http://rhombus-tech.net/community_ideas/micro_desktop/news/
as promised the micro desktop is being developed, news and features on the page.
l.
On Thu, May 29, 2014 at 12:33 PM, Luke Kenneth Casson Leighton < lkcl@lkcl.net> wrote:
http://rhombus-tech.net/community_ideas/micro_desktop/news/
as promised the micro desktop is being developed, news and features on the page.
l.
What voltage is the power input? 5v DC I assume? Be aware that 5v power supplies on eg eBay (when the customer wants to replace things later on) can come with either 5.5*2.1mm or 5.5*2.5mm plugs. A 5.5*2.5mm plug in that socket will physically fit, but it will heat up and burn out the jack -- and the less-than-ideal connection will inevitably screw things up in other ways as well...
I can think of two ways to fix this. One is to make it a 5.5*2.5mm jack (this is probably simplest, easiest, and best). The other is to label it clearly on both PCB and outer enclosure. If the second idea (labeling) is chosen, then it becomes (logically) necessary somehow to find some means of convincing the consumer/customer never to put a 2.5mm ID plug in that jack, which is a very difficult task. I've got decent eyes and *I* can't see the difference, and a lot of people in the US (especially in the region where I live) seem to be very good at ignoring warning labels and, consequentially, doing very stupid things that break everything (whereupon they complain, usually through the courts, that it wasn't labeled adequately).
There is an added bonus to making the jack 2.5mm ID -- most 12v power supplies with barrel jacks are 2.1mm ID -- meaning that if a consumer is totally clueless about voltages and how not to fry a computer by severely overvolting it, they will be largely unsuccessful in replacing the 5v wart with a 12v wart... it just won't fit.
You really do want to be thinking of the "Doug Hefernan" type here. (That was the name of the character portrayed by Kevin James on a sitcom called "The King of Queens". I can easily picture him saying "oh shut up all of these adapters are the same" and plugging in the wrong one to the tune of a dramatic shower of sparks... there are a LOT of people Stateside who are like that, sadly.)
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thanks super human luke ;) .
what about a flexible power suppy with wide voltage ranges? 3V(?) to 13V. so it can be connect to a car/12v batt and a built in Li-* battery charger/monitor? I guess this would mean needing to use the ardunio-like chip for the power status info? so not so easy then. well there's microups https://www.indiegogo.com/projects/microups-for-raspberry-beaglebone-cubiebo...
while it looks like It's not so suitable for my diy handheld computer project with it having vga instead of plain RGB/TTL. I'll order one anyway, I'll find a use for it :)
On Thu, May 29, 2014 at 6:59 PM, Alexander Stephen Thomas Ross maillist_arm-netbook@aross.me wrote:
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thanks super human luke ;) .
what about a flexible power suppy with wide voltage ranges?
done already - not 3V, but 4.5V
while it looks like It's not so suitable for my diy handheld computer project with it having vga instead of plain RGB/TTL. I'll order one anyway, I'll find a use for it :)
you got a MEBv1 already, right?
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On 29/05/14 20:56, Luke Kenneth Casson Leighton wrote:
On Thu, May 29, 2014 at 6:59 PM, Alexander Stephen Thomas Ross maillist_arm-netbook@aross.me wrote: thanks super human luke ;) .
what about a flexible power suppy with wide voltage ranges?
done already - not 3V, but 4.5V
ok, 3v (rounded to the nearest hole num.) was only cus I was thinking about Li-* batterys which and 3.3~v.
while it looks like It's not so suitable for my diy handheld computer project with it having vga instead of plain RGB/TTL. I'll order one anyway, I'll find a use for it :)
you got a MEBv1 already, right?
