Re: USB Host - Class 1 Bluetooth
Why yes, that's it. If it looks OK there then you should be OK. Of course, it's a very long document. I think I managed to read the whole thing (usb_20.pdf) at one point, however I was asleep through most of it. :-) I spent most of my time in chapter 7 since I was designing and characterizing the pads. I also notice that there are a lot more files available. Back then there were about half as many. And OTG was just a proposal. -- Allen Brown http://brown.armoredpenguin.com/~abrown Hi, --- On Tue, Jun 17, 2008 at 5:33 AM, Allen Brown [EMAIL PROTECTED] wrote: | Also the host (i.e. Nokia) may not allow a device to come on | if it reports needing more than the host *thinks* it is capable | of. \-- Section: 7.2.1.4: High-power Bus-powered Functions, pp. 174 ? [1] If sufficient power exists, the remainder of the function may be powered on. --- | If you can your hands on a copy of the USB spec, do so. Unfortunately | that may be difficult. They want you to pay money to play in that | game. \-- This one? [1] usb_20.pdf. http://www.usb.org/developers/docs/. SK -- Shakthi Kannan http://www.shakthimaan.com ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
Re: USB Host - Class 1 Bluetooth
Hello All, If I'm out of frame here let me know. But it does seem that a powered hub would resolve the issue quite nicely. There may also be a software hack also that allows the kernel to ignore the power requirements. I do remember seeing power assesment code, in the musb driver source. However, disabling that check in the kernel is a *bad* idea. Real USB OTG hardware is used to receiving signals down the +V pin. (That's how it sends host-peripheral negotiation). So a host-host hookup is unlikely to destroy OTG hardware, but non-compliant hardware could theoretically get fried. I'm unfamiliar with the 770 hardware and whether it is fully OTG compliant or not. But a hub is the safest bet. cheers, Charles Werbick On Mon, Jun 16, 2008 at 5:22 PM, Daniel Blackburn [EMAIL PROTECTED] wrote: I don't think the power should be an issue as Bluetooth adapters shouldn't be much more demanding that other USB devices that people have got working with the 770. I am using a circuit similar to this one, http://www.hcilab.org/projects/nokia770/nokia770.htm. I will test my circuit with other simpler USB devices with comparable power usage but I think the problems will be more related to software than hardware. I don't have much experience with drivers on Linux so that is the bit were I am worried I might have overlooked something crucial. Cheers, Dan Allen Brown wrote: This is tangential to what you are asking about, but I think you could run into a problem with your power injector. It's been a few years since I read the USB specs, but as I recall the host knows, and makes decisions based on, what power is available. Also it switches that power on and off depending on what state the bus is in. There could be problems if the actual power doesn't match what the host thinks it is. ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
USB Host - Class 1 Bluetooth
I am interested in using class 1 USB bluetooth adapters in Maemo. So far I have flashed a 770 with the latest OS2007 hacker edition and enabled USB host mode. I have also built a power injector to provide attached USB devices with 5v. I am now looking at how to get a suitable driver for the hardware and then setting up BlueZ to use the attached adapter instead of the 770's internal class 2 adapter. Does this seem like a feasible approach to you Maemo gurus? I'm getting better/faster at working in Linux/Maemo but progress is still slow. Any tips greatly appreciated as they will probably save me a lot of time. Does anyone know of any people or projects attempting anything similar? I surely can't be the first to try this, other people must have looked at class 1 bluetooth for these devices. If not is this interesting to anyone else? Thanks, Dan ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
Re: USB Host - Class 1 Bluetooth
This is tangential to what you are asking about, but I think you could run into a problem with your power injector. It's been a few years since I read the USB specs, but as I recall the host knows, and makes decisions based on, what power is available. Also it switches that power on and off depending on what state the bus is in. There could be problems if the actual power doesn't match what the host thinks it is. -- Allen Brown http://brown.armoredpenguin.com/~abrown I am interested in using class 1 USB bluetooth adapters in Maemo. So far I have flashed a 770 with the latest OS2007 hacker edition and enabled USB host mode. I have also built a power injector to provide attached USB devices with 5v. I am now looking at how to get a suitable driver for the hardware and then setting up BlueZ to use the attached adapter instead of the 770's internal class 2 adapter. Does this seem like a feasible approach to you Maemo gurus? I'm getting better/faster at working in Linux/Maemo but progress is still slow. Any tips greatly appreciated as they will probably save me a lot of time. Does anyone know of any people or projects attempting anything similar? I surely can't be the first to try this, other people must have looked at class 1 bluetooth for these devices. If not is this interesting to anyone else? Thanks, Dan ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
Re: USB Host - Class 1 Bluetooth
I don't think the power should be an issue as Bluetooth adapters shouldn't be much more demanding that other USB devices that people have got working with the 770. I am using a circuit similar to this one, http://www.hcilab.org/projects/nokia770/nokia770.htm. I will test my circuit with other simpler USB devices with comparable power usage but I think the problems will be more related to software than hardware. I don't have much experience with drivers on Linux so that is the bit were I am worried I might have overlooked something crucial. Cheers, Dan Allen Brown wrote: This is tangential to what you are asking about, but I think you could run into a problem with your power injector. It's been a few years since I read the USB specs, but as I recall the host knows, and makes decisions based on, what power is available. Also it switches that power on and off depending on what state the bus is in. There could be problems if the actual power doesn't match what the host thinks it is. ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
Re: USB Host - Class 1 Bluetooth
I think you didn't understand what I was saying. I'm not saying the device will draw more power than your injector can handle. I am saying that turning the power on and off is a part of the protocol. And messing with this can break things. Also the host (i.e. Nokia) may not allow a device to come on if it reports needing more than the host *thinks* it is capable of. Not sure about this. When I was reading the USB spec I was focussed on the electronics, not the software. If you can your hands on a copy of the USB spec, do so. Unfortunately that may be difficult. They want you to pay money to play in that game. -- Allen Brown http://brown.armoredpenguin.com/~abrown I don't think the power should be an issue as Bluetooth adapters shouldn't be much more demanding that other USB devices that people have got working with the 770. I am using a circuit similar to this one, http://www.hcilab.org/projects/nokia770/nokia770.htm. I will test my circuit with other simpler USB devices with comparable power usage but I think the problems will be more related to software than hardware. I don't have much experience with drivers on Linux so that is the bit were I am worried I might have overlooked something crucial. Cheers, Dan Allen Brown wrote: This is tangential to what you are asking about, but I think you could run into a problem with your power injector. It's been a few years since I read the USB specs, but as I recall the host knows, and makes decisions based on, what power is available. Also it switches that power on and off depending on what state the bus is in. There could be problems if the actual power doesn't match what the host thinks it is. ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
Re: USB Host - Class 1 Bluetooth
Hi, --- On Tue, Jun 17, 2008 at 5:33 AM, Allen Brown [EMAIL PROTECTED] wrote: | Also the host (i.e. Nokia) may not allow a device to come on | if it reports needing more than the host *thinks* it is capable | of. \-- Section: 7.2.1.4: High-power Bus-powered Functions, pp. 174 ? [1] If sufficient power exists, the remainder of the function may be powered on. --- | If you can your hands on a copy of the USB spec, do so. Unfortunately | that may be difficult. They want you to pay money to play in that | game. \-- This one? [1] usb_20.pdf. http://www.usb.org/developers/docs/. SK -- Shakthi Kannan http://www.shakthimaan.com ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
