Bits

Field Name

Description

12

RESET

USB Reset Signal

 

 

1

= enables the USB to generate USB reset signaling. This allows the USB to

 

 

reset USB peripherals. This control signal is only valid in host mode, (i.e.,

 

 

HOST_MDOE_EN=1). Software must set RESET to 1 for the required amount of

 

 

time and then clear it to 0 to end reset signaling. For more information about

 

 

RESET signaling, see Section 7.1.4.3 of the USB specification version 1.0.

11

HOSTMODE EN

Host Mode Enable (valid for host mode only)

 

 

1

= enables the USB to operate in host mode. In host mode, the USB performs

 

 

USB transactions under the programmed control of the host processor.

 

 

0

= USB not enabled for host mode.

10

RESUME

Resume Signaling

 

 

1

= allows the USB to execute resume signaling. This lets the USB perform

 

 

remote wake-up. Software must set RESUME to 1 for the required amount of time

 

 

and then clear it to 0. If the HOST_MODE_EN bit is set, the USB appends a Low

 

 

Speed End-of -packet to the Resume signaling when the RESUME bit is cleared.

 

 

For more information about RESUME signaling, see Section 7.1.4.5 of the USB

 

 

specification version 1.0.

 

 

0

= prevents the USB from executing resume signaling.

9

ODD_RST

BDT PDD Reset

 

 

1

= resets all the BDT ODD ping/pong bits to 0, which then specifies the EVEN

 

 

BDT bank.

 

 

0

= does not reset the BDT ODD ping/pong bits.

8

USB_EN

USB Enable

 

 

1

= enables the USB to operate, clearing it will disable the USB. It causes the SIE

 

 

to reset all of its ODD bits to the BDTs. Therefore, setting this bit resets much of

 

 

the logic in the SIE. When host mode is enabled clearing this bit causes the SIE

 

 

to stop sending SOF tokens.

7:4

ENDP

Encode Endpoint

 

 

Encode the endpoint address receiving or transmitting the previous token. This

 

 

lets the microprocessor determine which BDT entry is updated by the last USB

 

 

transaction. These four bits correspond to the endpoint address 3:0, respectively.

3

TX

Last Transaction Transmit/Receive

 

 

1

= last BDT updated is a transmit (TX) transfer.

 

 

0

= last transaction is a receive (RX) data transfer.

2

ODD

ODD Bank of BDT

 

 

Last buffer descriptor updated is in the odd bank of the BDT.

1:0

///

Reserved

 

 

 

 

44

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Lantronix DSTni-EX USB Reset Signal, Host Mode Enable valid for host mode only, Resume Signaling, BDT PDD Reset, Reserved