stall control register and In/out ready clear flag of endpoint 0
| CLRRDY | When the MXPLD register is set by user, it means that the endpoint is ready to transmit or receive data. If the user wants to turn off this transaction before the transaction start, users can set this bit to 1 to turn it off and it is auto clear to 0. For IN token, write 1 is used to clear the IN token had ready to transmit the data to USB. For OUT token, write 1 is used to clear the OUT token had ready to receive the data from USB. This bit is write 1 only and it is always 0 when it was read back. |
| SSTALL | 1 = Set the device to respond STALL automatically 0 = Disable the device to response STALL |