Lantronix DSTni-EX - Manual (Page 48)

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Bits Field Name Description
8 USB_RST Enable/Disable USB_RST Interrupt
1 = enable the USB_RST interrupt.
0 = disable the USB_RST interrupt (default).
7 STALL Stall
Used in target and host modes.
• In target mode, it asserts when the SIE sends a stall handshake.
• In host mode, it is set if the USB detects a stall acknowledge during the
handshake phase of a USB transaction.
This interrupt is useful if the last USB transaction completed successfully or
stalled.
6 ATTACH Detect Attach of a USB Peripheral
1 = USB detects an attach of a USB peripheral.
Only valid if HOST_MODE_EN is true. This interrupt signals a peripheral is now
present and must be configured. The ATTACH interrupt asserts if there are no
transitions on the USB for 2.5us and the current bus state is not SE0.
0 = USB does not detect an attached USB peripheral.
5 RESUME Resume
This bit is set when the device can resume operation.
4 SLEEP Sleep Timer
1 = USB detects constant idle on the USB bus signals for 3 ms.
Activity on the USB bus resets the sleep timer.
0 = USB does not detect constant idle.
3 TOK_DNE Token Processing
1 = the current token being processed is complete. The microprocessor should
read the STAT register immediately to determine the endpoint and BD used for
this token. Clearing this bit (by writing a 1) clears the STAT register or loads the
STAT holding register into the STAT register.
0 = token processing is not occurring or has not been completed.
2 SOF_TOK Start-of-Frame Token
1 = USB receives a Start-of-Frame (SOF) token.
0 = USB has not received a Start-of-Frame (SOF) token.
1 ERROR Error Condition
1 = an error condition occurred in the ERR_STAT register. The microprocessor
must read the ERR_STAT register to determine the source of the error.
0 = an error condition did not occur.
0 USB_RST USB Reset
1 = USB decodes a valid USB reset. The microprocessor writes 00h in the
address register and enables endpoint 0.
USB_RST is set when a USB reset is detected for 2.5 microseconds. It is not
asserted again until the USB reset condition is removed and reasserted.
0 = USB is not decoding a valid USB reset.