I use FPGAs to implement USB1.0 phy and application layer. The application is debugging with a normal Logitech K120 keyboard. Now, I could send a SETUP packet to light up the NUM, CAPS and SCROLL lock LED with no problem.
But when I send a INTERRUPT packet to enable device report, the bus is to wait, and then get timeout fail.
SET Configuration is 1.
The INTERRUPT packet is as follows:
< SYNC >< IN ><ADR0 > EP1 CRC5
00000001100101100000000100000101
< 0 8 >< 9 6 >< 0 ><1 ><CRC>
Why could it not work?
I would really appreciate it if you would help.