http://rhombus-tech.net/community_ideas/mini_desktop/news/Revision_1_routing...
started this a week or so ago, it's been very rapid to complete because all the parts have been available from the other two products. it started as a copy of the flying squirrel; the audio section has been completely left as-is, and it turned rapidly into a desktop through the addition of the VGA and power circuits from the router.
so that's three major I/O board products in the pipeline. anyone got any suggestions on what to do next? laptop PCB? small robotics system?
l.
The laptop PCB is my first interest personally. It would be mostly similar to the flying squirrel and router as well, no?
I'd be glad to help, but I have no experience with PCB design. Very interested in seeing something specced out enough to work on bodies, though. Not sure how easy it would be, but I would definitely like to see constant placement of external connectors, screw holes, etc. so that the whole board could be swapped out in the future.
On Mon, Dec 2, 2013 at 8:37 PM, N Shipp nshp@mail4us.net wrote:
The laptop PCB is my first interest personally. It would be mostly similar to the flying squirrel and router as well, no?
mostly the flying squirrel. that PCB was designed *possibly* to be fitted to a 1024x768 LCD (it took placement of over 20 0R resistors to do that!). i'm thinking of a dual-LVDS screen, bigger power provision, battery etc. bunnie's schematics would probably help here although he's primarily focussed on US/EU component supply. the primary focus i have right now on component supply is Far East.
I'd be glad to help, but I have no experience with PCB design. Very interested in seeing something specced out enough to work on bodies, though.
great!
Not sure how easy it would be, but I would definitely like to see constant placement of external connectors, screw holes, etc. so that the whole board could be swapped out in the future.
not unreasonable, that... i hope!
l.
Sent from my iPhone
On Dec 2, 2013, at 2:20 PM, "luke.leighton" luke.leighton@gmail.com wrote:
http://rhombus-tech.net/community_ideas/mini_desktop/news/Revision_1_routing...
started this a week or so ago, it's been very rapid to complete because all the parts have been available from the other two products. it started as a copy of the flying squirrel; the audio section has been completely left as-is, and it turned rapidly into a desktop through the addition of the VGA and power circuits from the router.
so that's three major I/O board products in the pipeline. anyone got any suggestions on what to do next? laptop PCB? small robotics system?
Waiting on coordination of other parties before officially announcing, but my company is almost done with the mechanical keyboard thin client, and we've got preliminary drawings completed of the advanced engineering board/carrier board(it would qualify as a small robotics platform). And we've started a collaboration testing the idea of retrofitting an IBM Thinkpad with a custom EOMA PCB/Motherboard (the FST was a great inspiration.)
-C
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 Mon, Dec 2, 2013 at 8:55 PM, Christopher Thomas christopher@firemothindustries.com wrote:
Sent from my iPhone
On Dec 2, 2013, at 2:20 PM, "luke.leighton" luke.leighton@gmail.com wrote:
http://rhombus-tech.net/community_ideas/mini_desktop/news/Revision_1_routing...
started this a week or so ago, it's been very rapid to complete because all the parts have been available from the other two products. it started as a copy of the flying squirrel; the audio section has been completely left as-is, and it turned rapidly into a desktop through the addition of the VGA and power circuits from the router.
so that's three major I/O board products in the pipeline. anyone got any suggestions on what to do next? laptop PCB? small robotics system?
Waiting on coordination of other parties before officially announcing, but my company is almost done with the mechanical keyboard thin client,
oh that's really good to hear.
and we've got preliminary drawings completed of the advanced engineering board/carrier board(it would qualify as a small robotics platform).
awesome! i really want something like that for my daughter. to make some sort of colour-sensing robot with a webcam, do something similar to adamgreig's followingrobot (it tracks "anything that's red") but perhaps a little more sophisticated.
And we've started a collaboration testing the idea of retrofitting an IBM Thinkpad with a custom EOMA PCB/Motherboard (the FST was a great inspiration.)
ooo fiiinally.
l.
On Mon, 2013-12-02 at 20:20 +0000, luke.leighton wrote:
http://rhombus-tech.net/community_ideas/mini_desktop/news/Revision_1_routing...
started this a week or so ago, it's been very rapid to complete because all the parts have been available from the other two products. it started as a copy of the flying squirrel; the audio section has been completely left as-is, and it turned rapidly into a desktop through the addition of the VGA and power circuits from the router.
so that's three major I/O board products in the pipeline. anyone got any suggestions on what to do next? laptop PCB? small robotics system?
