vController v3 build journal

Started by vmarks, September 12, 2017, 02:40:47 PM

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vmarks

Hi!

I hope this makes for an interesting post and thread: I'm going to document my building a vController v3 from sixeight's plans as posted on github.
https://www.vguitarforums.com/smf/index.php?topic=15154.msg108132#msg108132

https://github.com/sixeight7/VController_v3
https://github.com/sixeight7/VController_v3/blob/master/VController%20guide%20-%20production%20model.pdf


I'm not an engineer, although I first soldered when I was ten. I am not a software developer, either, although I used to use Linux primarily almost 20 years ago. I'm not afraid of following instructions, having been told RTFM when the manual was incomplete all that time ago.

I recently started playing guitar with some friends on weekends, and my Line6 pod2.0 and Variax 500 both are showing signs of intermittent failure. I don't want to carry a pedal board around, or a large amp, or anything else nuts. I like to plug into the PA and have something manageable.

I saw the videos sixeight had posted, and was very interested in them. When he showed Zoom G3 and MS-70CDR compatibility, this made it easy. I picked up a G3 on craigslist for $70 USD and patched it to a MIDI foot controller from 1992 (Peavey PFC10) using a Raspberry Pi and an ancient M-Audio Midisport 2x2 USB adapter. This cinched it for me - being able to foot switch patches is huge. The promise of having the names of patches displayed and being able to switch out all six effects individually makes it a winner.

I started messaging sixeight, and getting the files sorted out. On September 6th, I started figuring out the BOM (bill of materials - the parts list) on September 7th, I cross-shopped PCB production, and on the 8th, I placed an order for 5x Main boards, 5x display boards, and 5x of the midi boards (because they literally added a total of $5 to my order cost. Even if I only build one, it will be faster and better than using the USB Midisport 2x2 I have in place now - that requires firmware to initialize it. The Pi loads the firmware but I have udev rules where they're supposed to connect MIDI in and out ports on USB detection, which doesn't work because the firmware hasn't loaded when it detects it. Such is life.)

I decided to use PCBway.com as the maker of my PCB boards. This was because they came in cheaper than anyone else before discounts. https://pcbshopper.com was useful for making comparisons. I also signed up at 4pcb.com for a 50% discount on my first two orders. PCBWay offers a 5 dollar off and a 50% discount coupon in exchange for publishing a youtube video about the boards. I also looked at using Oshpark.com, which gives purple soldermask with gold. I ended up specifying black solder mask with HASL, which will be fine. Purple from other suppliers besides Oshpark was an upcharge.

Believe me, I thought about making the boards purple and gold. I did.

The ordering process was easy. Painless, even. It was very easy to get ahold of people at PCBWay and ask for assistance, throughout the ordering process. They have some free universal strip boards, which I added to the order after the order had been placed. It upped by a couple dollars on shipping, but even that wasn't painful.

In order to get quotes on boards, you have to input dimensions. I used gerber-viewer.com to get rough dimensions for the boards. The display board is 68mm x 144mm. The main board is 213mm x 60mm. The external MIDI board for Raspberry Pi is 57 x 89 mm.

Depending on where you get them made, you have to account for MOQ - minimum order quantity. This means, I now have 5x of each board coming. I have enough to make 1 vController with four extra Main boards and 1 extra display board. If I need to build more, I can order just the display board for a little while.

The next big steps are figuring out if the displays I'm going to use come from Adafruit or BigDisplay. If they come from BigDisplay, I can use an enclosure that sixeight has already had made. If I go with the Adafruit ones, I'm going to need to get my own enclosure made. The displays are similar in size, but one has a slightly larger bezel size that makes a difference. The other choice is, do I use monochrome displays for higher visibility, RGB displays for color state of the switch (which means eliminating the LEDs).

I had wanted to use 33mm arcade buttons with multicolor LEDs in the button, but I had failed to account for the space constraints in the vController. The vController is surprisingly compact, with no extra room for switches with greater depth or diameter. I've begun to decide to use soft momentary foot switches, I think. (This is still a little up in the air). The largest diameter switch that can be used seems to be 18mm.

I'm going to convert the BOM from a table in sixeight's PDF to an xlsx/CSV that I can load into Octopart.com in order to figure out best pricing at mouser/digikey/jameco/adafruit. Some of the suppliers he used are based in Europe, and shipping would be slower and exorbitant. If I'm going to go with slow shipping, it may as well come from China, but I'd like to be able to have the BOM in a format that it could be fed to one of the common US parts sellers and more-or-less be purchased with ease.

Once I have the PCBs, displays determined, enclosure sorted out, BOM cleaned up and ordered, then I'll be able to begin assembly.

It's September 12th. My boards completed routing, testing, and packaging for delivery last night. I chose slow shipping from China to save a few dollars, so it's going to be about 10-15 days until they arrive. I'll be using that time to try and sort out the BOM ordering.

I'll still need to sort the enclosure and perspex. I have yet to try and get it quoted, or I may impose on sixeight to sell a set to me. I'm still undecided.

I'm attaching a picture of my PCB progress - it's all I have to show so far.

vmarks

I haven't made a lot of progress since I last posted. The PCB are in transit.

The displays seemed like a reasonable place to work next. The two approved sources are buydisplay or adafruit. They are slightly different in dimension, so they have an impact on enclosure sourcing.

They're somewhat costly. Buydisplay gets all 13 displays done, and they're ones sixeight has used before, for $82 USD. Now tack on an additional $33 in DHL fees. Adafruit has the 16x2 displays, but they're 10 USD each, which adds up quite quickly.

More searching is needed.

Elantric

#2
https://github.com/sixeight7/VController_v3/blob/master/VController%20guide%20-%20production%20model.pdf

Quote from: vmarks on September 15, 2017, 10:53:12 AM
I haven't made a lot of progress since I last posted. The PCB are in transit.

The displays seemed like a reasonable place to work next. The two approved sources are buydisplay or adafruit. They are slightly different in dimension, so they have an impact on enclosure sourcing.

They're somewhat costly. Buydisplay gets all 13 displays done, and they're ones sixeight has used before, for $82 USD. Now tack on an additional $33 in DHL fees. Adafruit has the 16x2 displays, but they're 10 USD each, which adds up quite quickly.

More searching is needed.

https://github.com/sixeight7/VController_v3/blob/master/VController%20guide%20-%20production%20model.pdf

http://www.buydisplay.com/download/manual/ERM1602-3_Series_Datasheet.pdf



ERM1602DNS-4-5V
http://www.buydisplay.com/default/3-3v-5v-16x2-1602-character-lcd-display-white-on-black-high-contrast
http://www.buydisplay.com/download/manual/ERM1602-4_Series_Datasheet.pdf


--

ERM1602DNS-1-5V
http://www.buydisplay.com/download/manual/ERM1602-1_Series_Datasheet.pdf




These use SPLC780 LCD Controller - so other 16 x 2 Displays can be employed, just need to verify they use this same SPLC780 LCD Controller IC

http://www.buydisplay.com/download/ic/SPLC780.pdf


like this one - is very close the ERM1602-3-5




   
New: A brand-new, unused, unopened, undamaged item in its original packaging (where packaging is ... Read more
Marke:   Markenlos
Viewport area size:   64.5X13.8/16.0   Herstellernummer:   nicht zutreffend
Controller:   SPLC780C or EQV   Fast Fulfillment:   YES
Operating voltage:   5.0V   Dot Matrix:   16X2
Specifications:   STN   Dimensions:   80.0X36.0X12.5mm


http://www.ebay.com/itm/LCD1602A-Zeichen-Dot-Matrix-LCD-Anzeigemodul-16x2-Black-Background-4-Farben/331699510309

sixeight

#3
QuoteThey're somewhat costly. Buydisplay gets all 13 displays done, and they're ones sixeight has used before, for $82 USD. Now tack on an additional $33 in DHL fees. Adafruit has the 16x2 displays, but they're 10 USD each, which adds up quite quickly