MEB?
oh... Don't think that I can design one. that's beyond me. I was just going to stick some bits together which is about my level. sorry if I hadn’t communicated this and got peoples hopes up. It's going to be a bulky pocket computer for large pockets hehe. I don't know how hard it would be to learn how to do it but I just can't spend the time it would need on it. nor would I have a few hundred £ to get it made up. Better off becoming a £100,000aire by shifting my butt and getting some work done on non-existing biz X. :) then I would have funds to donate :D. ok I'm dreaming but thats my goal (make money to fund projects I like and other non-£ goals).
On Thu, May 29, 2014 at 10:07 PM, Alexander Stephen Thomas Ross maillist_arm-netbook@aross.me wrote:
you got a MEBv1 already, right?
MEB?
oh... Don't think that I can design one.
it's already done alex.
On Thu, May 29, 2014 at 5:55 PM, Christopher Havel laserhawk64@gmail.com wrote:
On Thu, May 29, 2014 at 12:33 PM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
http://rhombus-tech.net/community_ideas/micro_desktop/news/
as promised the micro desktop is being developed, news and features on the page.
l.
What voltage is the power input?
it iiiis aaaaaa.... RT8288A so that's a buck converter, input anywhere between 4.5V and 26V, and it's tuned with 2 resistors to create 5.0v. it's about 75% efficient or so according to the datasheet.
so luckily, 5V or 12V input PSU it really won't care. the caution about the 2 different plugs appreciated, but i have already done the part and i know it takes time to redo them and find suitable replacements and the suppliers and so on, and i'm not hugely keen on going through that again right now.
i think a good voltage range is enough to be getting on with: the PSU only needs to be 10W so i think we're good.
l.
On 29/05/14 21:55, Luke Kenneth Casson Leighton wrote:
so luckily, 5V or 12V input PSU it really won't care. the caution about the 2 different plugs appreciated, but i have already done the part and i know it takes time to redo them and find suitable replacements and the suppliers and so on, and i'm not hugely keen on going through that again right now.
I think for a first, demonstration product we can expect buyers to use a power supply with the correct specifications. There'll be plenty of time to refine and idiot-proof the design before mass production starts...
Quick, cheap, easy are definitely the priorities at the moment.
BOM and schematic PDF are here, review appreciated. i have to fix up the EOMA68-A20 revise it to remove SATA, add 2nd USB etc. before completing this board but we have enough to be getting on with for pricing from the BOM.
l.
Just so I'm aware -- I know I can't afford it; I wish I could so much that it almost physically hurts -- about how much would it be for a revised A20 card and a mini desktop setup, before shipping?
On Thu, May 29, 2014 at 4:43 PM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
BOM and schematic PDF are here, review appreciated. i have to fix up the EOMA68-A20 revise it to remove SATA, add 2nd USB etc. before completing this board but we have enough to be getting on with for pricing from the BOM.
l.
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On Thu, May 29, 2014 at 9:47 PM, Christopher Havel laserhawk64@gmail.com wrote:
Just so I'm aware -- I know I can't afford it; I wish I could so much that it almost physically hurts -- about how much would it be for a revised A20 card and a mini desktop setup, before shipping?
it entirely depends on quantity ordered. 25 would be around the $160 mark including shipping, 100 probably around the $120 and 500 probably around the $100 mark. by the time you get to 2500 that's when it can be around $75.
l.
I'd only need one... I'm one lonely hobbyist... I'd get two but Mom is a Windows lover.
On Thu, May 29, 2014 at 5:20 PM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
On Thu, May 29, 2014 at 9:47 PM, Christopher Havel laserhawk64@gmail.com wrote:
Just so I'm aware -- I know I can't afford it; I wish I could so much
that
it almost physically hurts -- about how much would it be for a revised
A20
card and a mini desktop setup, before shipping?
it entirely depends on quantity ordered. 25 would be around the $160 mark including shipping, 100 probably around the $120 and 500 probably around the $100 mark. by the time you get to 2500 that's when it can be around $75.
l.
