Wilba

There appears to be a rectangular piece of glass with metal film around the edge, behind the LCD layer, and a 1mm gap between the two. It seems quite possible to add another few white LEDs to the other side, or insert some kind of diffusing semi-transparent sheet in this gap. I've only briefly tested this one at low brightness and it's not as bad as it looks in photos, maybe at maximum brightness the bright spot on the right edge will be more noticeable. Maybe I'll get another one to experiment with, and stick a few RGB LEDs on each end for a colour-blended look ;D

On closer inspection, these edge-lit displays just have three white SMD LEDs in parallel connected directly to the A and K pins on the right side, and these pins are connected directly to pins 15 and 16. There is no current-controlling circuitry as you would find in displays with LED arrays (components are missing from the PCB!). I'm surprised that they don't mention this in the datasheet. So the 60mA in the spec is just 3 x 20mA for each LED. With a 3.5v forward voltage, the voltage drop of a current limiting resistor would be 5v - 3.5v / 0.060 amps = 25 ohms. I didn't have one handy, but 5v through a 100ohm resistor lit up the backlight to what I assume was less than half brightness. By the way, these aren't white-on-blue, they're actually black-on-grey... a bit like this: I might not drive it so bright though... so it's still a grey background for that retro old-school LCD look ;D

email: info@albs.de

I don't think I explained enough what I think the problem is... In "TAKE 1", you probably burned each PIC with MIOS device ID 0x00, recompiled the setup_8580.asm with different DEFAULT_DEVICE_ID, but left AUTO_DEVICE_ID = 1, this meant DEFAULT_DEVICE_ID was ignored, and each PIC autoconfigured SID device from MIOS device ID, so all PICs were masters! Enabling "Link" meant all incoming MIDI messages were sent to the other PICs, and since they all were probably on the same MIDI channel, they all played the default patch on incoming note events, and when "CC" was enabled, you had some control over the other PICs, but patch loading is done via special SysEx messages with the SID device ID in the message, and the other PICs were ignoring them because they were all SID device ID = 0x00. Once each PIC has its own unique MIOS device ID (0x00-0x03), you should be able to upload the same setup_8580.hex (with AUTO_DEVICE_ID = 1) and everything should work. The fact that you got some sound out of the slave SIDs and could control some parameters means it's not a hardware problem at all, you've got your master PIC's Tx connected to all three slave PIC's Rx, and they're receiving it fine.

You should not need to change DEFAULT_DEVICE_ID. When AUTO_DEVICE_ID = 1 (the default) then the firmware uses the MIOS device ID (ID burned into PIC with bootloader) to determine the SID device ID, so MIOS device ID 0x00 will be the master, 0x01-0x03 will be the slaves. There's no reason to change how this works, just burn ID 0x00-0x03 to your four PICs and upload the exact same "setup_8580.hex" file to all four PICs. Forget about "CC" button, this is irrelevant, in V1 this will only enable sending out parameter changes to the MIDI Out (i.e. to let you record them), and this is different to the master PIC sending parameters to slave PICs via MIDI. "TAKE 1" appears as if all PICs have the same SID device ID, so when you enable "CC", you are sending out CCs for device 0x00 and the other PICs are receiving them, but patch changes are not working because the master is sending out patches for devices 0x01, 0x02 and 0x03 and the slave PICs are all 0x00 and ignore them. "TAKE 2" suggests you uploaded "change_id" app after MB-SID app, this will replace MB-SID app so you would need to upload MB-SID app again afterwards. If you're using MIOS Studio, this will also help you validate each PIC has different MIOS device IDs and so will auto-configure themselves to be master or slaves.

