Hello,
So I was browsing the FreedomBox mailing list when I saw a mention of a plug computer being crowdfunded:
http://lists.alioth.debian.org/pipermail/freedombox-discuss/2015- September/006879.html
Here's the actual crowdfunding page:
https://www.kickstarter.com/projects/1547898916/own-mailbox-the-first-100- confidential-mailbox
And the home page of the device:
So, it seems that the initiators of the campaign have made their own Allwinner A13 board with 256MB RAM and Ethernet support. It is open hardware, apparently, and the software is Free Software, not some kind of proprietary "snake oil" that some privacy campaigns tend to foist on their supporters.
It is a bit odd that they've decided to go their own way with the hardware, though. The FreedomBox recommends existing hardware rather than focusing on one particular device:
https://wiki.debian.org/FreedomBox/Hardware
Another initiative just uses one of the Olimex A20-based products:
Where the product in question looks a lot more capable than the one attempting to be funded above:
https://www.olimex.com/Products/OLinuXino/A20/A20-OLinuXino-LIME/open-source... hardware
Anyway, back to EOMA-68, and a quick search produced a page on the plug computer idea for EOMA-68:
http://rhombus-tech.net/community_ideas/plug_computer/
It occurred to me that if only we had EOMA-68 boards out there, maybe people wouldn't be so enthusiastic to go to the trouble of making new boards and running the gauntlet of crowdfunding. There also wouldn't be the artificiality of "stretch goals" where things that should just be happening anyway are punted off into an uncertain future, dependent on the delivery of something that should be separate.
Paul
On Mon, Sep 14, 2015 at 4:47 PM, Paul Boddie paul@boddie.org.uk wrote:
Hello,
So I was browsing the FreedomBox mailing list when I saw a mention of a plug computer being crowdfunded:
http://lists.alioth.debian.org/pipermail/freedombox-discuss/2015- September/006879.html
Here's the actual crowdfunding page:
https://www.kickstarter.com/projects/1547898916/own-mailbox-the-first-100- confidential-mailbox
And the home page of the device:
looks great!
So, it seems that the initiators of the campaign have made their own Allwinner A13 board with 256MB RAM and Ethernet support. It is open hardware, apparently, and the software is Free Software, not some kind of proprietary "snake oil" that some privacy campaigns tend to foist on their supporters.
goooood.
It is a bit odd that they've decided to go their own way with the hardware, though.
well, if it's libre hardware then that's good, i hope!
Anyway, back to EOMA-68, and a quick search produced a page on the plug computer idea for EOMA-68:
http://rhombus-tech.net/community_ideas/plug_computer/
It occurred to me that if only we had EOMA-68 boards out there, maybe people wouldn't be so enthusiastic to go to the trouble of making new boards and running the gauntlet of crowdfunding.
i knooooow :)
here's the thing though:
(1) i have to get the standard right for a 10-year-old and greater period (2) i have to get CPU Cards (plural) designed, sponsored, and tested (3) i have to prove that it is, indeed, simpler and lower-cost to make carrier boards.
so that's what i'm doing.
to explain, first: this project has an absolute top priority of being *right* (defined as "viable long-term") over being "rushed to profitability".
second: it's no good having just the one CPU Card out there. people won't comprehend the modularity concept if there is only the additional cost of having a single processor available.
third: even i was unable to move the micro-desktop board (which is only 4in x 4.5in) forward because i had designed it as a 4-layer PCB - costs are around $400 for qty 5 4-layer prototype boards on a 3 week turnaround by complete contrast, a 7-day turnaround for qty 5 2-layer prototype (bare copper) boards with larger vias is around $40 for qty 2, and around $100 for qty 5.
so.... it's getting there, paul.
l.
On Tue, Sep 15, 2015 at 1:18 PM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
[...] even i was unable to move the micro-desktop board (which is only 4in x 4.5in) forward because i had designed it as a 4-layer PCB - costs are around $400 for qty 5 4-layer prototype boards on a 3 week turnaround by complete contrast, a 7-day turnaround for qty 5 2-layer prototype (bare copper) boards with larger vias is around $40 for qty 2, and around $100 for qty 5.
Imbecile question: is it at all reasonably possible to redesign the micro-desktop board to be a 2-layer board?
