DS
_FT311D
USB ANDROID HOST IC Datasheet
Version 1.0
Document No.: FT_000660 Clearance No.: FTDI#
305
6
USB Error Detection
Pin 32 (IOBUS7) of the device is provided to indicate a problem has occurred with the USB connection.
Typical errors include USB Device Not Supported, which would occur if the USB port was connected to a
non-Android class device port e.g. the FT311D is not designed to host memory sticks or printers etc. USB
Device Not Responding and Hub not supported would be reported also if connected to a hub. The signal
states are as follows:
Pin state
Logic 0
Logic 1
One 50ms logic 0 pulse
Definition
Device connected to USB and functional
Device not connected
Device not responding. This pulse occurs at plug-in
and then the signal returns to logic 1. This then
repeats at a 1 second interval.
Device not supported. These pulses occur at plug-
in and then the signal returns to logic 1. This then
repeats at a 1 second interval.
Hub not supported. These pulses occur at plug-in
and then the signal returns to logic 1. This then
repeats at a 1 second interval.
Two 50ms logic 0 pulses
Three 50ms logic 0 pulses
Table 6.1 Error Detection
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