Hi everyone, Thanks for the compliments! TK called this eye-candy outside and inside, a great way of putting it, as it's pretty obvious that I spent a lot of time desiging the inside. When I first read about MB-SID V2 and the possibility of having four Core modules and eight SID modules, I reversed my preference for PCB modules and starting designing a single PCB for the four PICs and eight SIDs, and realised that by doing so, I could optimize it so each pair of SIDs only required two 74HC595 shift registers. Then after choosing the case and discovering I could squeeze in five 74HC165 and three 74HC595, with a neat "hinge-like" cable to the control surface, I then optimized the control surface by using a combined matrix for both LEDs and switches (the rotary encoders aren't in the matrix and use DIN pins). It's hard to say how long this took, as at the same time I was desigining the front panel layout and planning how it would all fit together. I started planning and designing it last May, and ordered the PCBs in October, spending probably 10 hours a week. So PCB design probably took 200 hours over six months, as everything was manually routed and I changed my mind a few times along the way, and a large chunk of that time was routing the control surface PCB. I really enjoy PCB layout, and there's a huge buzz when you get some PCBs in your hands that you designed yourself. Actual construction didn't take that long, but it dragged on for weeks because testing MB-SID V2 alpha was very distracting ;) I actually went with an overall design that would be cheapest to put together (single PCB instead of modules, small control surface area and PCB)... the big costs were AU$170 for PCBs (one-off prototype manufacture, and that's the cheapest for this size) and AU$200 for panels (Front Panel Express). I went to SmashTV's site to work out a comparitive cost: 4 Core modules, 8 SID modules, 1 DIN modules, 1 DOUT modules = PCBs only: AU$102 (US$84) Kits: AU$300 (US$244.80) ... and that's not including SIDs or control surface components! The panels by Front Panel Express were expensive, but in retrospect were well worth it. I don't have the tools to make an aluminium front panel, especially not one that would align with the PCB perfectly. Same deal with the PCBs. I paid a lot because it's a one-off PCB production, but compared to AU$102 for module PCBs, AU$170 for the base PCB and custom control surface PCB is a bargain. (In no way am I suggesting SmashTV's prices are high, it's just that you need a lot of modules to make the same thing as what I'm making). Also, prices in Australia for standard components can be a little more than Europe and USA, and some of the exotic ones need to be bought from distributors or imported. Many people have asked me whether they could get one of these PCBs. A batch run of the base PCBs is in the planning stage, they might cost US$30 each. A batch run of the control surface PCB isn't planned, but two people could split a prototype PCB order and maybe pay US$65 each. People interested in getting either PCB should contact me by PM.

I just got two LCDs with edge-lit backlight that according to the datasheet use 60mA instead of the typical 280mA of LCDs with a LED array backlight. As I don't really want to burn out the white LEDs with too much current, I'm trying to work out if I could accidentally do this with the Core backlight control circuit, which I believe does supply up to 280mA. I know it will probably work OK, as many people have used white-on-blue LCDs before and probably didn't do anything special, but if there's the chance I could be oversupplying the white LEDs and potentially burning them out instantly or reducing their lifespan, I really want to know NOW! So any explaination of the backlight control circuit, or sharing experiences with edge-lit backlights would be most helpful.

There are no stupid questions, just stupid people ;D (disclaimer for the sarcasticly impaired: I'm joking, I'm not calling you stupid!) ... although not a stupid question, it's a bit confusing! Pads are where you solder component pins to the PCB. For through-hole components, you need a hole through the pad, and the pad is then a ring/donut shape. Keep in mind also for some parts like rotary encoders, they have "snap-in" flanges on the sides, so you can put large holes to fit them in, and then bend them on the other side and/or solder them for stability. Good catch... I like someone who points out my mistakes! I started writing my reply about the main board then later realised you're asking about a control surface board. You're right, on the control surface board I use 20mil traces for the Vss, which is only connected to the encoders, as everything else is in a matrix and is sinked by DOUT pins. I probably could have used 10mil there... it is all very low current so 10mils would have been fine. Basically you now know things will work at 10mil without a problem, but unless you've got some really tight layout that requires 10mil, try using thicker traces.

So does this mean you can only get an LCD as replacement? Let us know if you have trouble replacing the PLED, as I know where to get a Winstar 2x20 (that's what Crystalfontz sells, relabelled!), and OSD (One Stop Displays) also make them and I know a supplier for them. Also check on eBay there are heaps of them there.

These knobs are available from ALBS: http://www.albs.de/ part #863062, "Drehknopf DK16-190V3 A.6/4,5 AT=14,5 schwarz soft-transparent rot TR-3925" http://www.albs.de/ecom/images/863062.pdf

... and if you don't cover it, a camera lens cleaning cloth cleans off the messy fingerprints ;D

Seriously, it looks like your MIDI driver for Java is a trial version. I don't know how or why you have installed a trial version...