On Tue, Sep 15, 2015 at 7:22 PM, Christopher Havel laserhawk64@gmail.com wrote:
On Tue, Sep 15, 2015 at 1:18 PM, Luke Kenneth Casson Leighton < lkcl@lkcl.net> wrote:
[...] even i was unable to move the micro-desktop board (which is only 4in x 4.5in) forward because i had designed it as a 4-layer PCB - costs are around $400 for qty 5 4-layer prototype boards on a 3 week turnaround by complete contrast, a 7-day turnaround for qty 5 2-layer prototype (bare copper) boards with larger vias is around $40 for qty 2, and around $100 for qty 5.
Imbecile question: is it at all reasonably possible to redesign the micro-desktop board to be a 2-layer board?
If board have high speed design it is very unlikely that you can do it properly (because you have to be careful about routing to ground, you have many lines that you have to match etc etc and when you have only 2 layers it is difficult to keep it all correct). In theory maybe it could be possible but it is a hell of a work and then you risk a lot that PCB will not be good.
arm-netbook mailing list arm-netbook@lists.phcomp.co.uk http://lists.phcomp.co.uk/mailman/listinfo/arm-netbook Send large attachments to arm-netbook@files.phcomp.co.uk
On Tue, Sep 15, 2015 at 6:41 PM, Hrvoje Lasic lasich@gmail.com wrote:
On Tue, Sep 15, 2015 at 7:22 PM, Christopher Havel laserhawk64@gmail.com wrote:
On Tue, Sep 15, 2015 at 1:18 PM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
[...] even i was unable to move the micro-desktop board (which is only 4in x 4.5in) forward because i had designed it as a 4-layer PCB - costs are around $400 for qty 5 4-layer prototype boards on a 3 week turnaround by complete contrast, a 7-day turnaround for qty 5 2-layer prototype (bare copper) boards with larger vias is around $40 for qty 2, and around $100 for qty 5.
Imbecile question: is it at all reasonably possible to redesign the micro-desktop board to be a 2-layer board?
If board have high speed design it is very unlikely that you can do it properly (because you have to be careful about routing to ground, you have many lines that you have to match etc etc and when you have only 2 layers it is difficult to keep it all correct). In theory maybe it could be possible but it is a hell of a work and then you risk a lot that PCB will not be good.
i took a look at a gigabit ethernet board that phil kindly sent me a while back. the layout of the differential pairs was absolutely fascinating [and the board had, obviously, passed FCC tests].
the layout involved putting ground vias exactly... something like 20mil from the differential pairs, spaced out at exactly something like... 100mil, right the way *both* sides. there were no components permitted either side for some distance either. there were no vias in the actual differential pairs, either.
there were twenty sets of differential pairs like this - all with exactly the same very very clearly and meticulously laid out arrangement, with the spacing between each differential pair also very meticulously laid out.
so it can be done.
in the micro-desktop board, however, the actual distance that the USB differential pairs has to travel is well under 1cm. i am arranging the connectors *directly* in front of where the signals come out. i have also deliberately arranged the EOMA68 interface so that the pairs come out directly and do not require a via to "cross over" each other.
so it is much less of a concern than might otherwise normally be. these aren't 10cm traces, where EM radiation would definitely be a major concern, they're literally 1cm long, and i intend to surround them with ground vias.
of slightly more concern is the VGA interface (RGB/TTL being converted to analogue), which will be operating at around 75mhz (or so). however that's not 480mhz, so i am not hugely concerned. i am again getting in as many GND vias as can fit, and keeping the traces very very short. the buffer ICs actually straddle the PCMCIA interface on the other side of the board, so that the RGB/TTL signals can, with vias, go left or right, routing as appropriate, maximum trace length about... 3mm.
l.
On Wed, Sep 16, 2015 at 3:41 AM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
On Tue, Sep 15, 2015 at 6:41 PM, Hrvoje Lasic lasich@gmail.com wrote:
On Tue, Sep 15, 2015 at 7:22 PM, Christopher Havel <
laserhawk64@gmail.com>
wrote:
On Tue, Sep 15, 2015 at 1:18 PM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
[...] even i was unable to move the micro-desktop board (which is only 4in x 4.5in) forward because i had designed it as a 4-layer PCB - costs are around $400 for qty 5 4-layer prototype boards on a 3 week turnaround by complete contrast, a 7-day turnaround for qty 5 2-layer prototype (bare copper) boards with larger vias is around $40 for qty 2, and around $100 for qty 5.
