This weekend Ken and I have been engaged in the very first build of the myStorm board, Ken recalls the last 24 hours – over a well earned pint……
Brewing Up a Storm
This week we saw the arrival of the first batch of myStorm pcbs from Toby in Shenzhen. The gerbers were sent on Thursday 21st July and pcbs – plus solder stencil arrived the following Thursday lunchtime – quick work.
Meanwhile Alan and I had been out shopping for the BOM parts – with enough components to build up a small prototype batch of about 5 boards.
We got together on Friday evening at the Surrey and Hants Makerspace and managed to spend a couple of hours painstakingly placing the 80 or so 0402 parts onto the freshly screen-stencilled – solder pasted sample pcb.
In fading light we retired with more than half the SMT components placed, with a view to completing the task in the fresh morning light – when both our eyes and hand co-ordination would benefit from a good night’s sleep.
The placement continued for another 2 hours in the morning and by 11:30 we had a fully placed board.
After some basic checks for IC alignment – we turned on Alan’s home made hotplate – an aluminium block, with a cartridge heater and a cheap temperature controller.
Setting the temperature to about 220C – within 5 minutes the board was starting t show positive signs of solder paste reflow.
The pasting operation had been not 100% successful, – the definition of the solder pads around the pins was far from perfect – but with the application of heat – and the miracles of surface tension – the solder flowed beautifully – leaving perfectly soldered pins and 0402 components.
A quick bit of remedial work to fix any “tombstoned” components, I was onto the last leg of this demanding race – and soldering the PMOD and Arduino connectors into the remaining through-hole locations on the board.
Initial Tests
Check, check and check again – then correct the things you missed.
First we checked for supply to ground shorts – and the 3V3 was connected to 0V – because a single 0402 100nF decoupling capacitor had moved sideways across its pads and was shorting across them. Easily fixed – but not so easy to spot in the first place. A few solder bridges between pins on the 64 pin LQFP ARM package – again easily fixed with the soldering iron and a dab of water-solvent based SMT flux.
Then it was time to apply the 5V power and test the power rails. All appeared well with 1.2V for the Vcore and 3V3 as the digital supply to the ARM and the FPGA.
On first power-up some of the LEDs glowed dimly – and the power light glowed yellow.
Next we had to find a way of getting some life into the ARM chip – an STM32F103RC – the same as used on the Nucleo dev board. I opted to get “Blinky” running – using mBed to program the board.
Downloaded the ST Link Utility – which included the latest drivers and the programming application. Once this was down loaded it was relatively easy to use the blink example, change the port Pin to PA_15 and flash the LED!
A first success!
Tomorrow – there are 2 more prototype pcbs to populate and bake. Once you have done the first one – fixed the snags – the rest is easy.
If you are interested in getting involved with myStorm you can register on the myStorm forum for announcements about workshops, events and product shipping or early access to products etc..
Also there is a good background as to the why of soft hardware in the Quickening
Good job designing this board, it looks pretty nice ! Maybe I missed the information, but are you planning to going further than releasing the design ? Like, lauching a kickstarter to produce and sell it ?
Hi Tropicao
Thank you for your nice comments, Good questions, I will try to answer best I can :
MyStorm is designed as opensource from the start, we will be releasing the Eagle CAD files and source code shortly just as soon as I have cleaned up our repo, please be aware I am still in the middle of writing the STM32 code for programming the FPGA and juggling to get everything done, please bare with us. We have no plans for kickstarter for myStorm, however, we will be making the boards available through several partners whom we are currently negotiating with. As a timeline : :
Sorry for not being more specific on dates by this thing is moving fast…
regards
Al
Thanks for the reply, I was not waiting for very specific facts and dates(I understand that it is an early stage), I am glad to hear that you are searching for partners to distribute the board🙂 I will keep an eye on the project status !
It’s probably way more hassle than you should be expected to take on, but if there was some kind of mailing list that we anxious and eager potential customers could sign up to in order to give you all our money at the earliest possible opportunity… I’m there! :))
Hi Charlie
The mailing list is a good idea, I will work out how to get that organised, Watch this space, thank you..
Thank _you_!
BTW there is now a forum/mailing list Charlie https://forum.mystorm.uk/
Get in touch if you’d like me to add this to my review pile on EDN (michael.dunn at aspencore.com)
Will do michael, thanks
Great project.
Once you get your boards up and running, if you are looking to do a larger run, please check out groupgets.com, we just did a run for the google PRUDAQ https://research.googleblog.com/2016/07/announcing-open-source-adc-board-for.html
Its a good way to get to order a larger run. Or if you just want to off load the whole PCB assembly process we can handle that as well, we have several PCB assembly partners in USA and china.
Thanks Sashi we will take a look groupgets.com
Congrats, this is great news ! I have a doubt about programming this pieces of artwork : well obviously the STM stuff is gonna get done through C, but what about the gate arrays ? Do you really have to go through Verilog or do you know of workaround for using C as well ? Regards, Elliot Alderson
Hi Elliot
Yes right now it’s Verilog for the FPGA, longer term we are working on some modular linking of Pmods into C and maybe other languages like python on the RPi.