Thanks for comments, Ytai ! I understand your point in servo connection, but would it be possible to make a slight modification, that does not increase the size of the board: if the 3 pin rows of 3 and 5V are switched, and pin 45 is moved "up" to second row, it could be possible to connect easily 2 servos to 45,46 pins ! Of course this assumes that 5V can tolerate 2 servos.
tiistai 1. joulukuuta 2015 19.49.10 UTC+2 Ytai kirjoitti: > > Thanks for the feedback, I agree with most of it, see inline. > > On Tue, Dec 1, 2015 at 2:22 AM, <[email protected] <javascript:>> > wrote: > >> If I manage to desolve one of those components, is the IOIO board still >> functional, when powered (5V) using 5V pin ? >> For me, powering the IOIO and servos has been the biggest problem. >> The main requirements are: >> - IOIO could be powered using the standard 12V power adapter for "fixed" >> projects >> > > Yes, this is possible. Up to 15V is supported. Due to a bug you're already > aware of the recommendation has been not to exceed 10V, but this bug is > believed to have been fixed and the new units are shipping soon from > SparkFun and SeeedStudio. > > >> - in "mobile" projects, using either Lipo (7.4V) or LifePo(6.6V) battery >> > > Yes, this is possible. > > >> - it should be possible to SAFELY connect 3-4 servos to 5V connector in >> IOIO and run these servos concurrently. May be a place for an appropriate >> fuse should be added to limit the current and not damage the IOIO >> > > The "3-4 servos" requirement is arbitrary. The next person is going to > require 8 servos, and you see where it goes... The IOIO have a 3A > regulator, which seemed to be a good trade-off between utility, cost and > board space. Whatever load fits in this budget, great! Whatever doesn't, > you can always use an external regulator. It is quite possible that you can > use 4 standard size servos within 3A. This would depend on the actual > servos, their gear ratio and the load. In either case, I agree that a > current overload should not permanently damage the board. This is believed > to be addressed by the new revision. One thing to ensure is that your > motors do not badly surge the voltage as result of sudden changes in > current. In case they do, proper protection is your responsibility (e.g. > large capacitors and shottky diodes). > > >> - another nice to have feature (even the physical size of IOIO board must >> be increased): in P-pins where PWM is possible, there could be ground and >> 5V pins, so that I can solve 3-pin male connector and connect the standard >> servo 3-pin female connector. This would make it easier to connect servos. >> > > People have done that with "shields" etc. I don't see as servos being > special in any way and the trade-off would be increasing board size and > cost, which might have the next person complain about why the board is > bigger than necessary while they don't actually use it to drive servos. I > tried to keep the IOIO focused on being generic, with the assumption that > for application specific requirements, people can always implement shields > / mother-boards or spin their own version of the board, while using the > same software stack. > > >> >> When will the new hardware revision available? >> > > I cannot speak for the manufacturers. They might be waiting to finish > existing stocks before selling the new revision, etc. At least from my end, > I have gone through sufficient testing of the new revision from both main > manufacturers and am pleased with it. I know for certain that both are not > going to manufacture more of the old boards, so it is only a question of > when the next batch comes out. > > >> Can you consider these modifications, Ytai ? >> > > I believe the new revision would meet most of your requirements as-is, > except for the servo-specific features, which I disagree with. Hope you > understand my reasoning. > > >> >> >> >> >> perjantai 13. marraskuuta 2015 22.36.54 UTC+2 Ytai kirjoitti: >>> >>> The switcher is the small square IC next to the power connector, which >>> has no legs. The inductor is the large-ish cylindrical component next to it. >>> A new hardware revision of the IOIO will roll out very soon, which >>> addresses this issue. Until then, the advice is to not power the IOIO with >>> more than 10V. >>> >>> On Fri, Nov 13, 2015 at 9:25 AM, <[email protected]> wrote: >>> >>>> I have exactly the same problem in 2 of my IOIO boards. If it is >>>> powered using VIN->not working. If 5-5.5v supply is connected to 5v pin. >>>> The power led will be on, but not working, and the processor gets hot. The >>>> resistance between GND and 5V is nearly 0 (compared to functioning board >>>> 1-2 MOhm). >>>> So what is the switcher to be eliminated to rescue the board ? The >>>> micro switch near USB connector ? >>>> >>>> perjantai 13. marraskuuta 2015 9.28.17 UTC+2 Ytai kirjoitti: >>>>> >>>>> It does sound like a fried switcher, causing a low impedance path >>>>> between 5V and ground. This is likely causing your 5V rail to sag, so it >>>>> might explain why your Android won't connect. One way to hack around this >>>>> problem is to desolder the switcher or the inductor. I would first verify >>>>> this guess by measuring resistance between 5V and GND when not powered, >>>>> and >>>>> expect that you'll see a low value in the few ohm or less range. >>>>> >>>>> On Thu, Nov 12, 2015 at 2:57 PM, Zvonimir Udovičić <[email protected] >>>>> > wrote: >>>>> >>>>>> >>>>>> >>>>>> Dana četvrtak, 12. studenoga 2015. u 17:50:08 UTC+1, korisnik Tyler >>>>>> napisao je: >>>>>>> >>>>>>> Okay, can you give us more detail? When you power the IOIO, are any >>>>>>> of the lights coming on? How are you powering the IOIO, specifically, >>>>>>> where >>>>>>> are you applying the 5v? Finally, does any part of the IOIO board feel >>>>>>> very >>>>>>> hot? >>>>>>> >>>>>>> >>>>>>> power lamp lights normally, i am powering ioio with 5V adapter on >>>>>> 5V pin, ioio board feels hot and vin pin is not working >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "ioio-users" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to [email protected]. >>>>>> To post to this group, send email to [email protected]. >>>>>> Visit this group at http://groups.google.com/group/ioio-users. >>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>> >>>>> >>>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "ioio-users" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To post to this group, send email to [email protected]. >>>> Visit this group at http://groups.google.com/group/ioio-users. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- >> You received this message because you are subscribed to the Google Groups >> "ioio-users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at http://groups.google.com/group/ioio-users. >> For more options, visit https://groups.google.com/d/optout. >> > > -- You received this message because you are subscribed to the Google Groups "ioio-users" group. 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