Imbecile question: is it at all reasonably possible to redesign the micro-desktop board to be a 2-layer board?
If board have high speed design it is very unlikely that you can do it properly (because you have to be careful about routing to ground, you
have
many lines that you have to match etc etc and when you have only 2
layers it
is difficult to keep it all correct). In theory maybe it could be
possible
but it is a hell of a work and then you risk a lot that PCB will not be good.
i took a look at a gigabit ethernet board that phil kindly sent me a while back. the layout of the differential pairs was absolutely fascinating [and the board had, obviously, passed FCC tests].
the layout involved putting ground vias exactly... something like 20mil from the differential pairs, spaced out at exactly something like... 100mil, right the way *both* sides. there were no components permitted either side for some distance either. there were no vias in the actual differential pairs, either.
there were twenty sets of differential pairs like this - all with exactly the same very very clearly and meticulously laid out arrangement, with the spacing between each differential pair also very meticulously laid out.
so it can be done.
in the micro-desktop board, however, the actual distance that the USB differential pairs has to travel is well under 1cm. i am arranging the connectors *directly* in front of where the signals come out. i have also deliberately arranged the EOMA68 interface so that the pairs come out directly and do not require a via to "cross over" each other.
so it is much less of a concern than might otherwise normally be. these aren't 10cm traces, where EM radiation would definitely be a major concern, they're literally 1cm long, and i intend to surround them with ground vias.
of slightly more concern is the VGA interface (RGB/TTL being converted to analogue), which will be operating at around 75mhz (or so). however that's not 480mhz, so i am not hugely concerned. i am again getting in as many GND vias as can fit, and keeping the traces very very short. the buffer ICs actually straddle the PCMCIA interface on the other side of the board, so that the RGB/TTL signals can, with vias, go left or right, routing as appropriate, maximum trace length about... 3mm.
anyway, absolutely amazing work to fit it all like you described.
l.
arm-netbook mailing list arm-netbook@lists.phcomp.co.uk http://lists.phcomp.co.uk/mailman/listinfo/arm-netbook Send large attachments to arm-netbook@files.phcomp.co.uk
On Wed, Sep 16, 2015 at 5:28 AM, Hrvoje Lasic lasich@gmail.com wrote:
anyway, absolutely amazing work to fit it all like you described.
the complexity of that kind of 2-layer layout was one (unspoken) reason why i took off ethernet. yehh, we'll see what happens, neh? :)
l.
On Tue, Sep 15, 2015 at 6:22 PM, Christopher Havel laserhawk64@gmail.com wrote:
On Tue, Sep 15, 2015 at 1:18 PM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
[...] even i was unable to move the micro-desktop board (which is only 4in x 4.5in) forward because i had designed it as a 4-layer PCB - costs are around $400 for qty 5 4-layer prototype boards on a 3 week turnaround by complete contrast, a 7-day turnaround for qty 5 2-layer prototype (bare copper) boards with larger vias is around $40 for qty 2, and around $100 for qty 5.
Imbecile question: is it at all reasonably possible to redesign the micro-desktop board to be a 2-layer board?
yes, i've done it already. i do have to increase the via sizes from 10mil + a 20mil surround to 12mil + a 24mil surround to fit the rules of a lower-cost PCB factory that i know of, but other than that, it's done already.
l.
On Tuesday 15. September 2015 19.18.26 Luke Kenneth Casson Leighton wrote:
On Mon, Sep 14, 2015 at 4:47 PM, Paul Boddie paul@boddie.org.uk wrote:
It occurred to me that if only we had EOMA-68 boards out there, maybe people wouldn't be so enthusiastic to go to the trouble of making new boards and running the gauntlet of crowdfunding.
i knooooow :)
here's the thing though:
(1) i have to get the standard right for a 10-year-old and greater period (2) i have to get CPU Cards (plural) designed, sponsored, and tested (3) i have to prove that it is, indeed, simpler and lower-cost to make carrier boards.
so that's what i'm doing.
to explain, first: this project has an absolute top priority of being *right* (defined as "viable long-term") over being "rushed to profitability".
