Lantronix DSTni-EX Enable/Disable USBRST Interrupt, Stall, Detect Attach of a USB Peripheral

Models: DSTni-EX

1 95
Download 95 pages 56.41 Kb
Page 48
Image 48

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.

40

Page 48
Image 48
Lantronix DSTni-EX manual Enable/Disable USBRST Interrupt, Stall, Detect Attach of a USB Peripheral, Resume, Sleep Timer