/tilted/ Posted April 20, 2008 Report Share Posted April 20, 2008 Oscillators have 4 pins.Crystals have 2 pins.The clock divider (which I'm assuming is what the flip-flop is for) needs an oscillator input.You can get a crystal to run as an oscillator, but you'll also need two ceramic caps, a resistor and an inverter.Check these links.http://en.wikipedia.org/wiki/Pierce_oscillatorhttp://www.midibox.org/dokuwiki/crystals_and_oscillators Quote Link to comment Share on other sites More sharing options...
nILS Posted April 20, 2008 Author Report Share Posted April 20, 2008 Thanks tilted for answering that question ;Dalso, the last post you did with code in it, i believe on page 3 of this thread, is that the final app or at least one that will work?That's far from being the final version :-) It's more of a sketch really - this project is still pretty early in the development state, and I'm waiting for a friend to etch the boards for me (hence the slow progress). If anyone built a pokey board, lemme know and I'll make sure you'll get a test-app that at lees spits out some tones.edit: Latest schem is attached so you actually know what to build :-)mbPokey_0,4.pdfmbPokey_0,4.pdf Quote Link to comment Share on other sites More sharing options...
buhler Posted April 20, 2008 Report Share Posted April 20, 2008 Oscillators have 4 pins.Crystals have 2 pins.The clock divider (which I'm assuming is what the flip-flop is for) needs an oscillator input.You can get a crystal to run as an oscillator, but you'll also need two ceramic caps, a resistor and an inverter.Check these links.http://en.wikipedia.org/wiki/Pierce_oscillatorhttp://www.midibox.org/dokuwiki/crystals_and_oscillatorsah. i see. i guess i'm going to be a newb for longer than i thought!!! thanks for the links! i am curious though, i usually get my components from mouser, what abbreviation is the 4 pin oscillator? i know that i have to stay away from SMD like the plague. i learned my lesson on that one! thanks again.[edit] is there a formula for figuring out what values the resistor and capacitors need to be in a Pierce Oscillator? Quote Link to comment Share on other sites More sharing options...
buhler Posted April 24, 2008 Report Share Posted April 24, 2008 is this the oscillator i want? http://www.mouser.com/Search/ProductDetail.aspx?qs=2FvjVE%2fO2XABym18KDCGoA%3d%3d i read that the pierce oscillator was a little unreliable so i thought i'd try to find the one i needed at mouser. [edit] also, i can't remember what IC you are using on the core. is it the 18F4685? Quote Link to comment Share on other sites More sharing options...
/tilted/ Posted April 25, 2008 Report Share Posted April 25, 2008 that looks like the one you want.I'm not sure where the "pierce oscillator is unreliable" bit comes from, I'm interested to find this out.In fact, the 4-pin oscillator is AFAIK a crystal and pierce oscillator in a sheilded case. This explains why it is a little bigger than just the crystal. About enough to house a resistor, a couple of caps and a couple of transistors... Quote Link to comment Share on other sites More sharing options...
buhler Posted April 25, 2008 Report Share Posted April 25, 2008 i more or less meant that there was more room for error on my part... ::) in fact, you are correct about the 4 pin oscillator being a pierce oscillator. i just couldn't figure out what resistors and caps i would need... ;D Quote Link to comment Share on other sites More sharing options...
buhler Posted April 25, 2008 Report Share Posted April 25, 2008 i'm about to order a core kit from smash... i still need to know what IC i should use, is it the 18F4685?? thanks. Quote Link to comment Share on other sites More sharing options...
nILS Posted April 28, 2008 Author Report Share Posted April 28, 2008 Any PIC supported by MIOS should work. I'm using the 18F452 at the moment, so that might be a good choice ;-) Make sure to order a DIN and a DOUT kit as well - you might need some controls after all. Quote Link to comment Share on other sites More sharing options...
stryd_one Posted April 28, 2008 Report Share Posted April 28, 2008 Any PIC supported by MIOS should work. I'm using the 18F452 at the moment, so that might be a good choice ;-) Make sure to order a DIN and a DOUT kit as well - you might need some controls after all.If you're on a 452, then the 452 or 4620 should work, but the 4685 may have issues. Quote Link to comment Share on other sites More sharing options...
buhler Posted April 28, 2008 Report Share Posted April 28, 2008 thanks for the relpies dudes! ;D i'm working on two POKEY boards right now, so i'll hopefully have them done this week. i'll be bugging you for some POKEY programming action soon nILS! :D Quote Link to comment Share on other sites More sharing options...
buhler Posted May 2, 2008 Report Share Posted May 2, 2008 hey nILS. i finally got all the parts i need to build the POKEY module BUT i still have a newb question to ask. i consider myself a fairly descent reader of schematics but what does this section of the schematic mean (see attached)? i understand that there are 6 100nf capacitors, that's obvious, but what are the other connections? Quote Link to comment Share on other sites More sharing options...
bugfight Posted May 2, 2008 Report Share Posted May 2, 2008 power pins for the ics Quote Link to comment Share on other sites More sharing options...