Sure, I understand that. But what worries me a little is that experience isn't being gained to possibly refine the standard or develop for it. Of course, I'm writing this with only a superficial knowledge of what has gone on in the past, and it is possible that people have done things with previously-produced hardware that has informed the effort.
second: it's no good having just the one CPU Card out there. people won't comprehend the modularity concept if there is only the additional cost of having a single processor available.
I understand this, too. It's also useful to have different devices they can be used in as well, and I worry that these won't come about without any cards being available.
One thing in the back of my mind (and part of a long list of things that I could consider doing) is helping to design such a device, and for that I suppose I need to collect links to documentation that might help me get started.
third: even i was unable to move the micro-desktop board (which is only 4in x 4.5in) forward because i had designed it as a 4-layer PCB - costs are around $400 for qty 5 4-layer prototype boards on a 3 week turnaround by complete contrast, a 7-day turnaround for qty 5 2-layer prototype (bare copper) boards with larger vias is around $40 for qty 2, and around $100 for qty 5.
so.... it's getting there, paul.
Yes, prototyping gets expensive for advanced stuff, I suppose, and since we're not part of the normal industrial operations that can do this efficiently (in terms of costs and other things), we're at a disadvantage.
Still, I wonder what those of us reading this list might be able to do to move the effort forward in our own way.
Paul
On Wed, Sep 16, 2015 at 11:49 PM, Paul Boddie paul@boddie.org.uk wrote:
On Tuesday 15. September 2015 19.18.26 Luke Kenneth Casson Leighton wrote:
On Mon, Sep 14, 2015 at 4:47 PM, Paul Boddie paul@boddie.org.uk wrote:
It occurred to me that if only we had EOMA-68 boards out there, maybe people wouldn't be so enthusiastic to go to the trouble of making new boards and running the gauntlet of crowdfunding.
i knooooow :)
here's the thing though:
(1) i have to get the standard right for a 10-year-old and greater period (2) i have to get CPU Cards (plural) designed, sponsored, and tested (3) i have to prove that it is, indeed, simpler and lower-cost to make carrier boards.
so that's what i'm doing.
to explain, first: this project has an absolute top priority of being *right* (defined as "viable long-term") over being "rushed to profitability".
Sure, I understand that. But what worries me a little is that experience isn't being gained to possibly refine the standard
paul, you misunderstand the concept of a simple long-term standard. it goes from "being developed and refined" to "absolutely locked irrevocably without fail absolute without fail absolute 100% in stone" with no phase in between.
once there are any end-users out there, there *is* no "second chance". that's *IT*. i cannot make that complex enough to be understood and accepted.
the reasons why there are no second chances are clearly laid out in the white paper i wrote.
so, the opportunity, if anyone wants to get involved with "refinement" of the standard, that's what they've had over the past four years, and now it's almost over. they can talk to me, they can read the white paper (in which i describe the justification of the interface selection), and they can try to argue for additions or changes, but right now the window of opportinity to do that is closing, as i am about to send off two CPU Cards with the latest (last) revisions.
anyone beyond that point in about 10-14 days time, if they want modifications to the standard, it had better come with a cheque for $5,000 attached to it in order to repay both my clients for the samples that will have been made by that time.
or develop for it.
that's straightforward "critical mass", which comes once the standard's finalised, first products out the door, etc. etc.
Of course, I'm writing this with only a superficial knowledge of what has gone on in the past, and it is possible that people have done things with previously-produced hardware that has informed the effort.
http://rhombus-tech.net/allwinner_a10/news/
that's a brief timeline for the a10 cpu card (which became the a20 cpu card). the standard has been revised about... i think it's three times since then, maybe four.
first revision was to remove SATA and replace it with a 2nd USB2. second revision was to add VREFTTL, add SD/MMC and UART, third (or possibly still part of the 2nd) was to reduce 24-pin RGB/TTL to 18-pin RGB/TTL and use the 4 spare lines for an SPI interface, also USB3 was added at some point. PWM and an extra EINT were also added. the fourth - and almost certainly final revision - has been very recent: removal of Ethernet, upgrading to being able to do USB 3.1, as well as add 2 more EINT lines and 3 more GPIOs.
those interfaces have all been very carefully considered, especially when developing the ICubeCorp IC3128 CPU Card, where, due to its low pincount and being a QFP, there's *literally* only 2 spare unused pins left on the *entire* processor that don't go to the EOMA68 interface or the SD/MMC boot card.
second: it's no good having just the one CPU Card out there. people won't comprehend the modularity concept if there is only the additional cost of having a single processor available.
