ma3a.au

hey jorge, your screen (and the rest of your SID) look great!! very very cool. the reason i was (and still am) interested in an orange-backlit lcd was because i plan to build my SEQ into an old C64 case, so we must think alike ;) thanks for the pictures :) -duncan

g'day everybody. apart from building the SEQ (will start that in a month or two, when i have more time, and more experience with soldering :P) and modifying the magic delay code for my needs, there's one other thing i'd like to do with the MIDIbox project: build a MIDI to trigger interface. i'm not sure if someone else has already talked about this, or maybe even done it; i haven't been able to find any info in the forums. people seem to be more interested in making trigger to MIDI interfaces, but i'd like it the other way around :). the reason i'd like to build one is that it'd enable me to control, through MIDI, the older, cheaper drum machines with only simple modification (for each sound - and perhaps its accent - to be triggered when voltage is applied to an input; this is how the older drum machines' sequencers worked, anyway, so it's not hard at all), and also because it'd allow me to control home-built stuff...and lights and electric kettles etc, if i ever feel the need ;). anyway! i don't need analog control; just an "on" or "off" is fine (i.e. a quick voltage spike to let the trigger-input of the drum machine know it has to do something), so i'd be using DOUTX4 modules. what i envisage is: * 16 trigger-outs * five switches; ** the first switch will choose whether to take the each trigger's trigger from MIDI input from 16 consecutive notes on a particular channel (these notes will be more or less 'hard-wired'; not user-definable. i want to keep this simple!), or whether to take each trigger-out's trigger from any note on its corresponding MIDI channel (channel 1 triggers trigger-out 1, etc). sorry if i didn't word that very well. ** the last four switches will be to determine the MIDI channel number to take the input of notes from, if the first switch is set to take its input from 16 consecutive notes on one channel. if the first switch is set to take each trigger's input from its corresponding MIDI channel, then the four channel switches will have no effect. * in a rack-mount case it seems pretty simple to me, and i think i could program it, given some time. i'm not so sure about the hardware-side (specifically whether the voltage from the DOUT modules would be enough, or whether they'd have to be in a transistor setup to trigger larger voltages, and also what voltages would work with most drum machines etc while not damaging them - 5V?), so my questions are: * has this been done before by anyone, to spare me some effort..? * does anybody have any ideas how i could make this work (both on the hardware and software side; is there a particular route or method that i should take in writing the software?)? it'd be an incredibly useful device in my line of music/experimentation :) sorry this is fairly long and not written in a very interesting way. i look forward to your replies! :D -duncan

ahh yeh. and pre-128-sinclair spectrums would've been like that too, probably. that's not the sound of chip tunes, all the same..!

thanks, mobius :). yeh yeh i know what a reference is! i understand that's a good place to find the instruction set etc, *but* i was just wondering about a tutorial to see how program flow etc differs, as i only have experience with one brand of assembly, so i don't know how my current knowledge carries over. all the same, i'll take a look at those examples you linked to. thanks again :)! -duncan

hey everybody. i'm sorry if this should be easy to find, or has been covered before, but i have looked ???. i've experience with assembly, but only with 6502 assembly; none with PIC assembly. as such, i'd like to check out a tutorial or book or something that's relevant to programming the PIC18F452, though none seem to deal with it specifically (except for that embedded designs book, though i'd like to go for something a little more freely available at the moment, as i'm rather short on money :-\). tutorials regarding the PIC16F84 seem to be quite common - how relevant is it? i shall also, of course, check out the PIC18F452's datasheets. i'm also after some basic information on programming over MIOS (does it have routines to simplify interfacing to MIDI? is it an abstraction layer?), and also some information on how things like the DINX4 and DOUTX4 modules interface with the core module. is there documentation for this available at the ucapps site? thanks everybody :) -duncan PS - i spose i should ask, though i'd really rather go the assembly-route: there seems to be a bit more info regarding programming through MIOS in C - would this be a better option? i don't know C, but i've been interested in learning for a long time now. would programming for MIOS be a bad primer? :P

hey thanks jorge! sounds like an easy solution :). so no green tinge to it, and it's bright enough?

you have a pm, mr rabbit ;)

hey everybody. i'm lining up parts to use in my SEQ, and my heart's pretty set on using these keycaps ( - the "industrial" ones down the bottom, see picture here) so i don't have to write the button-functions on the front panel itself. i can't, however, find any switches to suit them; the connector-thing is a + shape (check out the pics in the link and you can see them ok). only switches with those connectors that i've seen are in my commodore 128D keyboard, and i don't really wanna take that apart :-\. does anybody know where i can get switches like this? thanks everybody :) PS - i spose while i'm at it i should ask my other parts-related question: are there any orange-backlit 2*40 LCD screens out there that can be used in the SEQ?

sorry i took so long to reply, but your help once again is very much appreciated, raphael :)! anyway, i might post this in a more appropriate forum-section, but i'm looking to read up on PIC assembly, and before jumping into a reference-guide, i'd like to check out PIC assembly program flow techniques etc, so i was hoping to check out a tutorial or something, but there are (of course) none focusing specifically on the PIC18F452, so the question is: which PICs have a similar instruction/feature set, that might have tutorials on the net? the PIC16F84 seems to have a lot about it on the net - how similar is this? thanks again :) -duncan

on what is perhaps a side-note, did the pokey do multi-pulse square waves? (like, being able to program the sequence of the square wave, eg 10010110 would become a wave that, on an oscilloscope, would look like -__-_--_ (0 is "down", 1 is "up)) if it didn't, what *did*? somebody fairly intelligent wrote that it was multi-pulse square waves that made early sound chips sound the way they do, but i haven't seen any that seem to do it yet ::)...