buhler Posted May 2, 2008 Report Share Posted May 2, 2008 power pins for the icsaaahh. just a condensed version? i just haven't come across something like this yet... thanks bugfight! say, do you think you might be able to give me a slap? foona's been hogging them lately... ;D[edit] these newb questions are gonna keep comin' i guess... new question: do the capacitors correspond to the VCC and GND of each IC and the Oscillator? i.e. 6 caps corresponding to 5 IC's and an oscillator. i'm a little confused by the schematics in this area. sorry once it's cleared up, i should be ok... i understand that they are all in parallel but it seems like that wouldn't really work out correctly if i were to actually build it exactly that way. to me, it makes more sense to have each VCC and GND of each IC connected to a corresponding cap. correct me if i'm wrong. Quote Link to comment Share on other sites More sharing options...
bugfight Posted May 2, 2008 Report Share Posted May 2, 2008 no slap for you!the caps should go "as close as possible" to the power supply pins on the ic's Quote Link to comment Share on other sites More sharing options...
nILS Posted May 2, 2008 Author Report Share Posted May 2, 2008 whee! Bugfight is sacrificing his last tweaker posts to answer "my" questions. Sweet. He must really like me.[me=nILS Podewski]hugs bugfight[/me]edit: Thanks for ze pointing out zed I had a germlishing in ze post, bugfight! Quote Link to comment Share on other sites More sharing options...
buhler Posted May 2, 2008 Report Share Posted May 2, 2008 no slap for you!the caps should go "as close as possible" to the power supply pins on the ic'sthanks bugfight... i really hope someday we can be friends. ;D i know i'll get a slap at some point! Quote Link to comment Share on other sites More sharing options...
buhler Posted May 3, 2008 Report Share Posted May 3, 2008 Well... here's Veroboarded POKEY module number 1! i guess this would be considered the newb way but i don't have access to a PCB etcher nor do i know how to use Eagle or something like it. i actually have been having a lot of fun veroboarding my projects lately! ;D now i'm building POKEY module number 2 and scrounging up funds for a Core module + parts and another LCD, DIN and DOUT. let me know what you think thus far! thanks to nILS for doing the hard part of the work for me!! ;D[edit] i know it's ugly but there is some semblance to the layout of nILS' etched prototype... Quote Link to comment Share on other sites More sharing options...
nILS Posted May 3, 2008 Author Report Share Posted May 3, 2008 Looking good :-) Got any sounds yet? Quote Link to comment Share on other sites More sharing options...
stryd_one Posted May 3, 2008 Report Share Posted May 3, 2008 i guess this would be considered the newb way but i don't have access to a PCB etcher nor do i know how to use Eagle or something like it. Then I'm a newb too :) Good work man! I think vero is a perfectly respectable way to do it... Quote Link to comment Share on other sites More sharing options...
buhler Posted May 3, 2008 Report Share Posted May 3, 2008 Looking good :-) Got any sounds yet?not yet. i need a core and a POKEY taylored app. how far along on the programming are you? i'd like to help as much as i can but i fear that the most i can help is testing whatever you do... ::)Then I'm a newb too :) Good work man! I think vero is a perfectly respectable way to do it...thanks stryd! you always make me feel a little less "newb." :D Quote Link to comment Share on other sites More sharing options...
/tilted/ Posted May 4, 2008 Report Share Posted May 4, 2008 i guess this would be considered the newb way...I'd say that doing a prototype on veroboard is much more challenging than buying a board (or a kit) and assembling it.Well done. Quote Link to comment Share on other sites More sharing options...
nILS Posted May 4, 2008 Author Report Share Posted May 4, 2008 I've got a software version that basically let's you play notes and push values into the registers manually - I'll post that here as soon as I gert back home next weekend. Quote Link to comment Share on other sites More sharing options...
buhler Posted May 4, 2008 Report Share Posted May 4, 2008 I've got a software version that basically let's you play notes and push values into the registers manually - I'll post that here as soon as I gert back home next weekend.awesome!! maybe once i get a hold of that, you can point me in the right direction and i can help with the programming and get it running smoothly with a MIDI controller etc... whatever i can do!! ;D i'm totally open and excited to learn so i'll figure it out if you get me started![edit] what app/firmware is it based on?? SIDv1.7? i can try messing with it now if you have some sort of shell you are working from... Quote Link to comment Share on other sites More sharing options...
nILS Posted May 5, 2008 Author Report Share Posted May 5, 2008 At the moment it's based on the C skeleton which is most likely not gonna be the way to go, but it works really well for some basic testing. Quote Link to comment Share on other sites More sharing options...
buhler Posted May 5, 2008 Report Share Posted May 5, 2008 At the moment it's based on the C skeleton which is most likely not gonna be the way to go, but it works really well for some basic testing.okay. i'm just going to get very familiar with the POKEY. i'll read the datasheets, etc a few more times over so i can get a grasp on this chip. then maybe i'll be of more help. :) Quote Link to comment Share on other sites More sharing options...
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