I understand this, too. It's also useful to have different devices they can be used in as well, and I worry that these won't come about without any cards being available.
that's why i'm doing more than one product - micro-desktop as well as the laptop. i've actually designed around... 5 or 6 different products, all at different stages. the tablet is "on hold" because of lack of interest [and, because it's a complex and dense 4-layer board it's going to be tough converting it to 2-layer]. the 15in laptop is sponsored so that's ok. and the micro-desktop, what with the PCB now being 2-layer, is actually low-cost enough for me to put together a new revision on a very low budget.
irony is all these will probably hit all at the same time.
One thing in the back of my mind (and part of a long list of things that I could consider doing)
:)
is helping to design such a device, and for that I suppose I need to collect links to documentation that might help me get started.
honestly, finding the parts (ones that are affordable, not end-of-life, or fell off the back of a lorry and i do mean that literally, even though they had to have a bit of a push to fall of....) and/or finding the contacts _willing_ to source the parts - that's the hardest bit of the entire job of designing any board.
oh. that and, of course, being able to get hold of the damn datasheets.
one cool product that would be awesome to have would be a 3d printer controller that took an EOMA68 CPU Card. in some ways this would be a bodge-job of taking a libre-hardware-licensed PCB design, expanding its size a bit and connecting 5V power and USB up to the on-board USB interface of the Micro-Controller.
that way you would have the actual computer *on* the same board that had the (usually unreliable) power line... the one that gets spiked due to 50hz mains fluctuations and lack of proper earth loops associated with USB cables,500 watt PSUs, and amateur-designed PCBs.
a second cool product would be a robotics platform / educational platform.
another would be to track down a suitable libre-toolchain FPGA and make a CPU Card out of it. i heard that someone has actually managed to reverse-engineer one of the commonly-available FPGAs, to the point where the toolchain is stable. saw an article about it recently. that _would_ be awesome.
third: even i was unable to move the micro-desktop board (which is only 4in x 4.5in) forward because i had designed it as a 4-layer PCB - costs are around $400 for qty 5 4-layer prototype boards on a 3 week turnaround by complete contrast, a 7-day turnaround for qty 5 2-layer prototype (bare copper) boards with larger vias is around $40 for qty 2, and around $100 for qty 5.
so.... it's getting there, paul.
Yes, prototyping gets expensive for advanced stuff, I suppose, and since we're not part of the normal industrial operations that can do this efficiently (in terms of costs and other things), we're at a disadvantage.
Still, I wonder what those of us reading this list might be able to do to move the effort forward in our own way.
that would be great.
On 17/09/15 00:34, Luke Kenneth Casson Leighton wrote:
that's why i'm doing more than one product - micro-desktop as well as the laptop. i've actually designed around... 5 or 6 different products, all at different stages. the tablet is "on hold" because of lack of interest [and, because it's a complex and dense 4-layer board it's going to be tough converting it to 2-layer]. the 15in laptop is sponsored so that's ok. and the micro-desktop, what with the PCB now being 2-layer, is actually low-cost enough for me to put together a new revision on a very low budget.
awww :( ive been looking forward to the tablet, in fact ive been holding out the last 4 years cus i wanted my first tablet to be a eoma one :D.
i guess lack of interest means lack of funds given to help make it... :/ hmmm...
but yea, i look forward so much to buying the eoma(-68) laptop, the eoma micro-desktop, eoma tablet, heck and maybe even the eoma games console! the eoma-68 collection! yum yum!
im interested in the games console and think its brilliant that theres a team working on a eoma-68 one :D, but i dont play games to so much these days... ill guess ill see how much it all adds up to in the shopping basket at the time hehe. Those past cad renders i thought looked really cool btw. looking forward to seeing how it looks now. been wondering what state its at lately.