Oh, the irony... http://www.youtube.com/watch?v=eU9EflLJuf8

I would check a schematic first... the advantage of the C64 PSU is the 9v AC and 5v regulated DC are separate, so you can add 9v DC to 5v DC and get 14v DC, good for a 12v regulator. But if this PSU outputs 9v DC and 5v DC with a common ground, then you can't do the same thing.

When I cracked open a C64 once, it was a beige one but it had a 6581 in it, inside was a huge piece of thin metal sheet with bends in it, attached to the top half of the case, so it touched some of the ICs (like the SID). You can try some of the fancier RAM headsinks, they have a very low height and perfect dimensions for a SID... http://www.performance-pcs.com/catalog/index.php?main_page=product_info&cPath=43&products_id=635 http://www.tweakmonster.com/products/ramcoolerpage.htm I've been deciding whether to get some or not, but I think the 40mm fan and grill on the side is enough... plus 6582s don't get as hot as 6581. btw, did you know you can run a 6581 on 9v? I didn't test the filter, but it does make sound!

I use a ground plane on the bottom layer, so I don't have many tracks of ground, the few I do have are for the SIDs, which I'll explain later. I've used 10mil for all digital signal tracks and short little "branches" off the digital +5v "rails" (eg. to a pull-up resistor, or to hold a chip pin high). The +5v "rails" are clearly visible in the PCB layouts, as they are 30mil, from the PSU section in the top-right corner, it travels down the right side, then splits into two rails, one going under all the PICs, the other going along the shift registers at the bottom edge. All the "audio" tracks for the SID, including tracks to connect the SID's ground to the "audio" ground plane, and the +5v supply to a separate +5v supply rail, are 30mil. I've used 10mil clearance throughout, although I manually give the 30mil tracks a bit more clearance than that, not that it matters much. All vias are 50mil with 28mil hole diameter. Essentially that's all really fat by modern standards, as you would notice just looking at a modern PCB like an LCD module or mobile phone... for digital stuff like this, you could go as small as 7mil, especially for just a control surface board where your currents to LEDs and switches are so small anyway (a few mA at most), but I chose 10mil for convenience (fatter than any PCB manufacturer's minimums) and on the chance I ever needed to fix a track, I'd have a better chance of fixing it ;D Same deal with vias, they're fat but I wouldn't have a problem getting it made. If you're doing mostly PDIP and through-hole, 10mil on two layers is more than adequate. One piece of advice, don't go too small on the pad sizes, I sucked one up while desoldering, so if possible, make it a little bigger. 60mil round pad with a 35mil hole is fine to solder once, but desoldering can be a bit of a problem if you have to... so go up to 80mil round pad, especially if you're planning to solder wires to it that you think you might desolder once or twice.

You might get lucky and get the 1234432112344321 sequence ;) This is already there, you just turn off sorted note stack. IMHO the coolest one is random on all six oscs (3 left, 3 right)... awesome! sorry, now I'm teasing too ;D

Square holes are hard... I think the DIY method is to drill one round hole the same size and just file out the corners, or if it's bigger, multiple round holes, hacksaw, filing... lots of work. You can use JB Weld and threaded spacers on the bottom, then screws through the PCBs into the spacers.

Now that it's finished, I can turn my attention to the PCB layout, make some small changes (size and component positions will stay the same), and depending on the level of interest, SmashTV might get a batch made and sell them, or if that doesn't happen, I'll just release the Gerber/NC Drill files and anyone else can get a one-off made. I find it hard to calculate the total cost, as I'm always buying more bits than I need... As a rough guide: Case: AU$45 20x4 PLED display: AU$45 LEDs, switches, encoders: AU$70 Knobs: AU$20 PCBs: AU$170 Panels: AU$200 Other components (chips, sockets, screws, spacers, etc.): AU$100 (I guess) 8x 6582A SIDs: Priceless ;) So that's AU$650 without SIDs, but I'm probably forgetting a lot of little bits that were bought, a few salvaged C64s, a blue LED 40mm fan (from a Northbridge cooler)... it's probably closer to AU$700 with another AU$100 for the SIDs. AU$800 (US$662, 486 EUR) is a lot, but it's cheaper than an unavailable SidStation, with eight times the SIDs and about a million times the synth capability. I don't know how much an x0xb0x costsA lot of the cost is in the prototype PCBs and panels - buying a batch run PCB and using the aluminium front panels that came with the case would be a lot cheaper. Plus when it comes to MIDIbox, I'm spending the money to have fun while building it, and to build something exactly the way I want it, so in that respect, AU$800 over the past year isn't a lot at all.

