I have tried to connect an external hard drive to the second generation apple tv with little success because I can not find a HDMI cable that allows the MicroUSB slot to be used. The size of the HDMI connector blocks the MicroUSB port. Has anyone found a brand of HDMI cable that allows a microUSB cable to be connected and if so, did the aTV Flash program recognize the files on the external HD?
There is no point in even trying!
The micro-USB port is only capable at the hardware level as acting as a slave device. To drive a USB disk it would need to be capable of acting as a host device.