stryd_one Posted June 22, 2003 Report Share Posted June 22, 2003 Hey guys,I know that the 18F chip can run at up to 10MIPS (I had to check that on the datsheet first heh)...I'm wondering about how much of that each of the MIOS functions will take....How much room do we have to work with here? For example, is the MB64SEQ (or any MIOS app) using up most of that speed already, or is there lots of processing power left over?Thanks all! Quote Link to comment Share on other sites More sharing options...
TK. Posted June 22, 2003 Report Share Posted June 22, 2003 The main target during the implementation was to make the drivers as fast as possible to have enough performance free for the applications. I measured the execution time of every critical routine like the shift register driver, the analog pin and MIDI handler with a scope and fought for every clock cycle :)It's hard to say how much MIOS really takes, as most drivers are scalable. Example: you can decrease the update frequency of the SRIO driver if you think that 100 uS/1 ms (=10%) performance loss is too much. With an update cycle of 10 ms (which is already fairly good for buttons, but not for rotary encoders), the load is only 1%.You can also decrease the number of shift register, for example to 4. In this case the driver only takes about 25 uS, makes 2.5% system load (1 mS update cycle) cause by the SRIO driver per millisecond...However, I already thought about a profiler which allows to measure the performance of system tasks and applications, but currently my priorities are on other tasks ;-)Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
TK. Posted June 22, 2003 Report Share Posted June 22, 2003 Here some application related numbers: The MIDIbox SID is currently the most complex application, especially because of the "software synth" engine for LFOs, Envelopes and Pitch. The update cycle of this synth is 800 uS, the PIC16F implementation takes about 500-600 uS, the PIC18F application about 200 uSMIDIbox Sequencer: the PIC16F implementation takes about 250 uS for every MIDI clock (@140 BPM the period of a MIDI clock is 17.8 mS). PIC18F: not implemented yet, but very relaxedBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
stryd_one Posted June 22, 2003 Author Report Share Posted June 22, 2003 Holy cow that's fast! :DWell I guess all my concerns about speed just went clearly out the window!Thanks heaps for the info TK, and once again, great work! Seriously, you do a fantastic job man, I really hope they appreciate your talent and hard work, at your paying job! I'm wishing a nice fat payrise on you right now :) Quote Link to comment Share on other sites More sharing options...
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