Cypress EZ-USB FX3 User Manual

EZ-USB FX3 Technical Reference Manual, Document Number: 001-76074 Rev. *F 397
DEV_TOGGLE
0xE0031414
10.11.5 DEV_TOGGLE
Data Toggle for Endpoints Register
Data toggles when all endpoints reset to ‘0’, on power-up, or on USB reset. In general, hardware maintains all the data toggle
bits, which are toggled between data packet transfers. The firmware might need to reset or set data toggle bit only following
conditions:
■ After a configuration changes (i.e., after the host issues a Set Configuration request).
■ After an interface’s alternate setting changes (i.e., after the host issues a Set Interface request).
■ After the host sends a Clear Feature - Endpoint Stall request to an endpoint.
To change the value of the toggle bit, software must first write ENDPOINT and IO, then poll for TOGGLE_VALID=1, then write
to R/S, then poll again for TOGGLE_VALID=1.
8 TOGGLE_VALID Indicates Q is valid for selected endpoint, may be polled in software.
After writing to R/S, indicates write completion.
This bit must be cleared by software to initiate an operation.
7Q Current value of toggle bit for EP selected in IO/ENDPOINT
6S Write ‘1’ to set data toggle to ‘1’. When both R and S are set, behavior is undefined.
5R Write ‘1’ to reset data toggle to ‘0’. When both R and S are set, behavior is undefined.
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DEV_TOGGLE Data Toggle for Endpoints Register 0xE0031414
b31 b30 b29 b28 b27 b26 b25 b24
DEV_TOGGLE Data Toggle for Endpoints Register
b23 b22 b21 b20 b19 b18 b17 b16
DEV_TOGGLE Data Toggle for Endpoints Register
b15 b14 b13 b12 b11 b10 b9 b8
TOGGLE_VALID
R/W0C
R/W1S
1
DEV_TOGGLE Data Toggle for Endpoints Register
b7 b6 b5 b4 b3 b2 b1 b0
Q S R IO ENDPOINT[3:0]
R R/W R/W R/W R/W R/W R/W R/W
R/WRRRRRRR
00000000
Bit Name Description

Cypress EZ-USB FX3 Specifications

General

Brand	Cypress
Model	EZ-USB FX3
Category	Controller
Language	English