latigid on

Hello, welcome to the forum! That shouldn't be a problem, just leave J17 open/not jumpered.

You do know that the BLM you're going to get has 4 sliders and 4 available AINs right ? :smile: It's pretty good really, as the 8 bit Core gets a good workout this way. At the moment they can't be selected in the "External Control" section, but I bet TK will add this soon enough. Another option would be to go down the MBCV path and convert some CVs to CCs, then use a second MIDI in for control. EDIT, sorry, this was mentioned just above...

Dear all, many thanks for the PM responses so far. I am currently waiting on info from grizz, ganchan, blingy, and sonicwarrior. The PCBs are basically finalised, I will order the batch and build another, then commit to buying cases. If I can get payments reasonably quickly you might get your boards in 4-6 weeks or so.

I've spent a few days scratching my head with the BLM. Basically when applying power the Core boots up fine but the LEDs are lit up, sometimes all, sometimes in random patterns. I have a Meanwell 2.5A SPSU supplying 5V to both the Core and the BLM+miniCore. What I imagine happens is the SRs have undefined states on startup which leads to a kind of latch-up condition. If I reset the power once the miniCore and 5V are stable, the communication initialises as expected. Having a hard reset button is a bit too brute force, so I've arrived at a solution which works every time. I essentially cut the 5V line and implemented a low pass filter with a 0.68R resistor (cap is 470 uF). This does draw a bit of current, but suppresses the initial spike and there is little to no loss in brightness. The LPF is after the miniCore's power, which always initialises first. It's possibly peculiar/particular to my PSU, I'd love to scope the start up but I don't have a DSS... Linear supplies with good regulation will probably have no trouble. I thought CMOS chips normally had a power-on reset, but it seems like the combination set up in the BLM (current surge? long chains?) can produce some strange results. Perhaps another method would be to control the /OE pins of each shift register, but I can't think of a neat way of doing that without tying up 24 MCU pins or having horrible fly wires everywhere. So, more of an FYI as I have a solution already, but of course any insight or experiences are welcome.

Cases are $270 due to the modifications mentioned. Postage a little cheaper. 18 button pads are $79 from Mouser. I will post when next travelling to the EU for cheaper shipping, unless you prefer otherwise :)

Okay, I've sent out PMs to request addresses etc. I'm looking to get the PCB finalised, then I will start to request payments. Best, Andy

Sweet! That's about the same size as the BLM, would make a good couple on the MIDIbox battledeck! Well done,

Another point: Mouser have gotten back to me about the button pads. While they are listed as "non-stocked", apparently the delivery time is 1-2 weeks. The pricing is fair, but there will only be about $10 difference in a larger bulk order, so it's easier for everyone to just get theirs directly. This is a great way to get almost everything in one order, especially for Europeans who will even get free shipping.

Okay, case revs are final then. :) I've made several improvements which will bump the price up slightly, these include 6 extra studs and 4 threaded holes to secure the front panel, the latter M2 grub screws are optional. Everything is nicely symmetrical and even functions as a visual guide. Also my idea of mounting the rubber feet through the bottom nuts didn't work because the actual screw threads are too short to get past 3.2 mm aluminium and into the integral nut. So there are 4 more there and these are the reasons for extra cost. I think you'll be very happy with the cases though, they're sturdy and stylish.

Interesting, it looks like Mouser will soon stock the button pads. If so, that's a great way to get almost everything in one order. I'm a bit busy but I'll try to get PMs out in the next few days to confirm addresses, payment details etc. Mouser part: 485-1611 Currently out of stock but I've requested a delivery quote.

Another good one! Very picturesque at the end there.

Thanks! Maybe it's weird lighting, but this BLM has three colours: blue, green and cyan (and off). The way I've wired the LEDs would correspond to TK's green, red and yellow. You could also choose to swap the green with red, then you get pink as the third colour.

Looking good! Lamouette asked if the illumination is okay in sunlight. I shone a 10 W fluoro lamp on and you can still make out the colours although it's much better when it's a bit darker. In any case I'm happy with the brightness.

Bonus: you could use the holes as sockets for CV inputs to control the SEQ. :smile: Would need to implement a diode protection circuit, but there are two a "muck" areas onboard.

Here the hole centres are 25 mm apart, same 10 mm diameter indicated in green.

This shows the internals, I don't think it's possible to fit both in a vertical line. Horizontal I can do, the green outlines are 10 mm. But of course it's nicer to have all the cables out of the way on one side.

Is this okay for you? You would have at least 14 mm diameter clearance. Feel free to suggest another idea if you like, the red zones are essentially where the case bends. Remember that this is aluminium, not steel, so it is no trouble to drill if you wanted to wait until you have all the parts at hand. It's a bit difficult to place the holes without seeing the parts you're using. Everything is more or less working, but I should test a new PCB to be sure. If you like there's a waitlist for the next batch in the Bulk Order section.

Looks like it shouldn't be a problem to optionally add holes for power switches (I will confirm orders and collect addresses etc.). To check: the switch and barrel connector holes are 13x12 mm and 11.1x9.1 mm as per TK's Schaeffer file? I notice a lot of SEQs with a lot of different power entry requirements, I'd have to settle on one design.

Waitlist PCB BLM PCB miniCore Case Shift button M2 hardware 4xLED latigid on 1 1 1 1 1 1 Total 1 1 1 1 1 1

Name PCB BLM PCB miniCore Case Shift button M2 hardware 4xLED latigid on 1 1 1 1 1 1 Rowan 1 1 1 1 1 1 Phatline 2 2 1 2? 1 1 TK 1 1 1 1 1 1 Altitude 1 1 1 1 1 1 rwo 1 1 1 1 1 1 jojjelito 1 1 1 1 1 1 tashikoma 1 1 - 1 - 1 workspace 1 1 1 1 1 1 flyweight 1 1 1 1 1 1 Grizz 1 1 1 1 1 1 blingy 1 1 - 1 - 1 ganchan 1 1 1 1 ? 1 Macotronic 1 1 - - - - sbm 1 1 1 ? ? 1 Jack 1 1 1 ? ? 1 tabularasa 1 1 1 ? ? 1 sonicwarrior 1 1 1 ? ? 1 jbdiver 1 1 1 ? ? 1 Total 20 20 16 14(+5?) 10(+6?) 18 Okay, I will have to CLOSE this order now, mostly because of the shipping effort from my side. All others who are interested can go on a waiting list for the next batch or jump in if people above are too slow to pay etc.

With a scope or multimeter you can see if the power rails stay stable. You can also measure current levels and compare the difference between your LPC17 and STM32 cores. Note that the LPC17 has 780X regulators which should be good for 0.5A without heatsinks. How is the +5V regulated on the STM32F4 board?

Are you using USB power? Can you monitor the appropriate supply voltages?

Why not go for the maximum PCB size? A bit more symmetrical this way.