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On Thu, May 29, 2014 at 10:22 PM, Christopher Havel laserhawk64@gmail.com wrote:
I'd only need one... I'm one lonely hobbyist... I'd get two but Mom is a Windows lover.
ooo, steadyyy :)
so. you're one. so now we need 24, or 99, or 499, or 2499 :)
On Thu, May 29, 2014 at 5:29 PM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
so. you're one. so now we need 24, or 99, or 499, or 2499 :)
I'm one if I can pay for it when the time comes. That's always a very large question mark...
I have almost exactly $2k per month for two people. Here in my little North Carolina town, that's just barely enough for bills and food... we rarely have anything left over at the end of the month, and often we're in the red.
On Thu, May 29, 2014 at 10:33 PM, Christopher Havel laserhawk64@gmail.com wrote:
On Thu, May 29, 2014 at 5:29 PM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
so. you're one. so now we need 24, or 99, or 499, or 2499 :)
I'm one if I can pay for it when the time comes. That's always a very large question mark...
I have almost exactly $2k per month for two people. Here in my little North Carolina town, that's just barely enough for bills and food... we rarely have anything left over at the end of the month, and often we're in the red.
ok, so tell me - i take it you have time on your hands: what can you do for this project that's worth the cost of one of these micro-desktop boards and a CPU Card?
l.
On Thu, May 29, 2014 at 5:38 PM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
ok, so tell me - i take it you have time on your hands: what can you do for this project that's worth the cost of one of these micro-desktop boards and a CPU Card?
I'll be honest: I have no idea. I did put up that R-2R ladder thing, but that's about the extent of what I can do with electronics right now. I'm a real noob there. Programming for me is limited to QuickBASIC (specifically MS QuickBASIC PDS 7.1 or /very/ similar). I've tried three times to learn C++ and it went rather poorly (I'm being kind) all three times. Needless to say, that's basically useless as well unless you want to run FreeDOS on these cards for something (I don't think so!). I could probably port over to QB64 if I wanted to muck with that, but it'd be a real PITA for not much gain.
I'm something of an artist, but I'm much better with pencil/pen and paper than with computer graphics so I probably can't even do advertising stuff. Right now I don't even have computer graphics capability -- a couple months ago I moved to Linux full time, and I need to install WINE to get my software (CorelDRAW X3, a gift from my father) to run in Puppy (my distro of choice) -- and I have not installed WINE yet. (Once I do, making CorelDRAW actually work will take some finagling.) I took a drafting course in high school (ten years ago) and somewhere I have a book (if I haven't gotten rid of it) on drafting, but I'm allergic to using multiple pencils (meaning all lines are the same width) and I have a hard time with rulers (they move on me, lol!). I'm also not that hot at thinking in 3D... I'm positively pathetic at shading (when I'm not doing drafting) and I simply cannot wrap my head around eg 3D modeling (I tried Sketchup... Sketchup and I sort of came to a mutual understanding that things were not going to work out, and we parted ways). I can do orthos, and I can usually avoid designing something that's too Escher-esque to work in Euclidean space, but I do have my moments. Also I'm totally worthless drawing organic figures. Flowers and people are very hard for me to draw for some reason...
*phew* that ended up being a little longer than I thought it would. Hopefully there's something in there that's useful.
On Thu, May 29, 2014 at 10:52 PM, Christopher Havel laserhawk64@gmail.com wrote:
On Thu, May 29, 2014 at 5:38 PM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
ok, so tell me - i take it you have time on your hands: what can you do for this project that's worth the cost of one of these micro-desktop boards and a CPU Card?
I'll be honest: I have no idea.
ok, i got one - how about putting on the eoma discussion page the stuff that was talked about a few days ago? just cut/paste and then perhaps research some of the arduino material.
l.
On Fri, May 30, 2014 at 4:16 AM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
ok, i got one - how about putting on the eoma discussion page the stuff that was talked about a few days ago? just cut/paste and then perhaps research some of the arduino material.
