d2k Posted August 30, 2003 Report Share Posted August 30, 2003 Hey...So, I started a conversion on an old commadore 5octave keyboard i bought for peanuts to use as a bog standard midi controller kb with velocity sensitvity based on the project on this site: http://homepage.ntlworld.com/derek.johnson/I've sucessfully adapted the key's to form switches on the top and bottom rails and have breadboarded the pcbs which were quick to do. Now i need to burn the PIC (uses the 16F877 as in mbhp), the .zip file for the project (http://homepage.ntlworld.com/derek.johnson/velokbd.zip) contains an .asm file which i kinda thought I could load in a new project in mplab, build a new hex file and then burn that to the pic via icprog. Is that correct? I get errors msgs when it builds the hex file (even tho it does it) and then when i load the hex file in icprog i get more msg about bytes being swapped or summin :/ The Pic did burn tho...I was thinking however - could this code in the asm file be implemented in MIOS sumway? the IC's it uses to decode the switches before sending to the PIC are some 74HC138s - could I make up a special din module that uses these?BestDan Quote Link to comment Share on other sites More sharing options...
TK. Posted September 2, 2003 Report Share Posted September 2, 2003 Hi Dan,these are warning messages. "BUILD SUCCEEDED" means that the file has been assembled successfully.Message[302] can be disabled with following line in the assembler code: ERRORLEVEL -302 The IC-Prog message "The file does not contain any configuration information!"can be ignored, just disable this check somewhere in the options menuBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
d2k Posted September 3, 2003 Author Report Share Posted September 3, 2003 Thanks T...that has put my mind at rest now :)D'ya think a MIOS port of this app is doable? i'm assuming I could include more features - or perhaps it'd be best to use this as is and use a sep core module for any further processing...CheersDan Quote Link to comment Share on other sites More sharing options...
TK. Posted September 3, 2003 Report Share Posted September 3, 2003 No idea - I don't own such a keyboard and therefore don't have experiences which performance is really required...Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
d2k Posted September 30, 2003 Author Report Share Posted September 30, 2003 okay, so this project seems a bit of a no-no...:/I made up a pcb and converted the keys, but i'm gettin no midi out of it whatsoever :(. I'm sure the problem is in the asm file and the way i've gone about gettin it burnt to the PIC. I've tried emailing the fella but the email link on the site is returning msgs :/ - looks like he gave up on it n all then....So, i'm left with a nice commadore 5 octave keyboard with the key's converted so they function as switches which hit 1 of 2 bus bars when struck. Same principle as in this image:These then are connected to this (think din/dout modules):My thinking now is, can MIOS step in and rescue this project? It'd be a nice1, and a good project for the new MB portal...:)Best...Dan Quote Link to comment Share on other sites More sharing options...
DriftZ Posted September 30, 2003 Report Share Posted September 30, 2003 Ofcourse MIOS can rescue this thing, MIOS can do about anything imagineable (in the MIDI world) :) Quote Link to comment Share on other sites More sharing options...
d2k Posted October 10, 2003 Author Report Share Posted October 10, 2003 okay, good news...:)So, I have it like each key acting as a switch on 2 buss bars (NO and NC). With nothing pressed the keys all lie on the top bar and connect to the bottom bar when struck...How would the key contacts be treated in mios compared to the NO/NC contacts?I guess we could even have velocity sensitivity by using some kinda counter ye?CheersDan Quote Link to comment Share on other sites More sharing options...
d2k Posted February 23, 2004 Author Report Share Posted February 23, 2004 Hi...So getting back to this...how does this sound:61 Din inputs (for the keys)2 Dout outputs for the top and bottom rails (NO/NC)Start state: Top DOUT = 0, Bottom = 1. Then: Clock in all DINs. Which ever are set to 0 are sitting at the top. Next: Set top =1, bottom = 0. Then: Clock in all the DINS. Which ever are set to 0 are fully pressed. Any key that read 1 on both passes was moving at the time. We time clock up a timer for each moving key - and repeat the process...we can then see which keys are pressed, and how long then took to get from top to bottom...making sense?BestDan Quote Link to comment Share on other sites More sharing options...
TK. Posted February 24, 2004 Report Share Posted February 24, 2004 Hi Dan,yes, this makes sense.Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
d2k Posted February 24, 2004 Author Report Share Posted February 24, 2004 Hey T...thanks for the thumbs up :)...do u see any big probs doin this with mios over the original 16f project from that site? ie, calculating velocity values when say more then 5 keys are pressed...CheersDan Quote Link to comment Share on other sites More sharing options...
TK. Posted February 24, 2004 Report Share Posted February 24, 2004 No - but I would use serial shift registers due to the re-usability.But just wait for 2-3 weeks... I'm planning to provide a (tested) keyscan algorithm for a 5 octave keyboard. Its a MIOS based replacement for an old Polykobol synth of a friend. It will just only require one 74HC595, one 74HC165 and 60 diodesIt won't support velocity (since this keyboard only has single contacts), but this is something which you could add and test with your equipment. The velocity feature will require one additional 74HC165Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
d2k Posted February 24, 2004 Author Report Share Posted February 24, 2004 Hey T...But just wait for 2-3 weeks... I'm planning to provide a (tested) keyscan algorithm for a 5 octave keyboard. Its a MIOS based replacement for an old Polykobol synth of a friend. Â It will just only require one 74HC595, one 74HC165 and 60 diodesIntersting :D I'm in no rush for this one so will wait to peep ur methods neways :)It won't support velocity (since this keyboard only has single contacts), but this is something which you could add and test with your equipment. The velocity feature will require one additional 74HC165Cool! I'll def try the velocity version!Cheers T!Dan Quote Link to comment Share on other sites More sharing options...
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