usbusb deviceusb-host
I am attempting a project that is a basic usb keyboard logger. I plan on using a PIC32 microcontroller that has built in USB host capabilities to interface to the keyboard.
My question is, can i hang off in parallel my MCU to read the data lines without affecting what is sent to the computer? See the below picture.
Is this acceptable practice, or does the data need to be fed in series from the input->mcu->output connector? Any issues with current draw?
Thanks!
There is a development kit microchip that performs with all the technical features that you require, it is USB Starter Kit II
In the picture I have marked the 3 USB ports (1 debug only) and the jumper to select the power source
The kit is very good documented, the datasheet contains all the schematics and there are numerous "Application Notes" on how to realize both the hardware this software. It can be used as the basis, for your study.
If you did not find any interesting application with its own code of microcontroller, can try to search in other families as PIC24F and PIC24H will notice that with a few changes in the layer configuration of hardware will be able to reuse the code without any problems.
For the software, I definitely think that Linux would be the way to go. The reasons I would choose it over android are threefold:
The GUI problem is a major consideration. However, you are in luck. If you (or someone in your team) is familiar with C, writing a GUI in GTK+ would be the easy way out. This requires installing a bit more software (X, GNOME) than is ideal for an embedded platform, but all things considered I think it is the best way.
Hope this helps!
Best Answer
No, this will not work. You will need either a µC with two USB ports (one host, one device mode) or two controllers.
USB works with exactly one host on a bus, and when you want multiple devices you have to use a hub. Note that a PC is always in host mode.