Difference between revisions of "Building Glasgow"

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  |Picture=Glasgow-render.jpg
 
  |Picture=Glasgow-render.jpg
 
  |Omschrijving=debugging PCB assembly so we can build a PCB to debug our PCBs
 
  |Omschrijving=debugging PCB assembly so we can build a PCB to debug our PCBs
  |Status=Initializing
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  |Status=In progress
 
  |Contact=noopwafel
 
  |Contact=noopwafel
 
  |Contact1=Shiz
 
  |Contact1=Shiz
 
}}
 
}}
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 +
We're going to try assembling some Glasgow [https://github.com/GlasgowEmbedded/glasgow] PCBs. The FPGA is BGA, and there are >100 jellybean parts to place, so we are using the [[Reflow Oven]]. Failure is fun!
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=Want one?=
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We have enough parts for 5 boards, and most of the parts for another 5; costs should be no more than 100eur (you get our assembly time for free).
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{| class="wikitable sortable"
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|-
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! Who? !! How many? !! Built?
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|-
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| noopwafel || 2 || Partially (1)
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|-
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| Shiz || 1 || nope
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|-
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| Eightdot || 1 || nope
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|}
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Obviously we're hand-building these, and we'll test them as well as we can, but: no warranty (other than you coming back and we can debug them together and replace any dead parts). :) The Glasgow boards are designed to be pretty resilient (e.g. there's no problem if you short stuff to ground). At some point there will also be a [https://www.crowdsupply.com/1bitsquared/glasgow official crowdsupply campaign] by esden, with mass-produced boards.
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=Status=
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As of 18th Feb 2020, the first board works, but pin A7 is flaky. Replaced the level shifter on Feb 20: now everything seems to work! Look at the pretty lights:
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 +
[[File:Glasgow_working.jpg|500px]]
  
 
=Wha?=
 
=Wha?=
We're going to try assembling some Glasgow [https://github.com/GlasgowEmbedded/glasgow] PCBs. The FPGA is BGA, and there are way more than >100 jellybean parts to place, so this will probably involve the [[Reflow Oven]]. Failure is fun!
 
  
 
Glasgow is described as an `open source multitool for digital electronics'; it's basically an FPGA with configurable level shifting for 16 ESD-protected I/O pins, so you can connect it to a whole bunch of random interfaces:
 
Glasgow is described as an `open source multitool for digital electronics'; it's basically an FPGA with configurable level shifting for 16 ESD-protected I/O pins, so you can connect it to a whole bunch of random interfaces:
  
[[File:Glasgow-block-diagram-1.png|800px]]
+
[[File:Glasgow-block-diagram-1.png|500px]]
 +
 
 +
=Log=
  
=Status=
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noopwafel tried making one in the reflow oven (14th Feb 2020). Next time need to check reflow temp profile, placement in oven, placement of components, how to apply solder paste, need better tweezers, and there are other lessons along those lines. Having said that, it looks OK:
 +
 
 +
[[File:Glasgow-reflow-attempt1.jpg|300px]]
  
 
We ordered 50 revC1 PCBs and a stencil from JLCPCB.
 
We ordered 50 revC1 PCBs and a stencil from JLCPCB.
* They are currently being manufactured. They asked for confirmation that the solder mask layer was meant to be missing the DNP parts, replied.
+
* They asked for confirmation that the solder mask layer was meant to be missing the DNP parts, replied.
  
noopwafel plans to buy about 10 board's worth of components; the total BOM cost is about 70eur in these quantities.
+
noopwafel bought about 10 board's worth of components.
 
* We managed to import a BOM into Mouser, and to break Digikey's BOM manager.
 
* We managed to import a BOM into Mouser, and to break Digikey's BOM manager.
* Mouser has almost all the components, except we need to substitute some jellybean parts and some LEDs.
+
* Future thoughts: the HX4K is 1eur cheaper. Also, jellybean parts could be cheaper.
* The FPGA is only available in useful (small) quantities from Digikey.
+
* noopwafel has a BOM spreadsheet for managing this now; order split between mouser, digikey and TME.
 +
* In theory, we now have all of the parts we need! (Later note: turns out we missed 18pF 0402 caps, but there were some in the space's inventory.)

Latest revision as of 17:32, 1 March 2020

Project Building Glasgow
Glasgow-render.jpg
debugging PCB assembly so we can build a PCB to debug our PCBs
Status In progress
Contact noopwafel, Shiz
Last Update 2020-03-01

We're going to try assembling some Glasgow [1] PCBs. The FPGA is BGA, and there are >100 jellybean parts to place, so we are using the Reflow Oven. Failure is fun!

Want one?

We have enough parts for 5 boards, and most of the parts for another 5; costs should be no more than 100eur (you get our assembly time for free).

Who? How many? Built?
noopwafel 2 Partially (1)
Shiz 1 nope
Eightdot 1 nope

Obviously we're hand-building these, and we'll test them as well as we can, but: no warranty (other than you coming back and we can debug them together and replace any dead parts). :) The Glasgow boards are designed to be pretty resilient (e.g. there's no problem if you short stuff to ground). At some point there will also be a official crowdsupply campaign by esden, with mass-produced boards.

Status

As of 18th Feb 2020, the first board works, but pin A7 is flaky. Replaced the level shifter on Feb 20: now everything seems to work! Look at the pretty lights:

Glasgow working.jpg

Wha?

Glasgow is described as an `open source multitool for digital electronics'; it's basically an FPGA with configurable level shifting for 16 ESD-protected I/O pins, so you can connect it to a whole bunch of random interfaces:

Glasgow-block-diagram-1.png

Log

noopwafel tried making one in the reflow oven (14th Feb 2020). Next time need to check reflow temp profile, placement in oven, placement of components, how to apply solder paste, need better tweezers, and there are other lessons along those lines. Having said that, it looks OK:

Glasgow-reflow-attempt1.jpg

We ordered 50 revC1 PCBs and a stencil from JLCPCB.

  • They asked for confirmation that the solder mask layer was meant to be missing the DNP parts, replied.

noopwafel bought about 10 board's worth of components.

  • We managed to import a BOM into Mouser, and to break Digikey's BOM manager.
  • Future thoughts: the HX4K is 1eur cheaper. Also, jellybean parts could be cheaper.
  • noopwafel has a BOM spreadsheet for managing this now; order split between mouser, digikey and TME.
  • In theory, we now have all of the parts we need! (Later note: turns out we missed 18pF 0402 caps, but there were some in the space's inventory.)