Arduino Pro Mini Questions

[dr0p]

Okay, well here's what I want to do:

I want to have a serial USB (I know, redundant) connection to the microprocessor that occasionally spits data at the processor, and I would like the processor to then save that data on to a USB key.

Anyways, I needed the smallest processor available, so I figured with its two digital connections that the Arduino Pro Mini would be able to handle this but I'm not entirely sure, so I was wondering if anyone here had some advice on this, specifically is it even possible with this hardware? Would there be an better or easier piece of hardware to use for this task?

Thanks~

[dallaskorben]

If you want to connect a USB key to the microcontroller, the microcontroller will need to be able to act as a USB host. I don't know if there is a real cheap/simple way to do that.

If you're willing to use an SD card, I think they usually are simple to interface with microcontrollers. A quick google found a thread on the Arduino forum that seems to cover reading/writing an SD card. (I have only played with an Arduino Duemilanove a bit, I'm not familiar with the other Arduino devices, and I haven't tried interfacing SD with it)

An Arduino would work well for the USB connection to PC (as would a Teensy - it's also small and cheap). You might want to look around on Avrfreaks.net, it's a great site to check for information and projects using AVR chips (there may be a project similar to what you want, that you can modify) and the forums are very helpful too.

To read/write a USB key is possible but I think it would require more hardware than just an Arduino (a USB host), and I think in most cases it would be considerably more cost/trouble compared to using SD.

[dr0p]

If you want to connect a USB key to the microcontroller, the microcontroller will need to be able to act as a USB host. I don't know if there is a real cheap/simple way to do that.

If you're willing to use an SD card, I think they usually are simple to interface with microcontrollers. A quick google found a thread on the Arduino forum that seems to cover reading/writing an SD card. (I have only played with an Arduino Duemilanove a bit, I'm not familiar with the other Arduino devices, and I haven't tried interfacing SD with it)

An Arduino would work well for the USB connection to PC (as would a Teensy - it's also small and cheap). You might want to look around on Avrfreaks.net, it's a great site to check for information and projects using AVR chips (there may be a project similar to what you want, that you can modify) and the forums are very helpful too.

To read/write a USB key is possible but I think it would require more hardware than just an Arduino (a USB host), and I think in most cases it would be considerably more cost/trouble compared to using SD.

Actually I was stumbling around the arduino site and came accross this which is more or less a USB r/w library that's quite easily used on all of the arduinos.

New question though:

If I were to have an analog video coming in to the arduino on one or two of its analog inputs would it be a powerful enough device to convert it to a digital video in real-time and save it to the usb?

[dallaskorben]

If I were to have an analog video coming in to the arduino on one or two of its analog inputs would it be a powerful enough device to convert it to a digital video in real-time and save it to the usb?

I'm pretty sure the Arduino is not powerful enough to handle video. Maybe there is a chip or board that can handle the conversion from analog to digital video, which the Arduino could control. But I don't think you could pass all the data through the Arduino, I don't think it's fast enough to keep up - even if you had a codec that was feeding the Arduino compressed video, I think the Arduino would still be too slow. (and probably the speed it can write to a memory stick isn't very fast)

[dr0p]

I'm pretty sure the Arduino is not powerful enough to handle video. Maybe there is a chip or board that can handle the conversion from analog to digital video, which the Arduino could control. But I don't think you could pass all the data through the Arduino, I don't think it's fast enough to keep up - even if you had a codec that was feeding the Arduino compressed video, I think the Arduino would still be too slow. (and probably the speed it can write to a memory stick isn't very fast)

Yeah I didn't think it would be able to handle it ether... could you recommend another chip that would be able to do it though?

[dallaskorben]

Yeah I didn't think it would be able to handle it ether... could you recommend another chip that would be able to do it though?

I don't know what the best choice might be, I imagine it will have to be a 32-bit platform (like ARM, or AVR32). I have one of these: http://www.atmel.com/dyn/products/tools_ca...sp?tool_id=4102 - ATNGW100 development board for AVR32. It runs Linux and is quite powerful and small, but not as inexpensive as something like an Arduino. (ATNGW100 sells for about $90, and I think you might have to add some hardware to interface between the video source and the ATNGW100) There are also various ARM development boards that may be interesting. (AVR32 is relatively new and is Atmel-only, ARM is more widespread and different manufacturers make ARM chips)

Maybe a small form factor PC would do the job? (something with a nano-ITX board or something else small) That would sure make the USB stuff and video capture easy to put together.

What resolution of video do you want to capture, and at what framerate?