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Kamikaze47
- 29th June 2007, 19:18
Would be good for PBP to support composite USB devices.

sebapostigo
- 18th January 2008, 15:46
PicKit 2 support, for example

skimask
- 18th January 2008, 15:53
Would be good for PBP to support composite USB devices.

It's not really a function of PBP to support USB, whether it's master, slave or composite. That's mainly a function of the hardware in the PIC itself. If the PIC can't handle a Master USB device, then PBP won't be able to handle it, at least not without extra external hardware support (i.e. the new Vinculum chips).
Yes, PBP does support limited USB communications on PICs with built-in USB hardware, those are Slave USB ports, meaning that you still need a Host/Master type device (i.e. PC, Vinculum chip, or otherwise) to successfully communicate externally with that device.

Darrel Taylor
- 18th January 2008, 19:59
composite USB devices means there are more than 1 USB connection from the same device.

Could be 1 is HID, and another is user defined, like an audio channel or something with it's own driver.

Has nothing to do with Master and Slave.
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skimask
- 18th January 2008, 20:01
composite USB devices means there are more than 1 USB connection from the same device.
Could be 1 is HID, and another is user defined, like an audio channel or something with it's own driver.
Has nothing to do with Master and Slave.
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I was taking 'composite' in exactly that context, as in, one device is both master and slave.

Darrel Taylor
- 18th January 2008, 20:36
Well that wouldn't make much sense.

You can only have 1 master on a USB bus.
So there's nothing else to access the slave part of your master/slave composite.
Unless it's going to access itself.
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skimask
- 18th January 2008, 20:47
Well that wouldn't make much sense.
You can only have 1 master on a USB bus.
So there's nothing else to access the slave part of your master/slave composite.
Unless it's going to access itself.
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I've got this wireless hard drive with 2 USB ports...
One USB port is for plugging in a 'thumbdrive', it copies the contents onto the local drive (Host mode).
The other USB port is for plugging it into a PC, and making the box into an external drive (Slave mode).
Obviously, you can't do both at once (plug in a 'thumbdrive' and access it thru the wireless hard drive, like there's 2 drives). I suppose, in theory, if the firmware was written correctly, the thing could access itself, somehow, I guess. But that would almost need 2 seperate USB controllers.

Darrel Taylor
- 18th January 2008, 21:02
Your drive has it's own Host controller.
But you can't connect that to the main USB bus. Only external Slave devices.

Anyhow, the original question from Kamikaze47 was about composite USB devices, such as shown in microchip's TB057. Although they call it "Combination devices".

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en011986

Which is possible with PBP, but not directly supported.
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skimask
- 18th January 2008, 21:15
Your drive has it's own Host controller.
But you can't connect that to the main USB bus. Only external Slave devices.

Yes, true, and that's what I thought was meant by 'composite USB', able to Host and Slave in the same box, but not at the same time.
And yes, I can connect the box's internal hard drive to the PC thru the USB (thumbdrive port is dead, hard drive is slave)...and I can connect the thumbdrive to the PC thru the USB connections (hard drive port must act as a signal pass thru to the thumbdrive port or something, not sure)...and I can connect the thumbdrive to the hard drive by plugging it in (the PC port is dead, hard drive is master, thumbdrive port is slave).
I just can't do any combination of any of the three at any one time.

PJALM
- 17th May 2008, 23:19
I think he still doesn't understand what a composite device is. Composite devices are slave only but are multiple slaves, for example, an HID mouse and keyboard in the same device like the USB to PS/2 converters or even maybe 2 PS/2 ports, a joystick port and a serial port in same device.

skimask
- 18th May 2008, 05:31
I think he still doesn't understand what a composite device is.
You're right...
I don't have a clue about the difference between master, slave, and composite devices...

PJALM
- 18th May 2008, 07:51
Sorry didn't mean no disrespect, just trying to help