disketto Posted March 8, 2015 Report Share Posted March 8, 2015 Hi all, i just built an LPC 1769 based core box. It looks to me that there is no precompiled software to set up a Midibox SID directly from the LPC based core to the SID module. I am missing the place where i can get it or there's actually no software for this configuration ? If there is no precompiled software, there is some code where i can start from that fits the LPC micro ? What would be different from having the PIC based core controlling the SID unity ? Thankz, Vito Quote Link to comment Share on other sites More sharing options...
Shuriken Posted March 8, 2015 Report Share Posted March 8, 2015 As far as i know it's still PIC based. SVN does seem to contain some code, not sure how functional it is: http://svnmios.midibox.org/listing.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Fsynthesizers%2Fmidibox_sid_v3%2F Quote Link to comment Share on other sites More sharing options...
TK. Posted March 8, 2015 Report Share Posted March 8, 2015 MIDIbox SID is only available for PICs. A MIOS32 based solution would still need the PICs to interface with the SID chips, and since this is too complicated for typical users, I haven't continued with the migration. Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
disketto Posted March 9, 2015 Author Report Share Posted March 9, 2015 Hi Thorsten, why the MIOS32 based solution still needs the PICs to interface with the SID ? There is some matter about frequency or other things related to hardware ? Could you shed some light on that aspect ? Thanks, Vito Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted March 9, 2015 Report Share Posted March 9, 2015 Hi Vito, as far as i recall Thorstens arguments, the last time he was asked, he said, that there is no real benefit in moving up to a more modern core, as the SIDs can only accept a moderate register update speed - so basically, all the bases are covered with the PICs... development would be a major effort and there may be other low-hanging-fruit goals (aka other projects) in the limited devtime available... but this is all hearsay :-). The great thing about MIDIbox is, that everybody can step in and develop to his/her hearts desire, it is all documented, you could give it a try! Many greets, Peter 1 Quote Link to comment Share on other sites More sharing options...
disketto Posted March 9, 2015 Author Report Share Posted March 9, 2015 (edited) Hi Hawkeye, yes, i could imagine that the new core is over powered more than a SID module would need. But this is more a development need i have. I mean, i wanted, from the start, to develop my own control software and the LPC based core gave me more possibilities than the PIC based core, so i went for the LPC. At the moment i don't have a PIC based core, so i'd be happy to know the issues that are coming from the different clock frequency etc., and if it is possible to adapt the frequency of the LPC to work with the SID module. Thankz, Vito Edited March 9, 2015 by disketto Quote Link to comment Share on other sites More sharing options...
TK. Posted March 15, 2015 Report Share Posted March 15, 2015 The SID chip is clocked at 1 MHz, register write accesses have to be synchronized to this clock to prevent data loss, so that typically 2..3 clock cycles will be consumed to ensure that the write operation took place. During this time a PIC can only execute 30 instructions. A LPC1769 would execute more than 300 instructions during this time, and it shouldn't do anything else (or it has to service the write operations with a high-prio timer, which is another story). This results into a significant performance loss, and therefore the direct access doesn't make much sense. Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
disketto Posted March 19, 2015 Author Report Share Posted March 19, 2015 Thanks Thorsten, this is what i needed to know. Quote Link to comment Share on other sites More sharing options...
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