hey thanks tatapoum :D - just the answer i needed!

thanks for another response, raphael :). when i asked if the buttons were the same or different on various units that midiboxers have made, i mean the buttons themselves. not their style (be they round or square, normally-open or normally-closed); rather i mean the things they do. judging from what you've said about "button-functions", i'm guessing yes, but i'd like to make sure: does every SEQ have the same number of buttons, and do these buttons do the same thing from unit to unit? this is on the full control-surface, that is. thanks for all your help, raphael. i think i'm pretty much all set - now i just need some time ;D -duncan

g'day everybody. oberheim once made a product called the strummer, and MIDI note on/off information fed into it was analysed so that chords were "staggered" (as a guitar sounds - the notes in a chord on a guitar are really played one after the other as the guitarist strums). i'm not sure if i explained that too well, but hopefully everybody gets the idea. it did other things (such as more arpeggiator-like functions), but they're already covered by other MIDIbox devices. below are some quotes from the 'net of what it did, that i think would be good to replicate in a MIDIbox device: would it be possible to add these features into the existing Magic Delay device, or in a self-standing device? another simple MIDIbox that would be useful (at least to me..!) would be a device that splits sounds into separate channels, either through the keys that are being played (ranges; say A2-C5 output on channel 1, while D5-G6 output on channel 2), or through velocities (bleow a certain velocity outputs on channel 1; above that velocity outputs on channel 2), etc. i'm much more than willing to give these projects a go; i have experience with assembly programming (though not PIC programming - i can learn, though!), though my real hang-up is that i have no idea about MIDI. where can i learn about this? i remember googling around a while back, and not turning anything up. maybe i just can't search ;) let me know what you all think! -duncan

sorry :-[...i keep thinking up new questions as i read more about doing this. * should i buy just the PCBs from smash-tv, or the actual kits? i think if i bought them as kits i wouldn't have to program the PICs. is that correct? i've found the page on where-to-buy for australian midiboxers, though i'm not altogether confident about sourcing all the parts myself (i'll be fine with all the front-panel controls, though) - buying in my native country would certainly be cheaper, wouldn't it? * making the front-panel is the only thing i'm worried about: should i use that hole-board stuff (as most people do), or just mount things on to the front panel? what are the advantages/disadvantages of each? using the hole-board stuff (sorry..what's its real name? :$) looks much nicer, because the buttons and knobs are set back, but it would require me coordinating where i put things on the hole-board stuff and where i cut holes in my front-panel: i'm not good at that (or does anyone have any tips at doing that? i'm good at maths and measuring things, but awful at visual/artistic stuff). * on many of the finished SEQs i've seen, the button-layout is different - are the buttons they have the same, or different? sorry i have to ask this; i'm mildly dyslexic and am bad at matching things like that up. * a final, more light-hearted question: is this project easier than the MIDIbox SID? it seems to be, though - if my SEQ's successful - i'd like to build one, as it was my interest in C64- and SID-music that originally drew me to your site (i think i found it by accident, or was linked to it from another forum, at www.lemon64.com - i remember someone there was very unhappy about that picture of all the C64s cannibalised just for their SID chips!) anyway, thanks again, everybody (especially raphael :)) -duncan

thanks again, everybody :)! i found out the differences between the mobius sequencer and the SEQ, so i thought i'd post them here in case someone's searching for it on this forum one day (as i did before i asked): * the mobius is only one-track, and afaik it's still only one-track even if it's only sequencing a rhythm part. the SEQ, on the other hand, is 16-track, and if some of the tracks you're sequencing are just rhythm instruments (drums, etc), then you get more than 16 tracks; up to 48 tracks. big advantage! * the mobius has a "glide" function to allow it to slide between notes like the TB-303 does (though only when using CV-outs, i think: not using MIDI). afaik, the SEQ can't do this (though if you set the gate time of each note to max, and are sequencing a sound that has portamento, it might work. i'm not sure it will, though, and it's probably not as good as the real thing) * the mobius also has an "accent" function, once again like the TB-303. on the SEQ, though, you can individually program the velocity of each note in a sequence, so if you program the sounds on your synth right (to respond to higher/lower velocities), you could probably do a very good emulation with the SEQ. i don't think the mobius can program individual velocities like the SEQ can. * the mobius doesn't seem to have as nice a user-interface as the SEQ: the SEQ has two great big LCD screens, while the mobius has a single 4-ish digit LED screen. similarly, the SEQ has lots of encoders and lots of buttons, while the mobius only has a lot of buttons. encoders are nice :) * the mobius seems to be better for sequencing and interfacing with analog gear, as it incorporates a CV-out, and can be used as a CV-midi converter or vice-versa. i think that's just about it :)! other than that, they seem to do fairly similar things. if anyone has anything to add or correct, feel free to do so! -duncan