Hi,
Regarding USB-A003 errata on P1010, why the value of 300usec is advised ?
Could this value depends on HW implementation ? Could it depend on USB 2.0 connected devices ?
Is it possible to check if this value is the best value for non blocking PHY ?
What could the impact of greater value than 300usec ?
Could less than 300 usec lead to NOPID transmit command immediately followed by a STP pulse ?
Thanks in advance for your reply,
Regards,
Fabrice DECROP LONGET
Our 3rd party vendor reported to us the illegal NOPID TxCMD is caused by "at the end of reset (end of chirp back from Host), when the protocol engine sends a SOF, the ULPI port control sends the SOF to the PHY before sending the update OpMode command. This issue can be avoided by adding 300 uSec after the USB reset. They have not been able to duplicate this problem since then. However, they did go through the verilog code.
Have a great day,
TIC
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