Want these robots? :)
I'd love to release these robots as 100% gpl'd items: http://www.youtube.com/watch?v=RuhuGvgm_FE http://www.youtube.com/watch?v=6THIO6KVLfU
(And also some time in the future, a 100% gpl'd parametric gambas program to generate robot parts. It reads a in a spreadsheet filled with names of parts such as arm length, body width, head size and so on, fitting angle of the limbs and their dimensions and so on, and all the parts are then generated for laser cutting on the fly. A lot of it got done, but the maths got a bit complex. The software hadn't been thought through with the matrix maths in place - so a large part of it needs to be scrubbed and started again.)
Time to face a little reality though in increasing severity:
1. You need the internal 3.3V line brought out from EOMA68 to one of the pins for general circuit design reasons.
2. Not sure about the USD75. Is it going to get cheaper any time soon?
3. At the moment there is no way to cooperate with everyone using closed sources PCB packages and the list of hardware mistakes are piling up as cost somewhere. This is driving a wedge through all things good and possible. I only want to work in open sourced KiCAD. The limitations are not significant to getting the real work done and avoiding undesirable future costs. In the long run its better as more engineers can help. So despite your whining, I think its time to quit whining, absorb the pain, and you + stragglers got on to KiCAD. We can all move forward a lot quicker if we are all on the same page.
On Tue, Dec 3, 2013 at 10:00 AM, joem joem@martindale-electric.co.uk wrote:
- You need the internal 3.3V line brought out from EOMA68 to one of the
pins for general circuit design reasons.
not going to happen. sorry. designs need to take that into account. apart from anything there will be boards in the future that don't *have* a 3.3V line (for whatever reason).
so not only was the time to say these things about 18 months ago but the answer would still have been no.
- Not sure about the USD75. Is it going to get cheaper any time soon?
in quantity 10k and above, probably yes. because they will be designed differently. and be a different product entirely. so... no.
plus remember that $75 is for *two* boards, and tax, and shipping, and testing, and packaging, and profit (a small one) and everything else.
strictly speaking the sale price should be double what it is.
- At the moment there is no way to cooperate with everyone using closed sources PCB packages and the list of hardware mistakes are piling up as cost somewhere. This is driving a wedge through all things good and possible. I only want to work in open sourced KiCAD. The limitations are not significant
they are a complete show-stopper for someone with my limited available time, lack of knowledge and insufficient expertise. simple as that.
to getting the real work done and avoiding undesirable future costs.
then i need people to take over designing these I/O Board PCBs.
as long as i am continuing to work without any visible day-to-day assistance i will continue to use the software that i have the capability to use and have confidence in.
l.
On Tue, 2013-12-03 at 11:35 +0000, luke.leighton wrote:
On Tue, Dec 3, 2013 at 10:00 AM, joem joem@martindale-electric.co.uk wrote:
- You need the internal 3.3V line brought out from EOMA68 to one of the
pins for general circuit design reasons.
not going to happen. sorry. designs need to take that into account. apart from anything there will be boards in the future that don't *have* a 3.3V line (for whatever reason).
Not a request. The 3.3V line is the pull up line for GPIO lines. Something to get right in next revision.
- Not sure about the USD75. Is it going to get cheaper any time soon?
in quantity 10k and above, probably yes. because they will be designed differently. and be a different product entirely. so... no.
plus remember that $75 is for *two* boards, and tax, and shipping, and testing, and packaging, and profit (a small one) and everything else.
Its $75 for CPU board and meb + shipping + taxes.
- At the moment there is no way to cooperate with everyone using closed sources PCB packages and the list of hardware mistakes are piling up as cost somewhere. This is driving a wedge through all things good and possible. I only want to work in open sourced KiCAD. The limitations are not significant
they are a complete show-stopper for someone with my limited available time, lack of knowledge and insufficient expertise. simple as that.
KiCAD web site has added a lot more video tutorials recently. Watch it 10 times and follow blindly until it ground in. I can also help make the 3D parts and answer a lot of questions until its all up to speed for anyone wanting to do all this. Searching the kicad mailing list also answers many a question.
to getting the real work done and avoiding undesirable future costs.
then i need people to take over designing these I/O Board PCBs.
The main 'problem' with kicad is that it is too fast once you know how to work it. Unlike the commercial packages, all the data is stored in text files. Simple diff after a modification will show which parameters get modified when a small change is made. A lot of the difficult work can be done with text editors, spreadsheets, and copy/paste which speeds up the work enormously. You end up with dozens of boards ready to go and not enough time to test.
as long as i am continuing to work without any visible day-to-day assistance i will continue to use the software that i have the capability to use and have confidence in.