Just looked back at this -- I honestly thought it was someone else who posted it and was going to ask your opinion, LOL. I can definitely do copypasta from thread to discussion page, although if it uses neither HTML nor BBCode for formatting I'll have issues. I'll be starting tomorrow at the earliest, since it's getting late here now -- what specific threads/content were you thinking of, so I don't mess up? (I have a very short memory, and I'm easily confused -- sorry!)
Also: I know very little about Arduino -- except that it's programmed primarily in a language I don't speak ;) I'll have to conquer that, eventually, for a project of my own... but for now that is not to be. I've done a little work with PICAXE but they won't work here -- no derivative works for them, *and* they're closed-source. I know someone who is very heavily into Arduino stuff, but I've gotten the impression from what he's told me in the past, that he'd probably not want to be roped into contributing to EOMA. He's trying to forget his past forays into electronics and computers so that he can focus as exclusively as possible on Arduino stuff... I can sort of understand and respect that. He's been doing that stuff for a very long time, is my understanding, so he probably is just clearing space so new knowledge can be stored :P
I do have some obligation to him, though, to expand my electronic knowledge -- after all, he did give me a 70s vintage Tektronix 422 recently ;) I've no idea how to use it yet -- I need to get on that, soon. (He gave me the manual with the scope...) Maybe once I get the hang of that, I can contribute more... I dunno. I've also seen, on Hackaday, a very simple device that would permit me to run that o-scope as an 8-channel logic analyzer, although it would pale in comparison to the real thing... IIRC, it's basically a shift-register setup. I have the Hackaday blurb bookmarked, if people are interested.
For now, it's late, and I'm going to wander off towards my bed.
On Sat, May 31, 2014 at 4:32 AM, Christopher Havel laserhawk64@gmail.com wrote:
On Fri, May 30, 2014 at 4:16 AM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
ok, i got one - how about putting on the eoma discussion page the stuff that was talked about a few days ago? just cut/paste and then perhaps research some of the arduino material.
Just looked back at this -- I honestly thought it was someone else who posted it and was going to ask your opinion, LOL. I can definitely do copypasta from thread to discussion page, although if it uses neither HTML nor BBCode for formatting I'll have issues. I'll be starting tomorrow at the earliest, since it's getting late here now -- what specific threads/content were you thinking of, so I don't mess up? (I have a very short memory, and I'm easily confused -- sorry!)
foundation, standards implementation, purpose of trademark protection.
Luke -- I put in some stuff on the Rhombus-Tech discussion page.
It shows up at http://rhombus-tech.net/index/discussion/?updated ...but it's not showing at http://rhombus-tech.net/index/discussion http://rhombus-tech.net/index/discussion/?updated
Any reason for that? How do I fix that, or is that someone else's job? Also, I know that's not all of what you wanted in there, but let me know what you think of what's there now and I can add more once you tell me what you think.
On Sat, May 31, 2014 at 3:38 AM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
On Sat, May 31, 2014 at 4:32 AM, Christopher Havel laserhawk64@gmail.com wrote:
On Fri, May 30, 2014 at 4:16 AM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
ok, i got one - how about putting on the eoma discussion page the stuff that was talked about a few days ago? just cut/paste and then perhaps research some of the arduino material.
Just looked back at this -- I honestly thought it was someone else who posted it and was going to ask your opinion, LOL. I can definitely do copypasta from thread to discussion page, although if it uses neither
HTML
nor BBCode for formatting I'll have issues. I'll be starting tomorrow at
the
earliest, since it's getting late here now -- what specific
threads/content
were you thinking of, so I don't mess up? (I have a very short memory,
and
I'm easily confused -- sorry!)
foundation, standards implementation, purpose of trademark protection.
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 Sat, May 31, 2014 at 4:06 PM, Christopher Havel laserhawk64@gmail.com wrote:
Luke -- I put in some stuff on the Rhombus-Tech discussion page.
It shows up at http://rhombus-tech.net/index/discussion/?updated ...but it's not showing at http://rhombus-tech.net/index/discussion
index is an HTML page (not mdwn) so it won't - that's ok.
