#RaspberryPiPico silicon teardown time!

Board as received optical + x-ray images
Inspecting package. X-ray shows bond wires easier after removing thermal slug
Thermal slug removed w/ HCl + H2O2
Decapped to show copper bond wires connecting die to package pins. Initially used only nitric acid which destroyed copper bond wires (last image). Fixed by switching to mixed nitric + sulfuric acid
Zoomable top metal die image: https://t.co/MXqDBvNgqG
@Raspberry_Pi marking it's turf
B0 => chip revision. On every layer? A chip I worked on did this and unfortunately when we fixed a bug on a *different* metal layer we didn't want to remake the masks with the text. Thus "B1" chips were mislabeled as B0!
M8 => eight metal layer chip. Higher metal layers are coarser to carry more power and reduce manufacturing costs. You can also see M7 and M6 marked
Copper bond wires were eaten by nitric acid leading little dimples where they used to be attached to the bond pads
Several unused power pads. Possibly breaks out internal core voltage for debug / test
Time lapse etching chip layers
This area wasn't 100% etched, leading to vibrant blue/purple from SiO2 thin film interference
1) 20x air vs 2) 60x oil objective: 60x has higher resolution but lower depth of field, making the image appear different. Ex: although the lower left splotch is large, it's only visible in the 60x image. I might take SEM images later for better resolution
Transistors arranged into standard cells form the majority of the digital logic. This includes both the CPU and the digital portion of most peripherals
A few different I/O showing logic, ESD protection, etc between the top metal and transistor layer. A number of different I/O IP blocks are used. Would be interesting to match them up to the datasheet for analog functionality like ADC, USB, etc
Memory, probably the boot ROM
SRAM is scattered throughout the die. By analyzing the memory sizes and comparing to the datasheet it might be possible to guess what some of these are for
CMP fill is added to unused areas to keep polishing more even when preparing for the next layer. As such, it looks like it was omitted on M8 (top metal) but is found on other layers
That's all for now. Hope you enjoyed and let me know if you want more information on something!

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I think about this a lot, both in IT and civil infrastructure. It looks so trivial to “fix” from the outside. In fact, it is incredibly draining to do the entirely crushing work of real policy changes internally. It’s harder than drafting a blank page of how the world should be.


I’m at a sort of career crisis point. In my job before, three people could contain the entire complexity of a nation-wide company’s IT infrastructure in their head.

Once you move above that mark, it becomes exponentially, far and away beyond anything I dreamed, more difficult.

And I look at candidates and know-everything’s who think it’s all so easy. Or, people who think we could burn it down with no losses and start over.

God I wish I lived in that world of triviality. In moments, I find myself regretting leaving that place of self-directed autonomy.

For ten years I knew I could build something and see results that same day. Now I’m adjusting to building something in my mind in one day, and it taking a year to do the due-diligence and edge cases and documentation and familiarization and roll-out.

That’s the hard work. It’s not technical. It’s not becoming a rockstar to peers.
These people look at me and just see another self-important idiot in Security who thinks they understand the system others live. Who thinks “bad” designs were made for no reason.
Who wasn’t there.
Recently, the @CNIL issued a decision regarding the GDPR compliance of an unknown French adtech company named "Vectaury". It may seem like small fry, but the decision has potential wide-ranging impacts for Google, the IAB framework, and today's adtech. It's thread time! 👇

It's all in French, but if you're up for it you can read:
• Their blog post (lacks the most interesting details):
https://t.co/PHkDcOT1hy
• Their high-level legal decision: https://t.co/hwpiEvjodt
• The full notification: https://t.co/QQB7rfynha

I've read it so you needn't!

Vectaury was collecting geolocation data in order to create profiles (eg. people who often go to this or that type of shop) so as to power ad targeting. They operate through embedded SDKs and ad bidding, making them invisible to users.

The @CNIL notes that profiling based off of geolocation presents particular risks since it reveals people's movements and habits. As risky, the processing requires consent — this will be the heart of their assessment.

