Post by thread:[PIC] MPLAB C18 optimized printf. Was:{OT} Legal s

Changing tag because I think it entered the PIC domain. Just finished benchmarking my custom PIC18 'printf' against Microchip's original: Test code vas: unsigned long value = 1; while( 1 ) { printf( "%lu", value ); value *= 10; } int _user_putc( char c ) { return 0; } Please note that the function '_user_putc' was "neutralized" just to remove hardware times from the benchmark. We are testing just the mathematical portions of the process. Function "_user_putc" is what ultimately displays each character. Times for Microchip's original 'printf': value -> cycles 1 -> 2104 10 -> 3756 100 -> 5440 1,000 -> 7108 10,000 -> 8840 100,000 -> 10556 1,000,000 -> 12288 10,000,000 -> 14036 100,000,000 -> 15800 1,000,000,000 -> 17628 Times for my improved 'printf': value -> cycles 1 -> 1255 10 -> 1347 100 -> 1621 1,000 -> 1895 10,000 -> 2229 100,000 -> 2503 1,000,000 -> 2777 10,000,000 -> 3111 100,000,000 -> 3385 1,000,000,000 -> 3659 I think my routine is worth sharing but I'm afraid of doing this without knowing the legal implications, that's why I posted the original question. Regards, Isaac Em 15/2/2012 15:27, Isaac Marino Bavaresco escreveu: {Quote hidden}> Dear all, > > > Many should know that Microchip's MPLAB C18 compiler comes with full > source code of its libraries, even the lite and eval versions. > > I made many improvements to said files for my own use. My question is: > how could I share my improvements with others without breaching > Microchip's copyright? > > I have thought that perhaps I can publish the diffs between my versions > and Microchip's. Diff files bear a minimum of the original source code > just to contextualize where the changes are to be inserted. This way, by > using my diffs alone nobody can retrieve Microchip's source code, he/she > would need to have already the original source code to apply the patches > against. > > What do you think? > > > Some files I rewrote from scratch. Those I think are safe to share. > > > Best regards, > > Isaac >

Isaac, The most definitive answer is to contact Microchip directly. I have had a lot of dealings with Microchip over the years and you will get a clear definitive answer. The process could take a few days. Walter.. Isaac Marino Bavaresco wrote: {Quote hidden}> Changing tag because I think it entered the PIC domain. > > Just finished benchmarking my custom PIC18 'printf' against Microchip's > original: > > Test code vas: > > unsigned long value = 1; > while( 1 ) > { > printf( "%lu", value ); > value *= 10; > } > > int _user_putc( char c ) > { > return 0; > } > > Please note that the function '_user_putc' was "neutralized" just to > remove hardware times from the benchmark. We are testing just the > mathematical portions of the process. Function "_user_putc" is what > ultimately displays each character. > > Times for Microchip's original 'printf': > > value -> cycles > 1 -> 2104 > 10 -> 3756 > 100 -> 5440 > 1,000 -> 7108 > 10,000 -> 8840 > 100,000 -> 10556 > 1,000,000 -> 12288 > 10,000,000 -> 14036 > 100,000,000 -> 15800 > 1,000,000,000 -> 17628 > > Times for my improved 'printf': > > value -> cycles > 1 -> 1255 > 10 -> 1347 > 100 -> 1621 > 1,000 -> 1895 > 10,000 -> 2229 > 100,000 -> 2503 > 1,000,000 -> 2777 > 10,000,000 -> 3111 > 100,000,000 -> 3385 > 1,000,000,000 -> 3659 > > I think my routine is worth sharing but I'm afraid of doing this without > knowing the legal implications, that's why I posted the original question.. > > Regards, > > Isaac > > Em 15/2/2012 15:27, Isaac Marino Bavaresco escreveu: > > Dear all, > > > > > > Many should know that Microchip's MPLAB C18 compiler comes with full > > source code of its libraries, even the lite and eval versions. > > > > I made many improvements to said files for my own use. My question is: > > how could I share my improvements with others without breaching > > Microchip's copyright? > > > > I have thought that perhaps I can publish the diffs between my versions > > and Microchip's. Diff files bear a minimum of the original source code > > just to contextualize where the changes are to be inserted. This way, by > > using my diffs alone nobody can retrieve Microchip's source code, he/she > > would need to have already the original source code to apply the patches > > against. > > > > What do you think? > > > > > > Some files I rewrote from scratch. Those I think are safe to share. > > > > > > Best regards, > > > > Isaac > > > >

> Isaac, > > The most definitive answer is to contact Microchip directly. I have had a lot of > dealings with Microchip over the years and you will get a clear definitive answer. > > The process could take a few days. > > Walter.. They may even want to include your code in the release. I note that in the C30 release, I think it is, there are credits to individuals for library code. This may be only because it comes as part of the GNU compiler, but may be for other reasons. -- Scanned by iCritical.

On Thu, 16 Feb 2012, spam_OUTalan.b.pearceTakeThisOuTstfc.ac.uk wrote: >> The most definitive answer is to contact Microchip directly. I have had a lot of >> dealings with Microchip over the years and you will get a clear definitive answer. >> > They may even want to include your code in the release. All indications are that C18 has no future, so that seems unlikely. I can't imagine Microchip devoting the time to test and release new library code for C18. -- John W. Temples, II