Any reason for that? How do I fix that, or is that someone else's job? Also, I know that's not all of what you wanted in there, but let me know what you think of what's there now and I can add more once you tell me what you think.
looks great. would you like to follow some of the leads recommended (arduino ones) and see what they do, cut/paste into that page, then we can evaluate them?
l.
On Sat, May 31, 2014 at 3:38 AM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
On Sat, May 31, 2014 at 4:32 AM, Christopher Havel laserhawk64@gmail.com wrote:
On Fri, May 30, 2014 at 4:16 AM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
ok, i got one - how about putting on the eoma discussion page the stuff that was talked about a few days ago? just cut/paste and then perhaps research some of the arduino material.
Just looked back at this -- I honestly thought it was someone else who posted it and was going to ask your opinion, LOL. I can definitely do copypasta from thread to discussion page, although if it uses neither HTML nor BBCode for formatting I'll have issues. I'll be starting tomorrow at the earliest, since it's getting late here now -- what specific threads/content were you thinking of, so I don't mess up? (I have a very short memory, and I'm easily confused -- sorry!)
foundation, standards implementation, purpose of trademark protection.
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
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On Sat, May 31, 2014 at 2:42 PM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
looks great. would you like to follow some of the leads recommended (arduino ones) and see what they do, cut/paste into that page, then we can evaluate them?
I guess... I don't really have a clear picture tho of what you're looking for (my fault -- I *did* say I was clueless!)...
On Sat, May 31, 2014 at 7:45 PM, Christopher Havel laserhawk64@gmail.com wrote:
On Sat, May 31, 2014 at 2:42 PM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
looks great. would you like to follow some of the leads recommended (arduino ones) and see what they do, cut/paste into that page, then we can evaluate them?
I guess... I don't really have a clear picture tho of what you're looking for (my fault -- I *did* say I was clueless!)...
basically i would like a summary of what the arduino company is allowing 3rd parties to do, and under what conditions. i'd like to see a summary of what is on the links that someone posted (and you cut/paste onto the discussion page).
l.
On Sat, May 31, 2014 at 5:18 PM, Luke Kenneth Casson Leighton <lkcl@lkcl.net
wrote:
basically i would like a summary of what the arduino company is allowing 3rd parties to do, and under what conditions. i'd like to see a summary of what is on the links that someone posted (and you cut/paste onto the discussion page).
I can do that! It'll be a couple hours tho -- I'm workin on somethin :P
On Sat, May 31, 2014 at 10:19 PM, Christopher Havel laserhawk64@gmail.com wrote:
On Sat, May 31, 2014 at 5:18 PM, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
basically i would like a summary of what the arduino company is allowing 3rd parties to do, and under what conditions. i'd like to see a summary of what is on the links that someone posted (and you cut/paste onto the discussion page).
I can do that! It'll be a couple hours tho -- I'm workin on somethin :P
no rush.
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On Thursday 29 May 2014 22:20:39 Luke Kenneth Casson Leighton wrote:
25 [ revised A20 card and mini desktop setup ] would be around the $160 mark including shipping,
I would take one at that price
100 probably around the $120
Or 2 at that price.
All the best
On Thu, 29 May 2014, Luke Kenneth Casson Leighton wrote:
BOM and schematic PDF are here, review appreciated.
I can get the BOM, but not the PDF :
Forbidden You don't have permission to access /~lkcl/eoma/microdesktop/microdesktop.pdf on this server.
Goodbye, Stéphane.
On Thu, May 29, 2014 at 11:20 PM, Stéphane Goujet stephane.goujet@wanadoo.fr wrote:
On Thu, 29 May 2014, Luke Kenneth Casson Leighton wrote:
BOM and schematic PDF are here, review appreciated.
I can get the BOM, but not the PDF :
Forbidden You don't have permission to access /~lkcl/eoma/microdesktop/microdesktop.pdf on this server.
sorted.
Goodbye, Stéphane.
