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by bstrobl
Fri Sep 11, 2015 9:25 am
Forum: General discussion
Topic: Why didn't we go with Mali?
Replies: 139
Views: 20116

Re: Why didn't we go with Mali?

Mostly SW engineers rather than HW/chip designers at RPF. I work with a couple of ex-Brcm HW engineers (in fact the whole office is ex-Brcm) - we are all in the vicinity!! So all the improvements done to make the 2836 were pretty much made only by Broadcom? Seemed like a collaborative project with ...
by bstrobl
Fri Sep 11, 2015 8:47 am
Forum: General discussion
Topic: Why didn't we go with Mali?
Replies: 139
Views: 20116

Re: Why didn't we go with Mali?

Why don't we just add a R9 295 x2 :D Won't fit into a small case anymore :D Would it be possible to create a VC4+ by tacking on more QPUs or would that require massive changes/design work? That would cost a couple of million dollars. Seems like a bargain, amortised over several years and a couple o...
by bstrobl
Thu Sep 10, 2015 10:10 pm
Forum: General discussion
Topic: Why didn't we go with Mali?
Replies: 139
Views: 20116

Re: Why didn't we go with Mali?

zeth wrote:For what its worth (nothing), I would rather any future RPI 2+ in 2020 to have this, graphics performance is already fine (for me).
I won't rest till I have my Raspi Model C with 2 VC4s frankensteined together for twice the performance :lol:
by bstrobl
Thu Sep 10, 2015 3:50 pm
Forum: General discussion
Topic: Why didn't we go with Mali?
Replies: 139
Views: 20116

Re: Why didn't we go with Mali?

That would cost a couple of million dollars. If there was anyone left at Broadcom with the knowhow. Not saying it won;t be done - just giving an indication of the scale of the work. I know nothing of Vulcan. Note, that adding QPU's doesn't necessarily increase the overall performance. For example, ...
by bstrobl
Thu Sep 10, 2015 2:20 pm
Forum: General discussion
Topic: Why didn't we go with Mali?
Replies: 139
Views: 20116

Re: Why didn't we go with Mali?

At the time of development (8 or more years ago), the Videocore 3 then 4, they were more powerful than the Mali. In addition, the videocore includes a camera ISP, LCD drivers etc, which the Mali does not. Also, the VC uses less power for the same performance, which was important for the mobile spac...
by bstrobl
Tue Sep 01, 2015 12:32 pm
Forum: Astro Pi
Topic: Astro Pi Temperature Sensor Reading
Replies: 63
Views: 36332

Re: Astro Pi Temperature Sensor Reading

This doesn't take into account rotation and stuff. However, I've been working on a formula this evening. In my experience, AmbientTemp - ( (CPUtemp - AmbientTemp) / 2 ) is accurate to within a degree or two. Hope this helps someone! Here is the python code for those who have the same issue: #!/usr/...
by bstrobl
Fri Aug 28, 2015 11:19 am
Forum: General discussion
Topic: Usb Type-C
Replies: 45
Views: 18465

Re: Usb Type-C

In answer to the original question, AFAIK, there are no plans to make a USB Type C Pi at this stage. The technology is too expensive to incorporate at the moment (for reasons outlined above), which goes against the ethos of a cheap educational device. As for the more distant future? Who knows. Once...
by bstrobl
Thu Aug 27, 2015 7:23 pm
Forum: General discussion
Topic: Usb Type-C
Replies: 45
Views: 18465

Re: Usb Type-C

If it costs thousands of dollars to integrate then why didnt the Mac AirBook go up in price, or the chromebook. Intel provides them with a USB 3.0 Controller in the Platform Controller Hub of each Intel Chipset since Ivy Bridge. If were were making the first gen SoC as a prototype I could see it co...
by bstrobl
Thu Aug 27, 2015 6:33 pm
Forum: General discussion
Topic: Usb Type-C
Replies: 45
Views: 18465

Re: Usb Type-C

We appear to have a comprehension breakdown between responses. Basic fact USB TYPE-C will only be feasible if the LAN9514 Chipset is replaced afaica As there is at present no suitable Chipset, therefore in the forseeable future. USB TYPE-C will not be implemented. Actually Type-C can be implemented...
by bstrobl
Thu Aug 27, 2015 6:32 pm
Forum: General discussion
Topic: Usb Type-C
Replies: 45
Views: 18465

Re: Usb Type-C

I have only said it is required for me. Again all I asked is if there is talk about adding it. And if you want to be technical type-c is only the connection and easily be setup to run on usb 2.0 as a previous post pointed out. And I am not looking at Usb 3.0 I am talking about USB 3.1. You cannot c...
by bstrobl
Thu Aug 27, 2015 6:17 pm
Forum: General discussion
Topic: Usb Type-C
Replies: 45
Views: 18465

