v-usb boot loaders mega168 compatible

[josheeg]

v-usb boot loaders mega168 compatible....
this would make bare bones board arduino compatible without a FTDI.
Also it would make it cheaper all through-hole parts.
Also they show how to make the programer work with the wiring arduino ide...
now if their was some libraries for accesssing the keyboard or mouse output from the device and maby to switch from a output interface like a mouse or keyboard to pc to a pc to switches interface.
What speeds higher than emulated serial by usb ftdi chip would this allow if the keypad option was used to bring in 16 bits? shown in a v-usb example hid keys.

[oz]

I'm not following this suggestion.
I know in theory that it is possible to put the USB function into the Atmega chip, at the cost of some ram and a performance hit of some kind.
Has someone done this with Atmega 328's? I've seen some done with other Atmel chips - that I think had some hardware on chip that made this easier.

While it adds some convenience and cost savings on projects that are tethered to a laptop/desktop, I think my approach of programming module / microcontroller is simpler, and easier to understand. I see the "on chip" USB as being fairly inevitable sometime though as prices fall on more powerful chips. Maybe the USB capability will get moved into on-chip hardware, if it hasn't already.

Paul

[josheeg]

it has been done sparkfun had a tutorial you can find if you search under tutorials on the radio button then type in avr stick. That avr stick is not what they use in the tutorial they use a mega 168 at 16mhz. they said it would work with the mega3xx. <- newer arduino. Their aso is a example called HIDKeys on v-usb 's site. But spark fun has code to make a HID USB mouse. The keys are useful because as a data logger it could tipe output to the keyboard out the screen a spread sheet or c program that gets keys and writes it to a file.

[bperrybap]

Paul,
I've seen sample projects with the V-usb/USBTiny stuff working on ATtiny45s with no crystal.
Really nice for that environment as you can get a full USB serial connection to the host
using the serial CDC without needing any additional USB->serial hardware.

So it definitely could work on something like a BBB or RBB design.

It's dirt simple to implement. A few resistors and a USB connector in the simplest case
and a few more diodes in others.

Maybe an alternative for something like a BBB board would be to have a USB
"module" board that could plug into the analog pins to offer something to those that want V-USB
support??

I'm looking at building a small protoboard to play around with it out on my BBB myself.


---bill

[oz]

I'm less puzzled about how the hardware works (which seems fairly simple) than how the software would work. In particular, how big a hit the processor takes to service the USB. Seems like it would need to be interrupt driven not to miss anything.

Paul