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On Fri, 30 May 2014, Luke Kenneth Casson Leighton wrote:
On Thu, May 29, 2014 at 11:20 PM, Stéphane Goujet stephane.goujet@wanadoo.fr wrote:
On Thu, 29 May 2014, Luke Kenneth Casson Leighton wrote:
BOM and schematic PDF are here, review appreciated.
I can get the BOM, but not the PDF : You don't have permission to access
sorted.
Thanks.
A few quick remarks:
*1* ACIN: should be renamed DCIN, I guess.
*2* PW_EN: when connected to U9 its wire has an output symbol. It should be an input symbol.
*3* PW_EN: not generated anywhere yet.
*4* resistors around U9: R53 and R54 have very high values (they are usually chosen around the range 10k-100k, not 100k-1M). Was there an advise to do so, or a reference design doing so ?
*5* RESET circuit: I do not quite understand it. First, because VCC-3V3 depends on PW_EN (U9 switching regulator). Second, because you seem to assert RESET (RESET#=0) when PW_EN==1: is this what you really want ? Third, because... what is RESET# used for ?
Or did you believe EN was an output of SY8008B ? That would explain remarks 2, 3 and 5. But it is an input.
Goodbye, Stéphane.
On Fri, May 30, 2014 at 12:31 PM, Stéphane Goujet stephane.goujet@wanadoo.fr wrote:
On Fri, 30 May 2014, Luke Kenneth Casson Leighton wrote:
On Thu, May 29, 2014 at 11:20 PM, Stéphane Goujet stephane.goujet@wanadoo.fr wrote:
On Thu, 29 May 2014, Luke Kenneth Casson Leighton wrote:
BOM and schematic PDF are here, review appreciated.
I can get the BOM, but not the PDF : You don't have permission to access
sorted.
Thanks.
A few quick remarks:
*1* ACIN: should be renamed DCIN, I guess.
yes.
*2* PW_EN: when connected to U9 its wire has an output symbol. It should be an input symbol.
the whole power enable and reset is up for grabs at the moment because it is tied to the modifications that are needed for the CPU Card and the EOMA68 interface.
so, RESET will be renamed "power on" and will get connected directly to the EOMA68 interface, on HIGH and connected to one of the 5V lines behind a resistor so that things don't go totally tits-up if people use the Revision 1 CPU cards.
more later.
l.
On Fri, May 30, 2014 at 12:31 PM, Stéphane Goujet stephane.goujet@wanadoo.fr wrote:
On Fri, 30 May 2014, Luke Kenneth Casson Leighton wrote:
On Thu, May 29, 2014 at 11:20 PM, Stéphane Goujet stephane.goujet@wanadoo.fr wrote:
On Thu, 29 May 2014, Luke Kenneth Casson Leighton wrote:
BOM and schematic PDF are here, review appreciated.
I can get the BOM, but not the PDF : You don't have permission to access
sorted.
Thanks.
A few quick remarks:
*1* ACIN: should be renamed DCIN, I guess.
*2* PW_EN: when connected to U9 its wire has an output symbol. It should be an input symbol.
*3* PW_EN: not generated anywhere yet.
*4* resistors around U9: R53 and R54 have very high values (they are usually chosen around the range 10k-100k, not 100k-1M). Was there an advise to do so, or a reference design doing so ?
finally got round to looking at this, yes it's the reference design. the values are chosen to give the voltage required, there is a table (and a calculation) in the ref. design.
*5* RESET circuit: I do not quite understand it. First, because VCC-3V3 depends on PW_EN (U9 switching regulator). Second, because you seem to assert RESET (RESET#=0) when PW_EN==1: is this what you really want ? Third, because... what is RESET# used for ?
i'm going to remove it. poweroff will be "reset".
arm-netbook@lists.phcomp.co.uk
-
Alexander Stephen Thomas Ross -
Boris Barbour -
Christopher Havel -
Dominique Dumont -
Luke Kenneth Casson Leighton -
Stéphane Goujet