topic Re: Multi Drop in Serial Wire Debug in LPCXpresso IDE

Multi Drop in Serial Wire Debug

lpcware — Wed, 15 Jun 2016 21:25:14 GMT

Content originally posted in LPCWare by badri89 on Fri Sep 21 23:24:57 MST 2012
I have 8 lpc1115 processors in chain. Is it possible to use a single SWD connection and do debugging? I am using LPCXpresso with LPC-Link. If so, how to connect my SWD and SCLK of all the processors?

I have read this link:
http://support.code-red-tech.com/CodeRedWiki/MultipleJtagDevices

But no info on SWD is given. Kindly help

Re: Multi Drop in Serial Wire Debug

lpcware — Wed, 15 Jun 2016 21:25:15 GMT

Content originally posted in LPCWare by CodeRedSupport on Sat Sep 22 01:01:05 MST 2012
Multi-drop SWD is not possible in these devices. AFAIK, there are no multi-drop SWD devices available from any MCU vendor (the spec from ARM is *very* recent). Sorry

Re: Multi Drop in Serial Wire Debug

lpcware — Wed, 15 Jun 2016 21:25:15 GMT

Content originally posted in LPCWare by vasanth on Sat Sep 22 01:18:46 MST 2012
What about LPC4300?
Does LPCXpresso support dual core debugging available in this part?

Re: Multi Drop in Serial Wire Debug

sambriggs — Wed, 08 Mar 2017 18:05:32 GMT

I would like to ask if this continues to be the case? My company is planning on using the QN9020 BLE microcontroller and I would like to know if it supports multi-drop?

Re: Multi Drop in Serial Wire Debug

thefallguy — Thu, 09 Mar 2017 19:39:41 GMT

Multi-drop SWD is not supported in standard Cortex-M0, M3 and M4 parts. According to this ARM article:
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka16814.html

The chip vendor (i.e NXP) needs to license (and therefore implement in silicon) an additional component. AFAIK, NXP has not...