i do love reading your posts luke. i find them a great read. I even loled at the bit about the parts falling off the lorry :D
On Thu, Sep 17, 2015 at 2:04 AM, Alexander Stephen Thomas Ross maillist_arm-netbook@aross.me wrote:
On 17/09/15 00:34, Luke Kenneth Casson Leighton wrote:
that's why i'm doing more than one product - micro-desktop as well as the laptop. i've actually designed around... 5 or 6 different products, all at different stages. the tablet is "on hold" because of lack of interest [and, because it's a complex and dense 4-layer board it's going to be tough converting it to 2-layer]. the 15in laptop is sponsored so that's ok. and the micro-desktop, what with the PCB now being 2-layer, is actually low-cost enough for me to put together a new revision on a very low budget.
awww :( ive been looking forward to the tablet, in fact ive been holding out the last 4 years cus i wanted my first tablet to be a eoma one :D.
i guess lack of interest means lack of funds given to help make it... :/ hmmm...
remember the "or" there - ooorrr i redesign it to be 2-layer, in which case it's no longer $600 for 5 PCBs but is something like... $100 for 5 PCBs. the only problem being, they'd be 1.5mm thick prototype PCBs, not the 1.2mm that the casework is designed for.
but yea, i look forward so much to buying the eoma(-68) laptop, the eoma micro-desktop, eoma tablet, heck and maybe even the eoma games console! the eoma-68 collection! yum yum!
:)
im interested in the games console and think its brilliant that theres a team working on a eoma-68 one :D, but i dont play games to so much these days...
well that's ok, because as you can see from the scenarios section of the white paper, and from the whole eoma68 concept, it's rather plainly obvious that "an eoma68 games console" is NOT just "a games console".
i do love reading your posts luke. i find them a great read. I even loled at the bit about the parts falling off the lorry :D
haha goood :)
On Thursday 17. September 2015 01.34.15 Luke Kenneth Casson Leighton wrote:
On Wed, Sep 16, 2015 at 11:49 PM, Paul Boddie paul@boddie.org.uk wrote:
Sure, I understand that. But what worries me a little is that experience isn't being gained to possibly refine the standard
paul, you misunderstand the concept of a simple long-term standard.
Not really. What I meant by "refined" is actually this:
[...]
first revision was to remove SATA and replace it with a 2nd USB2. second revision was to add VREFTTL, add SD/MMC and UART, third (or possibly still part of the 2nd) was to reduce 24-pin RGB/TTL to 18-pin RGB/TTL and use the 4 spare lines for an SPI interface, also USB3 was added at some point. PWM and an extra EINT were also added. the fourth - and almost certainly final revision - has been very recent: removal of Ethernet, upgrading to being able to do USB 3.1, as well as add 2 more EINT lines and 3 more GPIOs.
those interfaces have all been very carefully considered, especially when developing the ICubeCorp IC3128 CPU Card, where, due to its low pincount and being a QFP, there's *literally* only 2 spare unused pins left on the *entire* processor that don't go to the EOMA68 interface or the SD/MMC boot card.
All of this has happened before we get to the point where we call it a final standard, but what worries me is that there may be an application that hasn't yet been considered because the collective experience of trying to make devices using it is not broad enough.
I must admit that this is coloured by my interests in "retrocomputing" where one can look at products that were made and then consider how they might have been improved, even by a small amount, in a way that might have made them a lot more successful. At the time, you'd have some company or other designing and manufacturing their products to a tight schedule (usually to hit the market at the best time of year), but there would be limitations discovered by the customers that would limit the competitive lifetime of the product.
In any case, from what you've written, I guess we'll find out for ourselves soon enough about how successful the refinement process has been. Not that I think that it hasn't been successful enough, however.
[...]
Still, I wonder what those of us reading this list might be able to do to move the effort forward in our own way.
that would be great.
