Jidis Posted March 1, 2005 Report Share Posted March 1, 2005 Hello,I've just finished the MTC (LED) circuit for a MIDIMon, and was wondering what to do about all the "LCD related" PIC pins. All I'm making it for is MTC and MIDI clock. I guess I won't be needing the push buttons either.Looks like I need the resistors on p2-10 regardless. Is there something in particular that needs to be done to the LCD pins (28-30,33-38) or do I leave them open? How about the other empty pins in the diagram? Also, should I ground the two filter pins (4&5) since all I want is time code?If Thorsten K. reads this--Just how bad off is the original 16F874/77 code for my purposes? I saw your mention of it being unreliable. I can socket the PIC and put in an order for the new chip, but I've already got two of the old ones.                         - Thanks for everything!George Quote Link to comment Share on other sites More sharing options...
TK. Posted March 2, 2005 Report Share Posted March 2, 2005 Hi George,The LCD port can be left open - the RBx pins of the PIC have internal pull-ups which ensure that MIOS will regognize that no LCD is connected properly (the LCD driver will be switched off after Time-Out).To the jumpers: most pins are output pins, don't clamp them - Just left them open! R2, R9 and R10 should be stuffed to avoid latch-up. The pins at J5 of the core module should either be clamped (if you are sure) or stuffed with the pull-ups to select the options.The 16F874 code is very bad concerning MTC, it was not processed correctly in all casesBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
Jidis Posted March 2, 2005 Author Report Share Posted March 2, 2005 Thorsten,Thanks! I'm not sure I'm looking at an up to date schematic. I've got 6 RB pins going to the LCD and 3 others from RD 5-7 (p28-30). Which ones are the R2,R9,R10 you refer to? And pins 2-10 of the PIC (RA0-5,RE0-2) all take a resistor to 5v, except the grounded filters at pins 4 and 5 (RA2,RA3). Does all that sound right? -Thanks Again!PS- How about MIDI clock with the old code (other than the 99 bar limit)? I mainly want to use a 16f to see if the unit is working. The 18f will take me a little while till I can put together a worthwhile digikey order. Also, the display board appears to be wired perfectly, despite the fact that I got 4 dual segment LEDs, the 3 shift registers and the 16 resistors on a single sided board measuring about 38mm x 115mm (1.5"x4.5"). Quote Link to comment Share on other sites More sharing options...
TK. Posted March 3, 2005 Report Share Posted March 3, 2005 Hi Jidis,I refer to the MBHP_CORE schematic for the PIC18F452, yes, your assumptions are correct.the 99bar limit does only exist in the old firmware. It also cannot handle with the song position pointer sent by some MIDI programsBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
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