Board design has to be done in small incremental steps. Just like unix philosophy, build it small and efficient and make sure it works 100% and fully debugged before moving on to the bigger things. So the real work is to produce an axp power supply module, an ethernet module, a DDR + CPU module, audio module, flash module, lcd module, hdmi module, vga module, etc and making sure each bit works 100% and then adding them together to make final product. The modules cost less and easier to fund. Once modules are working, you never look back and race to build bigger and bigger projects at a faster rate than anyone else can match.
Monolithic designs are great if you have resources to make additional revisions and to pound each variant with enough resources until it works.
On Wed, Dec 4, 2013 at 9:14 AM, joem joem@martindale-electric.co.uk wrote:
On Tue, 2013-12-03 at 11:35 +0000, luke.leighton wrote:
On Tue, Dec 3, 2013 at 10:00 AM, joem joem@martindale-electric.co.uk wrote:
- You need the internal 3.3V line brought out from EOMA68 to one of the
pins for general circuit design reasons.
not going to happen. sorry. designs need to take that into account. apart from anything there will be boards in the future that don't *have* a 3.3V line (for whatever reason).
Not a request. The 3.3V line is the pull up line for GPIO lines. Something to get right in next revision.
joe: it's still not going to happen. there are not enough pins. I/O board designs will need to generate the correct 3.3v compatible TTL levels by having the correct regulators on the I/O board. as 3.3v TTL levels are the same everywhere this is perfectly feasible.
there is therefore not only enough pins available, but also this is a non-issue.
also there is the issue of backwards-compatibility if there are revisions. any further revisions require complexity to be introduced into future revisions of both CPU Cards *and* I/O boards. that is not going to happen.
therefore please accept that i have carefully considered what you have said and the answer is no.
- Not sure about the USD75. Is it going to get cheaper any time soon?
in quantity 10k and above, probably yes. because they will be designed differently. and be a different product entirely. so... no.
plus remember that $75 is for *two* boards, and tax, and shipping, and testing, and packaging, and profit (a small one) and everything else.
Its $75 for CPU board and meb + shipping + taxes.
yes. QiMod Ltd is acting as the distributor, not the end-user supplier. the choice of price for the pair of boards, being supplied by a 3rd party, is completely outside of QiMod Ltd's control.
- At the moment there is no way to cooperate with everyone using closed sources PCB packages and the list of hardware mistakes are piling up as cost somewhere. This is driving a wedge through all things good and possible. I only want to work in open sourced KiCAD. The limitations are not significant
they are a complete show-stopper for someone with my limited available time, lack of knowledge and insufficient expertise. simple as that.
KiCAD web site has added a lot more video tutorials recently.
the tutorials are not relevant, here. joe: i've been working with KiCAD for around 4 to 5 years. i am familiar with it. compared to PADS it has completely inadequate functionality and design rule safety checks.
regarding the speed at which designs can be created: that is completely irrelevant if i am creating completely wrong designs, isn't it?
so until someone takes over designs who has the required knowledge and expertise, i have to stick with "safe" software packages.
l.
On Wed, 2013-12-04 at 12:22 +0000, luke.leighton wrote:
On Wed, Dec 4, 2013 at 9:14 AM, joem joem@martindale-electric.co.uk wrote:
On Tue, 2013-12-03 at 11:35 +0000, luke.leighton wrote:
On Tue, Dec 3, 2013 at 10:00 AM, joem joem@martindale-electric.co.uk wrote:
- You need the internal 3.3V line brought out from EOMA68 to one of the
pins for general circuit design reasons.
not going to happen. sorry. designs need to take that into account. apart from anything there will be boards in the future that don't *have* a 3.3V line (for whatever reason).
Not a request. The 3.3V line is the pull up line for GPIO lines. Something to get right in next revision.
joe: it's still not going to happen. there are not enough pins. I/O board designs will need to generate the correct 3.3v compatible TTL levels by having the correct regulators on the I/O board. as 3.3v TTL levels are the same everywhere this is perfectly feasible.
Hmm... some misunderstanding going on here. The "pull up line for GPIO" != any old power supply line of same voltage.
It depends on circuit design. If it were a TTL board, or something like a PIC running on 5V, then the 5V line will have become the GPIO pull up line. It just so happens that for the GPIO in the EOMA, the pull up line for GPIO is specifically the 3.3V line powering the GPIO.
(For ARM chips, the GPIO lines can usually be powered by a separate independent power supply to save power. So it can be set to 2.5V for example which will work so long as the circuits that it is interfacing to is designed to work with those levels.)
there is therefore not only enough pins available, but also this is a non-issue.
