the software domain,  and eventually graduate it to say usb input of application code. but that is not necessary?  i can do all load and debug thru swd near term?  including setting up secure code methods?  (challenge and response and all that)

i then should use your MCU link for easiest best results?  (it is not expensive enough to create other problems with some other method, like I had suggested with Pico probe) I have it's UM as well.

There is no mention of the benefits of SWO but I gather there is and I planned to use it.

All of these help me establish a base line for the design as for now I just have it mocked up for my application in schematic tools.  It is a super dense thing but the datasheet is only about half the information as all of the above and other things are needed to start feeling secure in the design particulars.  I think it is not obvious from the web site how to piece things together. 

The device UM11295.pdf has been very useful.

But this reply is reasonably fast and reassuring!

thanks

[Julián_AragónM · Accepted solution]

Hi @sam_m,

Yes, the MCU Link should be enough for your needs by utilizing SWD. If you have any other doubts about documentation or guidelines, don't hesitate to ask.

Best regards, Julian

[sam_m]

Ok, sorry for the double check but in the UM11295 for the device is section 51.6.1 and while describing explicitly what happens does sound a little worrisome when a person has no experience with this part.  However I am very comfortable that the MCU-link handles all of this easily, I assume.  

I also assume that the MCU-link can establish SWO functionality as well.

I very likely will just design this part in on my circuit and not get the dev board, so I need to be comfortable with this vital method for code development.  The dev board may not be this "low of a state" so it will not provide the verification of the functions.

[Julián_AragónM]

Hi @sam_m,

MCU Link is enough to program the stand-alone CPU. If you need recommendations for debugging the CPU you will find this post useful for necessary pins: Design Considerations for Debug - NXP Community.

You can base your design on the hardware recommendation guidelines of the 55s16 in the application note and the schematics in its page:

• LPCXpresso55S16 Development Board | NXP Semiconductors
• Hardware Design Guidelines for LPC55(S)xx Microcontrollers (nxp.com)

I hope you find this useful.

Best regards, Julian