MC908JB16DWE Datasheet, PDF (203/332 Pages) Freescale Semiconductor, Inc – Microcontrollers

Universal Serial Bus Module (USB)
SETUP transactions cannot be stalled by the USB function. A SETUP
received by a control endpoint will clear the ISTALL0 and OSTALL0 bits.
The conditions for receiving a SETUP interrupt are shown in
Figure 11-30.
VALID SETUP TOKEN
RECEIVED FOR ENDPOINT 0?
Y
USB MODULE ENABLED?
N
(USBEN = 1)
Y
ENDPOINT 0 RECEIVE READY TO RECEIVE? N
(RX0E = 1) AND (RXD0F = 0)
Y
NO RESPONSE
FROM USB FUNCTION
NO RESPONSE
FROM USB FUNCTION
ACCEPT DATA
SET/CLEAR R0SEQ BIT
SET SETUP BIT TO 1
ERROR FREE DATA PACKET?
N
Y
SET RXD0F TO 1
IGNORE TRANSACTION
NO RESPONSE FROM
USB FUNCTION
RECEIVE CONTROL ENDPOINT
N
INTERRUPT ENABLED?
(RXD0IE = 1)
Y
VALID TRANSACTION
INTERRUPT GENERATED
NO INTERRUPT
Figure 11-30. SETUP Token Data Flow for Receive Endpoint 0
MC68HC908JB16 — Rev. 1.1
Freescale Semiconductor
Universal Serial Bus Module (USB)
Technical Data
203