May be use up one more of the GND pins?
also there is the issue of backwards-compatibility if there are revisions. any further revisions require complexity to be introduced into future revisions of both CPU Cards *and* I/O boards. that is not going to happen.
therefore please accept that i have carefully considered what you have said and the answer is no.
- Not sure about the USD75. Is it going to get cheaper any time soon?
in quantity 10k and above, probably yes. because they will be designed differently. and be a different product entirely. so... no.
plus remember that $75 is for *two* boards, and tax, and shipping, and testing, and packaging, and profit (a small one) and everything else.
Its $75 for CPU board and meb + shipping + taxes.
yes. QiMod Ltd is acting as the distributor, not the end-user supplier. the choice of price for the pair of boards, being supplied by a 3rd party, is completely outside of QiMod Ltd's control.
I plan to buy a couple when they become generally available. I got 50 x 5" 800x480 screens to play with at the moment :) The price of these boards are coming down so fast its possible to build desktop computing clusters. I worked out a proper 3D stackable case design for that and ordered 6 x cubies a few days back. Easily modified to fit the eoma which is better suited for cluster building because a large part of the CPU board is not exposed to the elements. So despite the slight premium compared to similar spec boards, the main board not being exposed to the elements will still make it a winner for cluster computing.
- At the moment there is no way to cooperate with everyone using closed sources PCB packages and the list of hardware mistakes are piling up as cost somewhere. This is driving a wedge through all things good and possible. I only want to work in open sourced KiCAD. The limitations are not significant
they are a complete show-stopper for someone with my limited available time, lack of knowledge and insufficient expertise. simple as that.
KiCAD web site has added a lot more video tutorials recently.
the tutorials are not relevant, here. joe: i've been working with KiCAD for around 4 to 5 years. i am familiar with it. compared to PADS it has completely inadequate functionality and design rule safety checks.
regarding the speed at which designs can be created: that is completely irrelevant if i am creating completely wrong designs, isn't it?
so until someone takes over designs who has the required knowledge and expertise, i have to stick with "safe" software packages.
Weelllllll!
The stuff I get done takes hours to days and nearly everything I build works first time. So lead by example I guess!!!!!!
When I get time, I break down Dr. Ajiths design into pre-routed modules so it takes next to no time to glue together to make into larger modules. Stuff that must be done in PADS can be exported as Gerbers, KiCAD can import gerbers, so you could route the DDR and CPU in PADs, export the gerber, pull Gerber into KiCAD and do the non-critical stuff there by pulling in the various modules as needed.
Any way its up to you. Speed up the work using well built and tried and tested modules that everyone has shared, tried and tested, or go the monolithic way. Less chance of donating help if doing monolithic designs and going the PADs way or any other proprietary package. But so long as it works, who cares? :)
On Wed, Dec 4, 2013 at 2:42 PM, joem joem@martindale-electric.co.uk wrote:
On Wed, 2013-12-04 at 12:22 +0000, luke.leighton wrote:
On Wed, Dec 4, 2013 at 9:14 AM, joem joem@martindale-electric.co.uk wrote:
On Tue, 2013-12-03 at 11:35 +0000, luke.leighton wrote:
On Tue, Dec 3, 2013 at 10:00 AM, joem joem@martindale-electric.co.uk wrote:
- You need the internal 3.3V line brought out from EOMA68 to one of the
pins for general circuit design reasons.
not going to happen. sorry. designs need to take that into account. apart from anything there will be boards in the future that don't *have* a 3.3V line (for whatever reason).
Not a request. The 3.3V line is the pull up line for GPIO lines. Something to get right in next revision.
joe: it's still not going to happen. there are not enough pins. I/O board designs will need to generate the correct 3.3v compatible TTL levels by having the correct regulators on the I/O board. as 3.3v TTL levels are the same everywhere this is perfectly feasible.
Hmm... some misunderstanding going on here. The "pull up line for GPIO" != any old power supply line of same voltage.
the specification for all TTL signals is "that of the Allwinner A20". that means 3.3v TTL for GPIO. that's the end of it.
It depends on circuit design.
no, it depends on the specification. and the specification is "3.3v TTL for all GPIO".
in case that is not clear, that is "high" voltage of 2.0 volts, threshold of 1.4 V and "low" voltage of 0.8 V.
is that clear?
if it is not clear, what is not clear about the "high" threshold voltage being 2.0 v and "low" being below 0.8V?
in case it is still not clear, at what point is a voltage of exactly 3.3v required in order to set a TTL "high" signal of over 2.0v?
