ISP1122A Просмотр технического описания (PDF) - Philips Electronics

Номер в каталоге

Компоненты Описание

производитель

ISP1122A

Universal Serial Bus stand-alone hub

Philips Electronics 

Philips Semiconductors

ISP1122A

USB stand-alone hub

10.2 Hardware connections

Via the I2C-bus interface the ISP1122A can be connected to an external EEPROM

(PCF8582 or equivalent). The hardware connections are shown in Figure 5.

The SCL and SDA pins are multiplexed with pins OPTION and INDV respectively.

idth

VDD

VDD

OPTION/SCL

INDV/SDA

ISP1122A

USB HUB

RP

RP

I2C-bus

SCL

A0

SDA

A1

PCF8582 A2

EEPROM

or

equivalent

Fig 5. EEPROM connection diagram.

MBL166

The slave address which ISP1122A uses to access the EEPROM is 1010000B. Page

mode addressing is not supported, so pins A0, A1 and A2 of the EEPROM must be

connected to GND (logic 0).

10.3 Data transfer

When the ISP1122A is reset, the I2C-bus interface tries to read 6 bytes of

configuration data from an external EEPROM. If no response is detected, the levels

on inputs SDA and SCL are interpreted as INDV and OPTION to select the operating

mode (see Table 4).

The data in the EEPROM memory are organized as shown in Table 22.

Table 22: EEPROM organization

Address

(Hex)

Default value

(Hex)

00

CC

01

04

02

22

03

11

04

-

05

AA

Contents

idVendor [1] (lower byte)

idVendor [1] (upper byte)

idProduct [2] (lower byte)

idProduct [2] (upper byte)

configuration bits C7 to C0; see Table 23

signature

[1] Vendor ID code in the Device descriptor, see Table 10.

[2] Product ID code in the Device descriptor, see Table 10.

9397 750 06986

Preliminary specification

Rev. 01 — 27 March 2000

© Philips Electronics N.V. 2000. All rights reserved.

21 of 48

Share Link: