2015. június 25., csütörtök

StickVise in work

The USB booster before soldering:


The USB booster after soldering:


I can tell you. I really like this thing. Before I started to use it I was afraid if it sliding on my desk, but realized that it has enough weight to keep it steady while I'm soldering.
In addition it finally became an advantage that it can be lifted from the desk:
On a home made single sided SMD board it is crucial to see the the soldering in light. So I just pick it up from the desk and look through the board. This is the best way to find any accidental short between the IC pins (specially useful for this tiny MSOP-8 package what I used here).

So in the same place this "great, absolutely top of its class" (heap of crap) Aoyue 328 is for sale:




2015. június 23., kedd

StickVise arrived

Finally it is there. Luckily I got them both. I'm planning to try it out on soldering the second version of my USB Booster project during the night or early morning.


CNC motor driver 11. - Learning Chinese, front panel schematics

Reverse Engineering the CNC control board

During the weekend I was trying (still unsuccessfully, but I don't give up) to get the PWM signal generated by the LinuxCNC out from the parallel interface/stepper driver board.
I would like to achieve without soldering (just to have some challenge).
First of all, about the board.
The machine arrived with a JP-3163B board in it, plus and additional stepper driver for A-axis. Actually, I'd like to keep this board and I want to get as many things I can out of it. The board in question is a version 3.9.
What I found out, that the documentation widely available (and already mentioned by me earlier here), is not completely correspond to my board. Even, if I check the pictures of the boards in sale currently on the AliExpress and eBay, are the same as mine, but the documentation is the other (in fact for the v3.6).
If we are talking about the stepper drivers, and the inputs that are the same, but the additional secondary relay, the spindle drive, the jumpers, or the LED's for the A-axis are totally different.
The only information I can get is the Chinese text from the board itself (not to much).

Part of the 3.6:


And the 3.9:


As you can see the upper has 3 jumpers and the lower has 5. (If you didn't realized, the fifth located next to the parallel connector.)
Actually I'm trying to collect as much information about the boards as I can. I found this text somewhere:

现出售的是最新的JP-3163B V3.9版本,增加了延时启动功能和风冷功
能,延时启动是为了更好的保护驱动器不易损坏(风冷为开时,只受Z轴
方向吸合继电器2输出给电磁阀风冷,风冷为关时,做继电器2使用),另
外:本店的手柄只支持以前的V3.7 V3.8 V3.9版本,V3.6版本是不能用
手柄的,请购买手柄的客户买雕刻机手柄时,与店家联系,了解您购买
的板子是否可以配用JP-392Q控制手柄.

Translated (google translate our friends):

Is the sale of the latest JP-3163B V3.9 version, adds delay start function and air-cooled power
Energy, delay start is to better protect the drive easy to damage (air to open, subject only to the Z-axis
Direction of pull solenoid valve relay 2 output to air cooling, air cooling is off, do use relay 2) and the other
Outside: We handle only support the previous version V3.7 V3.8 V3.9, V3.6 version is not used
The handle, the handle when your customers buy buy engraving machine handle, contact with the store, understanding your purchase
Whether the board can be used with JP-392Q control handle.

This is far from perfect, but at least we can see that some changes in the cooling and the delayed start is added somehow to the spindle drive.
About the LEDs, specially the upper three. On the original board I seen somewhere else English text stating the following:

LED1 (Red) - PWR - Power
LED2 (Green) - A-OR - A-axis direction
LED3 (Green) - A-PU - A-axis step

On my board:

LED1 (Red) - 电源  - Power supply
LED2 (Green) - 主轴 - Spindle   (Pin 1 of the parallel port)
LED3 (Green) - 使能 - Enable    (Pin 14 of the parallel port)

I also tried to get some information about the jumpers

JP1 - 5V / 外隔离 - Within 5V / outer barrier (Internal 5V / External supply ???)
JP2 - 使能开 / 关 - So able to open / close
JP3 - 风冷开 / 关 - Air cooling on / off
JP4 - 拟量开 / 关 - Analog On / Off (When I switch this of the previous constant 10V disapear from the spindle control)


JP5 - 手控开 / 关 - Manual on / off

Some of the pins of the parallel port are working differently (or has connection to the Spindle control) than it written on the documentation I found:

1 - Spindle On/Off
14 - ??? (Switch On/Off the LED3, but I didn't found any other impact yet)
16 - Relay 2 (It clearly switch on and of the Relay 2, instead of the stated NC)
17 - ??? (Actually I didn't found any impact, it may NC)

This is the current status. I didn't have more time to work on it. I'll definitely continue this, until I'll able to get out the PWM signal in some way.  

Front Panel Schematics

I finished the first version of the front panel schematic design. It is in the github repo:


I'd like to add some comments to it:
  1. I added lot of external connectors what will not be used but give place for future development
  2. The controls are still fuzzy. I may change some hard buttons to a menu based something controllable via the rotary encoder and it's button. This need some tweaks in the hardware also. This means, the schematic will get some slight modifications before the PCB design.
  3. The software spindle control has no additional circuit, it is just two pins now on a connector. It will be an add-on board with maybe some protection diodes, level shifting circuit, or optocouplers. It will be based on my finding in the first part of this post. On the other hand, I do this, because this keep the things open to connect different kind of CNC boards.
  4. The MCU pins are significantly different from the ones are on the current software implementation (the software will be aligned later). The cause of this, is a misinterpretation of the MCU pins by me. I mixed up the ADxx pins with the AINx pins. The first is external digital parallel bus, what I don't use, and the later is the inputs of the AD converter.




2015. június 12., péntek

Win - Blackfin

As I told, I've my lucky days recently.



I just got a letter from Analog Devices during the night. I won one of the five Blackfin development platform on EETimes Europe's give away:
http://www.electronics-eetimes.com/en/News/full-news.html?cmp_id=7&news_id=222924677#
I've two ideas now, what can I do with this, but none of it public until I jump deeper into it.

Sensirion sample arrived

The Sensirion SHT31 sample I won just arrived.

Two piece in the package. Something like 3x3mm each


Unfortunately they are just bare chips, so I've to find a way to create a breakout for it. I'm scared working with lead less packages (DFN, QFN, etc.), at least because I never tried.

2015. június 11., csütörtök

Expandable breadboard

This story is really short. Yesterday morning when I was driving to work, just pop into my mind, how can I solve my long lasting problem with the breadboards. When I snap in some wide thing it just not leave enough empty holes to connect jumper wires.



Some people had crazy solutions:



What if I cut a breadboard into it's two half, mount it on a pair of sliders and slide to the position where the board fits in keeping the four holes for each pin accessible:


During the day I designed this thing, just in my head. Not drawing or writing a bit. In the afternoon I just run into the store and grabbed the things I didn't had at home. The sliders, the aluminum profile and the wood (I've pinewood at home, but I didn't wanted to run into a lengthy woodworking experience).
In the evening when everybody went to sleep, I started to work on it.
Picked one of the three breadboards, and cut it into two pieces with my proxxon micro table saw.
Cut the necessary FR4 boards, the aluminum profiles and the wood also. Drilled the holes into the necessary places, and screwed everything together. When it was done, glued the breadboards into its place with the original two sided tape attached into its back.
Finished. It took around two hours.
Probably fastest project of my life. :-)




2015. június 10., szerda

Arrived

Something arrived.

What?
My Pebble Time :-)


PCB vise

A few month ago I bought a PCB vise:



I found out that this one is close to the useless crap. It is not enough that is optimized for 0.8mm board thickness and I usually use 1.6mm boards, but the mechanics of the vise is catastrophic. I tried to use it a few times, but I hate it.
I was looking around the Hackaday store lately and find the Stickvise. It looked great, and I was thinking to buy one, but I've always problem with the shipping costs.



Now I decided not to buy. I'm positive, I'm absolutely sure, I'll not buy it, because...
I WON!!!
To be precise, I won two of it. Both of my projects (CNC Motor Control, USB Booster) sent to the Hackaday.io-s 2015 Hackaday Prize competition was awarded with a Stickvise this week.
I love to win things, especially things useful for me. Thank you guys.

2015. június 9., kedd

LightUp - Founding Canceled

I'm confused.
When the new campaign of the Faraday kit in the Kickstarter started, it was promising to get it founded. After a few days (let say after a week) it looked like it will not reach the goal.
On the last week, some big contribution went in, and looked like it will be close, but they can make it.



Today came a note. Campaign canceled, with this note:

"Hello Kickstarter friends,

It’s been incredible to see your outpouring of support to help bring this project to life. As you might imagine, a lot has been going on behind the scenes as well. We expected that it’d be a wild ride, but even knowing that we couldn't have predicted what the last few weeks would bring.
A tremendous opportunity literally just popped onto our radar (like…yesterday). We can't divulge too much yet, but in short we're in our strongest position ever to fund and launch our next generation of kits in a big way later this year. It was a tough choice, but to be able to pursue this newly opened path we're ending this campaign and returning your pledges.
We know you all are our earliest and strongest supporters, given that you've pledged your hard-earned cash for what we're making. We want to assure you that we’re as committed as ever to producing and delivering our new kit to your doorstep. This new path keeps us on a similar timetable, without tying up your funds unnecessarily to boot!
As a gesture of thanks for your early support, here's what we're going to do:

  • Provide a discount coupon for our Edison and Tesla Kit (available now)
  • We know many of you early adopters are excited by features of our new kit, so when we’re closer to completion we'll provide an opportunity for you to grab it at the Kickstarter price.
We'll be messaging our backers directly so you can take advantage of either (or both) of these offers. Thanks again, and stay tuned for more!

Tarun & Josh"


I don't know what to think.

2015. június 8., hétfő

TI Precision Labs Replica

Texas Instruments recently published a great video and lab series, for teaching some hands on and in depth knowledge on operational amplifiers here:
http://www.ti.com/lsds/ti/amplifiers-linear/precision-amplifier-precision-labs.page
I think, this is really a great idea. Dear TI, Thank you for providing this for the community. I really like it.
There is a problem with it on the other hand. The price for the NI's virtual lab is not for a hobbyist - Ok, we can use our own test gear for measuring.
And the price of the evaluation module for it is insane $199 for a board with few passives and few pluggable Op Amps???



Come on! This is the same company who spread the world with the $5 LaunchPads - Encouraging me to jump back to electronics after 20 years?
I just run around my sources with the BOM, not even trying to find the cheapest solution, even counting the shipment cost, calculating only one board, and the cost would be around 50 bucks. Even less if I put some research effort into it.
So, lets the journey begin. I'll replicate this kit...

2015. június 7., vasárnap

USB Booster 0. - :-)

A few month ago I started a project called USB Booster. It doesn't hit this blog as I had not enough time to write about it here. It is just started on the Hackaday.io.
The problem:
I've a huge amount of various development boards. These boards almost exclusively powered from USB. It is just happened that I've no powered USB hub (I even tried to buy one, but the one I was coosing, wont fit into my needs).
Some of the boards really require the 5V. If you measure the voltage on the USB - hubs, cables included, with a load of a high power dev board (like STM32F429-DISCOVERY), it could fall to 4V or even lower. It happend to not enough to this board. The application USB wasn't working.



The solution:
It pop into my mind, what if I just put a switch mode boost converter into the USB power line, and allow the data lines to connect to the board?
It is a simple dongle put between two USB cables, no external supply needed and done.
I was thinking to build it with the common MC34063, because it is easy and cheap. Later I realized, that the result will not be cheap because the big external components (low switching frequency), and in addition it be big and inefficient. So I dropped it.
The project kept in this state for months.
A few weeks ago I was searching for a cheap boost converter for an other project. Suddenly I found Microchip MCP1642. It turned out, that it is not suitable to that project, but nicely fits into this.
So the story begin here...

2015. június 1., hétfő