Any suggestions? :-)
Paul
On Thu, Sep 17, 2015 at 12:04 PM, Paul Boddie paul@boddie.org.uk wrote:
On Thursday 17. September 2015 01.34.15 Luke Kenneth Casson Leighton wrote:
On Wed, Sep 16, 2015 at 11:49 PM, Paul Boddie paul@boddie.org.uk wrote:
Sure, I understand that. But what worries me a little is that experience isn't being gained to possibly refine the standard
paul, you misunderstand the concept of a simple long-term standard.
Not really. What I meant by "refined" is actually this:
[...]
first revision was to remove SATA and replace it with a 2nd USB2. second revision was to add VREFTTL, add SD/MMC and UART, third (or possibly still part of the 2nd) was to reduce 24-pin RGB/TTL to 18-pin RGB/TTL and use the 4 spare lines for an SPI interface, also USB3 was added at some point. PWM and an extra EINT were also added. the fourth - and almost certainly final revision - has been very recent: removal of Ethernet, upgrading to being able to do USB 3.1, as well as add 2 more EINT lines and 3 more GPIOs.
those interfaces have all been very carefully considered, especially when developing the ICubeCorp IC3128 CPU Card, where, due to its low pincount and being a QFP, there's *literally* only 2 spare unused pins left on the *entire* processor that don't go to the EOMA68 interface or the SD/MMC boot card.
All of this has happened before we get to the point where we call it a final standard, but what worries me is that there may be an application that hasn't yet been considered because the collective experience of trying to make devices using it is not broad enough.
well, as well as the section on the elinux.org web site analysing and tracking half a dozen different standards and their limitations, that's what the section on "interfaces" in the white paper is for, to go through the past (several decades of computing), learn from it, predict where it's going, track that for 4 years, adjust the tracking to make sure it fits, then re-predict, re-confirm, re-track and then at some point say "ok done".
it's precisely the knowledge of prior failed standards, paul, that's kept me from going, like a drunken naive wannab computaa n00b "okaay yeahh i wanna do a standurd now, let's put some inturfaciz in 4 fun, make some lolli y not?" - translating that into english it reads "create something then throw it out the door in under a year and hope it works" *NO*.
i recommend reading the sections on the white paper covering the standard's development and justification (so that i don't have to repeat it here) because i go into some depth to justify each of the decisions that are made, including analysing and demonstrating how long they've each been around, and how long they are likely to stay around.
I must admit that this is coloured by my interests in "retrocomputing" where one can look at products that were made and then consider how they might have been improved, even by a small amount, in a way that might have made them a lot more successful.
well then, you would enjoy the anecdotes that i included in the white paper, which include some historical and hilarious examples of exactly that.
At the time, you'd have some company or other designing and manufacturing their products to a tight schedule (usually to hit the market at the best time of year), but there would be limitations discovered by the customers that would limit the competitive lifetime of the product.
... or in the case of standards, not enough thought went into them, so they cause utter confusion and mental melt-down in the minds of adopters. i am not joking but the only decent standards which do not cause such complete melt-down are COM-Express and PC-104. there's no "optionalitis" in those standards (except COM-Express module sizes, and that's ok).
.... https://en.wikipedia.org/wiki/PC/104#Potential_Compatibility_Issues aaargh noooo, PC-104 is.... arg. of course, because it's based around the IBM PC which of course needs 12v, 5v and 3.3v, it's all gone tits-up thanks to some carrier boards not properly supplying all the required voltages, so the CPU boards themselves provide converters to compensate... .which of course fucks everything up because the difference between the I/O levels is enough to draw current one way or the other and burn out components.
this is *EXACTLY* why the Certification Mark is so damn important, so as to be able to stomp from a Great Height on anyone not properly following the EOMA68 standard.
In any case, from what you've written, I guess we'll find out for ourselves soon enough about how successful the refinement process has been. Not that I think that it hasn't been successful enough, however.
[...]
Still, I wonder what those of us reading this list might be able to do to move the effort forward in our own way.
that would be great.
Any suggestions? :-)
a couple which were in my reply (two product ideas), whilst as you hint at most stuff now has to wait until i've got the prototypes for the jz4775 and a20 cpu cards and the two products microdesktop and laptop_15in done.
l.
arm-netbook@lists.phcomp.co.uk
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Alexander Stephen Thomas Ross -
Christopher Havel -
Hrvoje Lasic -
Luke Kenneth Casson Leighton -
Paul Boddie