7.7.2 LPC Link 2 feedback

[lpcware]

Content originally posted in LPCWare by emh203 on Wed Apr 15 08:23:51 MST 2015
Whatever was done to connections to the LPClink-2 made things 500% better.


1.)   My application to a LPC4357 is an order of magnitude faster! I am very happy about this./
2.)   In 7.4. and previous versions there was a 50% change that I would get a Flash write error (or something else) on subsequent downloads.    This problem seems to have been fixed.    The debugger connection seems to terminate well.


The bad news is that the new version of GCC seems to have broken some code, particularly in sharing tasks across cores... trying to narrow down what the issue but some working code in 7.4 went to non working in 7.7.2

[lpcware]

Content originally posted in LPCWare by lpcxpresso-support on Wed Apr 15 09:11:47 MST 2015
Glad to hear that you like the improved download speeds  :bigsmile:

With regards to timing, what optimization level are you compiling at? Certainly with -Os, where code size is the primary objective, a slight slow down with some code is certainly a possibility as the optimizations carried out are tweaked between releases.

Generally, if you want better performance, switch to -O2 (or maybe even -O3).

http://www.lpcware.com/content/faq/lpcxpresso/compiler-optimization

Regards,
LPCXpresso Support

[lpcware]

Content originally posted in LPCWare by emh203 on Wed Apr 15 08:30:44 MST 2015
Ok... the problem turned out to be some new race conditions that I didn't expect.   I had some code that was not properly doing a MUTEX between the 2 cores.     I have a dual core graphics system that was rendering really bad stuff....   It turned out to be a simple fix.    It appears that the news version of GCC cause some some timing critical code to exectute at a different rate (looks to be a tad slower but need to investigate more).

Implementing some proper MUTEX's was the solution.


Either way,  the speed boost in the downloads/debug in 7.7.2 is much appreciated!