A few considerations:
* the first VController I built with one display has a bad visibility.  It was white characters on blue. I could not read it standing up while the VController v1 was on the floor.
* Display size usually only talks about the PCB size, not the Bezel size. The holes in the top plate are made to the bezel size.
* You can use either China post or DHL to deliver the displays. The first two times I has displays delivered by China post it was fine, but the third batch was troublesome. I had to order twice and pay taxes in the Netherlands as well. So I ended up paying €120 euros for 14 displays (needed one large display extra for the RGB version) I am still trying to get my money back on the batch that was never delivered. In the future I will order in two batches and split the risk. Also I won't have to pay taxes that way. But those are the tax rules in the Netherlands.

vmarks

Thanks for this, Elantric, and thanks for the reminder about bezel size, sixeight.

I can purchase the buydisplay displays from buydisplay via ebay, which overcomes the problem with non-delivery: if it doesn't arrive, ebay enforces the refund rather than having to negotiate it with buydisplay. The biggest risk of a non-delivery in this example is that it stretches out the timeline.

I was trying to avoid using ebay for the BOM in order to make it easy and repeatable to just feed it into mouser (for example) - my big idea was to make it so the whole thing could be a kit with just a few suppliers. That seems to be still possible, but I'm going to balance that with my goal to spend as little as possible and order some of the parts from ebay. Using buydisplay as the seller and ebay as the channel doesn't break it for me too badly, because buydisplay isn't a fly-by-night seller the way others might be.

More things to think about -

on ebay using buydisplay as the seller, the cost of the black on white display is half the cost of the white on black display, and the large display is also have the cost of the white-on-black displays.

Thinking.

vmarks

News!

My PCBs for this project are in New York. Given the state of the United States Postal Service, I may have them as soon as six days from now.

I have not yet ordered other parts from the BOM. Waiting on some cash influx and then I'll place some orders.

vmarks

Welcome to PCBs!



I ordered the Main board and display boards in black soldermask with white silkscreen, and the external MIDI boards (which only cost a dollar each!) in white soldermask with black ink. I'd forgotten I had done this. I was surprised by how nice they came out - the silkscreen is aligned perfectly, and the cuts and routing look spot-on.

I did not permit them to edit the files and add the order number to the boards.

I thought briefly about adding an 'assembled by vmarks' to the boards, but passed. This is sixeight's work, I'm just replicating.

vmarks

Update:

Enclosure ordered from sixeight (thank you!)

Vinyl covering for enclosure delivered.

MIDI connectors arrived.

Teensy3.2 ordered. RPi: I have a few, v2 and v3. Debating whether or not to bother putting the v3 in with its built in wifi and BT. I may just use the v2 and have to open the enclosure for OS updates to the SD card.

Displays ordered! This, the PCB, and the enclosure are the bulk of the costs.

The point is, progress is being made.

sixeight

QuoteI may just use the v2 and have to open the enclosure for OS updates to the SD card.

I stick a network cable in the back and configure the RPi via ssh.

vmarks

#9
Quote from: sixeight on October 27, 2017, 12:17:38 AM
I stick a network cable in the back and configure the RPi via ssh.

My experience with pi is that I can do that for short periods of time - but every six months or so, raspbian changes things and breaks stuff such that I'm better off reloading the card with the latest distribution. Yes, you should be able to update /etc/apt/sources and have it upgrade the distro, but the most recent time I did that, it broke everything.

Also: ethernet only is somewhat annoying. laptops require dongles to attach ethernet, so what I'd really need to do is place the v3 at the router, connect the cable there, and talk to it wirelessly over the lan. mildly annoying due to where I've placed the router for best signal dispersion.

It's turtles all the way down. :)

vmarks

UPDATE:

I have:

boards.
enclosure and rpi accessory mount.
3d printed bits.
displays.
vinyl wrap for enclosure (this is going to be so very cool.)
teensy
rpi
midi connectors

needed:
discrete electronics
connectors
dupont cables
header pins
footswitches
multicolor LEDs and LED holders
other things I'm forgetting.

Moving slowly, but moving.

sixeight

Great. You have most of the expensive stuff. The discrete components cost next to nothing... The footswitches will cost a bit, but the rest is not that much...