/tilted/

More information please... Which make of core board? What type of LCD? Thanks.

Hiya. voltage drop is only one concern here. you also need to worry yourself with cable inductance and capacitance, both of which act as a kind of 'low pass filter' for your LCD control signal. They will limit the current and voltage slew rates respectively, and this in turn means potentially lost data. The cable limitations can be overcome to an extent by driving the cable using extra hardware in the form of transmitter/reciever buffers. Regarding the hot-plug issue, I'm not sure, but I think the LCD is initialised by the core at start-up. This coulld perhaps be overcome by using a spare D-sub pin to act as a plug detect pin, forcing the core to init/reset the LCD when the plug is inserted.

Hiya. I guess I should clarify some things here. I don't think I should've said that the core couldn't do anything else but output a DMX stream. I guess I should've said that having a SEQ with DMX out would mean having a SEQ with somewhat decreased SEQ functionality, for the sake of giving it DMX out... A core would be capable of outputting DMX in addition to other tasks, but the DMX would take a fair bit of functionality away from the PIC itself. The IIC idea sounds like a winner, but remember you don't neccesarily need to use a 16F88. Perhaps a 18F22xx or 23xx might help. These seem to have 28 pins, but they also have 512 bytes of delicious RAM to slam away at. This would keep your core free for tasks such as calculating timed fades, splitting 16 bit numbers to multiple channels, running any display/interface etc... while the slaves handle the patch and the output timing.

hey, don't underestimate the power of the 6502!!

Actually truth told, it's done in terms of layout. All we need to do is: - Make the boards and verify that they actually work. - Write the app. Then it becomes DIY... What has taken extra long so far, is me doing the layouts from scratch about 6 times. A few times became corrupted files, then there was a switch to kicad, then a couple of re-designs.

Excellent news! - Soon we will all be cheering and eating Kangaroo... mwuh ha ha haaaaaaah!

Progress: sorta. I've finalised the prototype files for the inputs, outputs, and the matrix itself. All three of these boards now exist as multi-layer Gerber files, ready to send to the board-house. Movement: not really. I just can't throw a lot of money at this at the moment. I made a bit of a pact with myself to (and I realise this sounds extraordinary on these pages) stop adding to my 'to do list', until after I've finished my monster LC box. I (as many others) seem to just keep adding things to my list, without dedicating any more time to actually completing anything. I guess I just need to prove to myself that I can actually dedicate time to something specific. Don't give up, this project has not vaporised, but it has sort of slowed a little, 'til I can afford to prototype a board.

If you're happy with the two options (on/off) method, then the dpdt switch should be do-able. You are also right that a multi-postion switch with different resistors is more or less equivalent to a pot. You could perhaps experiment with, say, a toggle switch and a momentary switch, wired in 3-way configuration: (please ignore the use of words like "mains", "live" etc...) If you had one toggle and one pushbutton momentary, then the toggle is used to set the pushbutton as either "momentary on", or "momentary off", ie two modes for feedback: "button=feedback on", and "button=feedback off". This would allow for a little bit of tweaking, or at least rapid changes...

Greetings from Collingwood! Let it be known that I have no football affiliation whatsoever. P.S.: I get a lot of good stuff from eBay. It can be a goldmine for interesting hardware (emphasis on gold...) ;D

lh: of course. I was talking more about problems due to "operator error", not so much the "build something foolproof, and nature supplies a greater fool" effect. Impossible is really not the word here. Perhaps it's more like "If you're not trying to break it, you won't..." s1: I've always been somewhat adverse to supplying the outside world with any signal if it can be helped. My point is that if your gonna give the outside world any part of your circuit, then giving it a grounded chassis is definitely your best and safest option for most applications. (It is certainly better than giving it Sclk, or Mains Active for example... ;D ) Of course, there are always exceptions... for example if the end user is likely to be exposed to high voltage supplies while using the equipment (some industrial applications) then you'll want your chassis to float, else it will potentially supply a handy return path for said high voltage... Some audio folk prefer their equipment to be un-grounded, and this is achievable, but should always be done from the early design stages, not as an after-market modification (unless you are a skilled engineer). I've lost count of the times I've been asked to cut the earth pin off some piece of vintage gear. (for vintage, read "old!")... I've made a number of enemies that way, as I always refuse. In terms of inadvertently applying power to a sheilded case, this is why power supplies have fuses. ;D

Having a metallic chassis gives you a type of Faraday cage, which will help to keep wide band noise out of your gear. (not just RFI, but pretty much the whole spectrum) - ever wondered why your mobile phone stops working when you get into a lift(/elevator)?. Connecting your chassis to ground increases the effect greatly. Phantom power (as of course just one example) has been designed to be impossible to short out outside of lab conditions. - Think about it. All the inputs to your console, which could ever carry phantom power, are female sockets at the desk. All devices which use phantom have a male socket. This means that the free end of a phantom powered cable will always be a female end. You can't touch the phantom pins while they are active. Of course, you could try extra hard and get a male to male cable...

Ah, memories. ;D

Re the Nord photo... what if each button pair had two rows of LEDs? perhaps one row for 'octave' and another row for 'note'... In this case, you could probably do the whole thing with 2 rows of 8 LEDs. -I'd suggest the 'note' row be duo LEDs, so you can have sharps, too... This is kinda not software wishlist stuff anymore. This could perhaps be integrated into an external controller.

Very nice.

No chips here just yet. Mind you, I do live all the way up here:

Good to hear. Well done.

Possibly, possibly not. How are you connecting the LCDs to the core? is there any way you might have got that bit wrong? You have determined by changing the LCD out, that the issue was not the Core, but could be either of the LCD; or the LCD cabling. This does not immediately mean the LCD is broken, it may still be a wiring issue between the Core and LCD. A short / bad wiring will occasionally show as garbled characters on the LCD. see also here: http://www.midibox.org/forum/index.php/topic,11632

The LCD derives its contrast voltage using a pot (P2) connected across +5V and GND (Vdd and Vss). The wiper of the pot is then connected to the Vo Contrast pin on your LCD. Normally LCD contrast voltages are in the range 2V - 3.5V. To get -2.6v, build the circuit linked by Ping, and wire your pot (P2) across -5V and GND. The wiper of the pot connects to Vo as normal. Be sure to disconnect the +5V terminal of your pot before connecting it to -5V, to avoid smoke...

Tasty. ...and the award for most captivating new animated avatar goes to: casius!! -kinda reminds me of david firth. :D

Nice! Top work DW.

I think it's likely that the term a doctor uses to describe you would be largely based on how much of a prick you are to them, or how you present yourself to them. For example, if you turn up stinking of booze, they'll probably be less sympathetic toward you than normal. Whether you are a chronic disease suffererer or not, I dare say that a civil tongue on the part of the patient will spare you from many of these jibes. Unfortunately medical practitioners tend to see people when they are at their worst (or at least, their whiniest...) I think it's only natural for a doc to throw around the odd acronym if someone gives them the shits. This doesn't excuse terms like "GLM", or the DBI... These are assumptions and stereotypes. However, much as it might offend, I think DW is dead-on with the coping mechanism description. I like some of them, I think the TEETH one is pretty good, and "handbag positive"...

**snikker** lucky she turns the light off! the next bit is really hard to animate!

Mmmmmmmm... boards... Thanks Sepp.

I likey!! I always felt that the biggest downfall of the RC-20 (XL) was the lack of MIDI sync. Of course the big mamma does it (apparently)... what is it, the RC-50 or sth. But that sucker is like 3 times as much as the RC-20... Cool idea.

*ahem* cross post. very useful, though. ;D