Final construction shots (for those into gear porn) :o Link to my Flickr page I finally wired up the last little bits, the four dual-gang pots at the back (for audio feedback), the passive mixer to stereo phono jack, increased the DOUT resistors to 3K, added a pot to turn down (off!) the illuminated knobs, screwed the PCB to the case and it is now all finished! I've eventually decided to turn off the illuminated knobs. One knob by itself does look cool, 15 of them mixed in with the LEDs of the control surface is just too busy, even when I turn down the brightness. Oh well. Maybe one day I'll get those SMD white LEDs and give it a go, for now I'm just going to leave it off. OK, time for some sleep, then I might take some shots for the MIDIbox of the Week ;D

US$4.50 including 10pcs TL074 opamps.

I just thought I'd share this with the MB-SID fans... I bought some 22nF capacitors for my 6582 SIDs (equally good for 8580), they're sold as 2% tolerance but the code "F" at the end of the part number is 1%. They are mylar, not polystyrene, so there's no hassles with soldering them (my capacitors are socketed anyway). The great thing was it was so cheap that I bought 100 and sorted them by value and used 16 of the closest value (so even better than 1% tolerance, mine are all within 0.1nF, so 0.4% tolerance!). 22nF is the recommended capacitor value for 8580 and 6582 according to the datasheet, this is different from TK's use of 6.8nF, but after a lot of discussion, 22nF is the best for frequency range. These caps come highly recommended by me and TK hasn't complained yet about his, so they must be good! Here's the link to them on eBay... for just US $4.50 ;D Mylar Radial 0.022uF 100V 2% Polyester Capacitor 100pcs I'm hoping someone else will copy my example, buy a pack of 100 pcs and share them around like I have ;D

Sorry, I don't get it... what's so great about this 4x4 button matrix? No diodes to prevent ghosting, DIL socket on the wrong side for frontpanel usage, tactile switches with shafts so short you can't poke them through a front panel... sounds like a lot of compromising just to avoid soldering your own. You should be able to make your own with longer shaft switches, diodes and some prototyping board, for less money (OK, maybe an hour or two of soldering) and it's exactly what you want.

Update: I've had a lot of fun with this feedback loop in my MB-SID, and thought I'd share some knowledge. First up, you don't need to follow the wiring like shown in that first link... he's obviously wanting to switch between using an external input, grounding the input, and adding feedback. The easiest way to try out the feedback, but still ground your input most of the time, is to connect a pot with the SID Audio Input (J4:I on SID module) to the middle pin of the pot (the wiper), and the SID Audio Output (J3:O on SID module) to the clockwise pin, and ground (J4:Vs on SID module) to the counter-clockwise pin. This way, if the pot is fully counter-clockwise, the audio in is grounded (just like that jumper you put on J4) and if fully clockwise, it's maximum feedback. So when you're not using the feedback, it's just as good as grounding the audio input with a jumper. I use dual-gang 500K audio taper pots (for stereo SIDs), but you can use a single-gang, or linear taper, or even change from 500K, perhaps 1MOhm might be just as good. Then go and turn on Ext In on the filter ;D You also get different results by turning down the Resonance to 25-ish (don't just leave it at max!) and then turning up the feedback to almost max, then modulate cutoff with an LFO of rate 66 and then tweak depth and cutoff... :o Of course it can also add some distortion if you turn off Ext in on the filter.

Possible, but I wouldn't know how, or if it would work. That's probably a better solution... If you upload MIOS/MBSID with a Midibox-to-COM interface, you can then just reprogram the config bits with your PIC programmer to switch it back to MIDI. Read about the config bits here: http://www.ucapps.de/mios_bootstrap_experts.html and take care with the config bits as some programmers use a different byte ordering, and some don't write anything, leaving it all 0xFF! I reccommend PICPgm. http://www.midibox.org/dokuwiki/doku.php?id=jdm_with_picpgm which might work with your programmer.