Interrupt Status Register (Usbx_Istat) - NXP Semiconductors MKL27Z128VFM4 Reference Manual

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This bit is set if host mode is enabled.

33.5.5 Interrupt Status register (USBx_ISTAT)

Contains fields for each of the interrupt sources within the USB Module. Each of these

fields are qualified with their respective interrupt enable bits. After an interrupt bit has

been set it may only be cleared by writing a one to the respective interrupt bit. This

Address: 4007_2000h base + 80h offset = 4007_2080h

Stall Interrupt

In Target mode this bit is asserted when a STALL handshake is sent by the SIE.

This field is reserved.

This read-only field is reserved and always has the value 0.

This bit is set when a K-state is observed on the DP/DM signals for 2.5 µs. When not in suspend mode

this interrupt must be disabled.

This bit is set when the USB Module detects a constant idle on the USB bus for 3 ms. The sleep timer is

reset by activity on the USB bus.

This bit is set when the current token being processed has completed. The processor must immediately

read the STATUS (STAT) register to determine the EndPoint and BD used for this token. Clearing this bit

(by writing a one) causes STAT to be cleared or the STAT holding register to be loaded into the STAT

This bit is set when the USB Module receives a Start Of Frame (SOF) token.

This bit is set when any of the error conditions within Error Interrupt Status (ERRSTAT) register occur. The

processor must then read the ERRSTAT register to determine the source of the error.

This bit is set when the USB Module has decoded a valid USB reset. This informs the processor that it

should write 0x00 into the address register and enable endpoint 0. USBRST is set after a USB reset has

been detected for 2.5 microseconds. It is not asserted again until the USB reset condition has been

removed and then reasserted.

Freescale Semiconductor, Inc.

USBx_ADDINFO field descriptions (continued)

USBx_ISTAT field descriptions

KL27 Sub-Family Reference Manual , Rev. 5, 01/2016

Chapter 33 Universal Serial Bus (USB) FS Subsystem