If it were a TTL board, or something like a PIC running on 5V, then the 5V line will have become the GPIO pull up line. It just so happens that for the GPIO in the EOMA, the pull up line for GPIO is specifically the 3.3V line powering the GPIO.
no, it is not. the voltages are "2.0v" for HIGH and "0.8v" for LOW". what about this is not clear?>
there is therefore not only enough pins available, but also this is a non-issue.
May be use up one more of the GND pins?
perhaps it was not clear enough, joe. which bit of "this results in design complexity and additional cost, both of which are unacceptable" was not clear?
i apologise but i'm having real difficulty understanding why you're not following the logical reasoning and decision-making that i'm presenting to you.
I plan to buy a couple when they become generally available. I got 50 x 5" 800x480 screens to play with at the moment :) The price of these boards are coming down so fast its possible to build desktop computing clusters. I worked out a proper 3D stackable case design for that and ordered 6 x cubies a few days back. Easily modified to fit the eoma which is better suited for cluster building because a large part of the CPU board is not exposed to the elements. So despite the slight premium compared to similar spec boards, the main board not being exposed to the elements will still make it a winner for cluster computing.
indeed. once we have some sales going we can look at quad-core SoCs again, as well as a GbE and RAM upgrade to the EOMA68-A20.
so until someone takes over designs who has the required knowledge and expertise, i have to stick with "safe" software packages.
Weelllllll!
yes :)
The stuff I get done takes hours to days and nearly everything I build works first time. So lead by example I guess!!!!!!
you have expertise that i don't have, basically! i've only been working (full-ish-time) with board designs for about a year, working with other experts who do have the expertise and knowledge. you've got... what... NN years experience? that's the difference.
When I get time, I break down Dr. Ajiths design into pre-routed modules so it takes next to no time to glue together to make into larger modules. Stuff that must be done in PADS can be exported as Gerbers, KiCAD can import gerbers, so you could route the DDR and CPU in PADs, export the gerber, pull Gerber into KiCAD and do the non-critical stuff there by pulling in the various modules as needed.
Any way its up to you. Speed up the work using well built and tried and tested modules that everyone has shared, tried and tested, or go the monolithic way. Less chance of donating help if doing monolithic designs and going the PADs way or any other proprietary package.
well, the preliminary schematics designs i've done are still in http://git.rhombus-tech.net/eoma.git - anyone is welcome to improve and continue those GPLv3+ designs.
l.
in case that is not clear, that is "high" voltage of 2.0 volts, threshold of 1.4 V and "low" voltage of 0.8 V.
is that clear?
Still feeding the confusion.
A pull up point and pull down point has nothing to do with voltages.
e.g. if you remember HNO's fix for RS232 problem. It requires connection to the pull up point. It was labelled as the 3.3V line - with the implicit meaning that it was the pull up point that all EEs would know about. (All EEs would also implicitly know that connecting to a substitute arbitrary 3.3V point is utterly meaningless.)
So, without a pull up point for GPIO lines, certain types of electrical and electronic problems cannot easily be solved.
Instead of calling it 3.3V line, you could call it GPIO_PULL_UP line and then no one has to know what voltage its running at, and implicitly also beneficially assume they cannot draw power from that line, or rely on it being 3.3V in the future.
On Thu, Dec 5, 2013 at 9:22 AM, joem joem@martindale-electric.co.uk wrote:
in case that is not clear, that is "high" voltage of 2.0 volts, threshold of 1.4 V and "low" voltage of 0.8 V.
is that clear?
Still feeding the confusion.
well, regardless, it's too late. there will be no further changes (except one, related to adding a reset line, and that's more than i'm comfortable with).
e.g. if you remember HNO's fix for RS232 problem.
... and it was fixed. no 3.3v line required.
It requires connection to the pull up point.
no it does not. the diode does the job.
It was labelled as the 3.3V line - with the implicit meaning that it was the pull up point that all EEs would know about. (All EEs would also implicitly know that connecting to a substitute arbitrary 3.3V point is utterly meaningless.)
a 3.3v point is not necessary.
So, without a pull up point for GPIO lines,
which will not be provided.
certain types of electrical and electronic problems cannot easily be solved.
tough. they can be solved. "ease" has nothing to do with it. it's too late.
Instead of calling it 3.3V line, you could call it GPIO_PULL_UP line
the answer's no. it's too late. this should have been raised 18-24 months ago.
there will be no changes.
sorry.
l.
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