Re: Usb Type-C

Thanks, for the link I found it late last night. As far as using proven technology isn't that just a cop out. It is a prototyping board. Designed to make projects quick and test things out. Test ideas in a cheaper environment. Build things using modern technology. usb 2.0 is not modern and has been...
by bstrobl
Thu Aug 27, 2015 8:05 am
Forum: General discussion
Topic: Usb Type-C
Replies: 45
Views: 18465

Re: Usb Type-C

While it is possible to implement Type-C on a USB 2.0 device there is not much point in doing so: 1. USB 3.1 (5Gbps/10Gbps) Speeds are not supported by the SoC. 2. Power Delivery is not supported due to the low power support of the whole board, hence nothing more than 5V and 1A per port. 3. Most dev...
by bstrobl
Wed Aug 19, 2015 4:05 pm
Forum: General discussion
Topic: What is the most reliable micro-sd card I can buy?
Replies: 7
Views: 2438

Re: What is the most reliable micro-sd card I can buy?

Just purchased myself a Sandisk High Endurance card. According to my calculations it should sustain around 50 Terabytes of writes (100 for the 64 GB version). Might be something to look into if you are heavy on writes and have a stable power supply.
by bstrobl
Fri May 29, 2015 9:04 pm
Forum: Off topic discussion
Topic: Quote without comment... [Avagos / Broadcom takeover rumour]
Replies: 50
Views: 3630

Re: Quote without comment... [Avagos / Broadcom takeover rum

Is this still the thread about Avago buys Broadcom? The deal seems to be perfect. So it's not an rumour anymore. Or is it about chip specifications? I'm realy interested in the impact of this deal for the future of the Raspberry Pi, if there is any. (I mean impact, not the future ;) ) So can you te...
by bstrobl
Fri May 29, 2015 11:57 am
Forum: Off topic discussion
Topic: Quote without comment... [Avagos / Broadcom takeover rumour]
Replies: 50
Views: 3630

Re: Quote without comment... [Avagos / Broadcom takeover rum

The RPi has always been able to address 1GB, unfortunately no one manufacturs 1GB PoP for the BCM2835. With the change to BCM2836 a "standard" 1GB Memory Chip could be used. This is not correct, the Pi2 still uses a PoP style memory chip even though it's not mounted in PoP The RPF managed to convin...
by bstrobl
Fri May 29, 2015 10:05 am
Forum: Off topic discussion
Topic: Quote without comment... [Avagos / Broadcom takeover rumour]
Replies: 50
Views: 3630

Re: Quote without comment... [Avagos / Broadcom takeover rum

The RPi has always been able to address 1GB, unfortunately no one manufacturs 1GB PoP for the BCM2835. With the change to BCM2836 a "standard" 1GB Memory Chip could be used. This is not correct, the Pi2 still uses a PoP style memory chip even though it's not mounted in PoP The RPF managed to convin...
by bstrobl
Fri May 29, 2015 9:23 am
Forum: Off topic discussion
Topic: Quote without comment... [Avagos / Broadcom takeover rumour]
Replies: 50
Views: 3630

Re: Quote without comment... [Avagos / Broadcom takeover rum

Nope to floor plans. As to the change, apart from some bug fixing, it's simply the removal of the Armv11 and replacing it with 4xA7's with a consequent increase in die size. The GPU was untouched AFAIK. Where can I get a list of these bugs that have been fixed? And one last question, how does the B...
by bstrobl
Fri May 29, 2015 9:07 am
Forum: Off topic discussion
Topic: Quote without comment... [Avagos / Broadcom takeover rumour]
Replies: 50
Views: 3630

Re: Quote without comment... [Avagos / Broadcom takeover rum

Well, the actual figures are clearly Brcm confidential, but ballpark figures should give some idea. It does depend on the particular licence a company has with ARM. Brcm have an ARM A7 licence so they wouldn't need to buy another one (that's going to be a couple $M at least), so that just leaves de...
by bstrobl
Fri May 29, 2015 8:50 am
Forum: Off topic discussion
Topic: Quote without comment... [Avagos / Broadcom takeover rumour]
Replies: 50
Views: 3630

Re: Quote without comment... [Avagos / Broadcom takeover rum

Just checked up with people who know this stuff - cost of moving an SoC to USB3.0 would be v. expensive, in the multi $100k's, in addition to whatever else you are doing to the chip. How much did it cost to get the BCM2836 done? Getting it to run with the first batch of silicon along with the conse...
by bstrobl
Wed Feb 04, 2015 11:59 am
Forum: General discussion
Topic: The Raspberry Pi 2 Q&A thread
Replies: 442
Views: 95459

Re: The Raspberry Pi 2 Q&A thread

I asked this on the main page blog posting, but it's gone unanswered: Is the BCM2836 made with the same process as the 2835 (width, silicon, doping etc)? I'm curious as to how you've made it clock faster. I remember Dom saying the foundry had tweaked things in favour of speed at the expense of powe...

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