ST5481

10/18

If Pin CFG1 is 1, when reset (PON,USB,PIN) is active the initial state is INACTIVE.

9 - ENDPOINTS CONFIGURATION AND DEDICATION

These endpoints are organized as one interface

(interface 0), one configuration (configuration 1).

The interface being composed of four alternate

settings. Hereafter in the document RX data

direction is from S line to PC and is considered as

IN by USB protocol.

The endpoints are:

– 4 isochronous endpoints for B1 and B2 channels

(fifo 32 bytes in each direction)

line

- associated to IN(RX) fifo 32 bytes

on S line

- associated to OUT(TX) fifo 32 bytes

line

- associated to IN(RX) fifo 32 bytes

on S line

- associated to OUT(TX) fifo 32 bytes

– 2 isochronous endpoints for D channels (fifo 16

bytes in each direction)

line

- associated to IN(RX) fifo 16 bytes

S line

- associated to OUT(TX) fifo 16 bytes

– 1 control endpoint means management of USB

standards, Communication Device Class (CDC)

standards (unused), and vendor requests (S in-

terface application dedicated):

- internal configuration and control registers

- D, B1, B2 channels transmit commands

- CI primitives to be transmitted

– 1 interrupt endpoint used for vendor interrupts

- channels reception or transmission indications

- CI primitives in receive direction

- D, B1, B2 channel reception indications

- S line status

- GPIO input changes

The alternate settings are:

- initialisation configuration

- connection 64Kbits through B1 channel

- connection 64Kbits through B2 channel

EP5, EP6, EP7

- connection 128Kbps (144Kbits/sec) through

B1 + B2 + (data into D) channels

Figure 7 : S Interface States - CFG1=1

OFF

PON RESET /

USB REQUEST/

PIN RESET

M3

M2

STT(5)=0

STT(5)=1

PDN or PDWN=1

PUP or NLSD=0

STT(5)=1

M1 OFF

S LINE ACTIVATION

NOT POSSIBLE

ACTIVE

INACTIVE S LINE ACTIVATION

POSSIBLE