Interesting point: they justify the decision in part because of how many people COULD be targeted in this way (rather than how many have — though they note that too). Because it's on a phone, and many have phones, it is considered large-scale processing no matter what.
"I really want to break into Product Management"

make products.

"If only someone would tell me how I can get a startup to notice me."

Make Products.

"I guess it's impossible and I'll never break into the industry."

MAKE PRODUCTS.

Courtesy of @edbrisson's wonderful thread on breaking into comics –
https://t.co/TgNblNSCBj – here is why the same applies to Product Management, too.


There is no better way of learning the craft of product, or proving your potential to employers, than just doing it.

You do not need anybody's permission. We don't have diplomas, nor doctorates. We can barely agree on a single standard of what a Product Manager is supposed to do.

But – there is at least one blindingly obvious industry consensus – a Product Manager makes Products.

And they don't need to be kept at the exact right temperature, given endless resource, or carefully protected in order to do this.

They find their own way.

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राम-रावण युद्ध समाप्त हो चुका था। जगत को त्रास देने वाला रावण अपने कुटुम्ब सहित नष्ट हो चुका था।श्रीराम का राज्याभिषेक हुआ और अयोध्या नरेश श्री राम के नेतृत्व में चारों दिशाओं में शन्ति थी।
अंगद को विदा करते समय राम रो पड़े थे ।हनुमान को विदा करने की शक्ति तो राम में थी ही नहीं ।


माता सीता भी हनुमान को पुत्रवत मानती थी। अत: हनुमान अयोध्या में ही रह गए ।राम दिनभर दरबार में, शासन व्यवस्था में व्यस्त रहते थे। संध्या को जब शासकीय कार्यों में छूट मिलती तो गुरु और माताओं का कुशल-मंगल पूछ अपने कक्ष में जाते थे। परंतु हनुमान जी हमेशा उनके पीछे-पीछे ही रहते थे ।


उनकी उपस्थिति में ही सारा परिवार बहुत देर तक जी भर बातें करता ।फिर भरत को ध्यान आया कि भैया-भाभी को भी एकांत मिलना चाहिए ।उर्मिला को देख भी उनके मन में हूक उठती थी कि इस पतिव्रता को भी अपने पति का सानिध्य चाहिए ।

एक दिन भरत ने हनुमान जी से कहा,"हे पवनपुत्र! सीता भाभी को राम भैया के साथ एकांत में रहने का भी अधिकार प्राप्त है ।क्या आपको उनके माथे पर सिन्दूर नहीं दिखता?इसलिए संध्या पश्चात आप राम भैया को कृप्या अकेला छोड़ दिया करें "।
ये सुनकर हनुमान आश्चर्यचकित रह गए और सीता माता के पास गए ।


माता से हनुमान ने पूछा,"माता आप अपने माथे पर सिन्दूर क्यों लगाती हैं।" यह सुनकर सीता माता बोलीं,"स्त्री अपने माथे पर सिन्दूर लगाती है तो उसके पति की आयु में वृद्धि होती है और वह स्वस्थ रहते हैं "। फिर हनुमान जी प्रभु राम के पास गए ।
The entire discussion around Facebook’s disclosures of what happened in 2016 is very frustrating. No exec stopped any investigations, but there were a lot of heated discussions about what to publish and when.


In the spring and summer of 2016, as reported by the Times, activity we traced to GRU was reported to the FBI. This was the standard model of interaction companies used for nation-state attacks against likely US targeted.

In the Spring of 2017, after a deep dive into the Fake News phenomena, the security team wanted to publish an update that covered what we had learned. At this point, we didn’t have any advertising content or the big IRA cluster, but we did know about the GRU model.

This report when through dozens of edits as different equities were represented. I did not have any meetings with Sheryl on the paper, but I can’t speak to whether she was in the loop with my higher-ups.

In the end, the difficult question of attribution was settled by us pointing to the DNI report instead of saying Russia or GRU directly. In my pre-briefs with members of Congress, I made it clear that we believed this action was GRU.