Hello Everyone,
I'm having a problem where we can't seem to get the hub to be recognized through windows XP OS. Device manager says ‘device not recognized’. So we know that there is communication between the part and the computer.
In double checking the schematic we did realize that we handled the reset differently (not on purpose). At first we didn't hook the RESET# signal to anything. After initially seeing this and seeing it not work, we tied it high via a 10K ohm.
We know the data sheet called out a certain time window that RESET# needed to be asserted.
From the datasheet ------
RESET is an active low TTL input with hysteresis and must be asserted at power up. When
RESET 4 I RESET is asserted, all logic is initialized. Generally, a reset with a pulse width between 100 μs and 1 ms is recommended after 3.3-V VCC reaches its 90%. Clock signal has to be active during
the last 60 μs of the reset window.
Can I get around this issue by adding a reset button to my design? How critical is the reset?