BCM2835


11 posts
by red_mamba » Wed Feb 22, 2012 8:55 am
Hi!

I was wondering how were you able to convince Broadcom to give you the datasheet for the SoC? I tried to obtain a datasheet from them for a different chip for a similar project but they refused.

Regards,

David
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by jamesh » Wed Feb 22, 2012 9:13 am
red_mamba said:


Hi!

I was wondering how were you able to convince Broadcom to give you the datasheet for the SoC? I tried to obtain a datasheet from them for a different chip for a similar project but they refused.

Regards,

David


Eben, the Foundation founder, Gert who designed the Gertboard, Dom and myself all work for Broadcom.

However, Eben is the one with the influence! He's also managed to get a decent discount on the chip (which would normally be reserved for very large purchases), and charitable status helps!

Note that the datasheet does not cover the GPU, which, if you were building your own product you would probably need. That's where NDA's and contracts are required  and big sales numbers talk.
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by Gert van Loo » Wed Feb 22, 2012 9:49 am
The data sheet is an combination of four internal documents. It was completely overhauled by me in my spare time and written specific for the Raspberry-Pi foundation. It only describes parts of the design which Broadcom are willing to release based on the fact that they are not seen as IP critical to the companies core competence.
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by cheery » Wed Feb 22, 2012 9:54 am
I hope I can reward them somehow for this.
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by RaTTuS » Wed Feb 22, 2012 10:02 am
you can, by buying lots of devices [not from the first lot though]
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by red_mamba » Thu Feb 23, 2012 2:32 pm
JamesH said:


red_mamba said:


Hi!

I was wondering how were you able to convince Broadcom to give you the datasheet for the SoC? I tried to obtain a datasheet from them for a different chip for a similar project but they refused.

Regards,

David


Eben, the Foundation founder, Gert who designed the Gertboard, Dom and myself all work for Broadcom.

However, Eben is the one with the influence! He's also managed to get a decent discount on the chip (which would normally be reserved for very large purchases), and charitable status helps!

Note that the datasheet does not cover the GPU, which, if you were building your own product you would probably need. That's where NDA's and contracts are required  and big sales numbers talk.


I'm working with BCM5354 :)

Well at least I try to ;)
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by jamesh » Thu Feb 23, 2012 2:54 pm
cheery said:


I hope I can reward them somehow for this.


Actually, I've been known to work for beer.
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by jamesh » Thu Feb 23, 2012 2:56 pm
red_mamba said:





I'm working with BCM5354 :)

Well at least I try to ;)


That one is nothing to do with us!
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by red_mamba » Thu Feb 23, 2012 3:09 pm
JamesH said:


red_mamba said:





I'm working with BCM5354 :)

Well at least I try to ;)


That one is nothing to do with us!


Depends how you look at it.

It's a broadcom SoC, but yes it doesn't has anything to do with RPi.

I newer said it did :)
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by jamesh » Thu Feb 23, 2012 4:13 pm
red_mamba said:


JamesH said:


red_mamba said:





I'm working with BCM5354 :)

Well at least I try to ;)


That one is nothing to do with us!


Depends how you look at it.

It's a broadcom SoC, but yes it doesn't has anything to do with RPi.

I newer said it did :)


Broadcom has offices all over the world, lots of different departments. The part that did the SoC on the Pi (of which the people who post here are all part of) won't even have heard of this device! That's the way to look at it.
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by ridge » Tue Mar 06, 2012 6:49 pm
Gert,

A sincere thank you for making what specs are available for the BCM2835 public.

Am I wrong in assuming that no more are forthcoming?

Chip manufacturers usually fall all over themselves to make data sheets available.

It's very strange to have to plead for data sheets...

OK, here goes - "Please, sir, I want some more."
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