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NEC switch User Manual

Page 105

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CHAPTER 8 USB FUNCTION

User’s Manual U12978EJ3V0UD

105

Figure 8-7. Configuration of Transmit Data Bank 1 (Buffer 1)

Data area (8 bytes)

USBPO

W address

ID area

USBPOB address

USBTD1

Symbol

07H

06H

05H

04H

03H

02H

01H

USBT10

USBT11

USBT12

USBT13

USBT14

USBT15

USBT16

USBT17

30H

00H

31H

32H

33H

34H

35H

36H

37H

38H

The operation during transmission appears as follows.

8th byte

1st byte

USBT00

USBT07

USBT10

USBT17

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IN

DATA0

ACK

Packet from host controller

Response packet

8th byte

1st byte

USBT00

USBT07

USBT10

USBT17

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IN

DATA1

ACK

Data is read according to the data sequence in the control read data stage and is transmitted to the host. In the

DATA0 sequence, the values saved in USBT00 to USBT07 are transmitted in sequence to the host. In the

DATA1 sequence, the values saved in USBT10 to USBT17 are transmitted in sequence to the host.