SH7263 Datasheet, PDF (1354/1862 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7260 Series

Section 25 USB 2.0 Host/Function Module (USB)
2. When SOFRM = 1 is set
The SOFR interrupt is generated when SOF packets are damaged or missing. During high-
speed communication, interrupts are generated only if the first packet of a μSOF packet with
the same frame number is damaged or missing. (Corrupted or missing SOFs are recognized by
the SOF interpolation function. For details, see section 25.4.9, SOF Interpolation Function.)
When the function controller function is selected, this module updates the frame number and
generates an SOFR interrupt if it detects a new SOF packet during full-speed operation. During
high-speed operation, however, this module does not update the frame number, or generates no
SOFR interrupt until the module enters the μSOF locked state. Also, the SOF interpolation
function is not activated. The μSOF lock state is the state in which μSOF packets with different
frame numbers are received twice continuously without error occurrence.
The conditions under which the μSOF lock monitoring begins and stops are as follows.
1. Conditions under which μSOF lock monitoring begins
USBE = 1
2. Conditions under which μSOF lock monitoring stops
USBE = 0 (software reset), a USB bus reset is received, or suspended state is detected.
Peripheral Device
SOF interpolation
μSOF packet
μSOF number 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1
Frame number
3
SOFR interrupt
(SOFRM = 0)
(SOFRM = 1)
4
6
SOF interpolation function
SOF missing
μSOF lock
SOF interpolation SOF interpolation
μSOF packet
μSOF number
μSOF lock
701
67 0
70 1
SOFR interrupt
Not locked
Not locked
70 1 2
70 1
SOF interpolation,
missing
Figure 25.8 Example of SOFR Interrupt Output Timing
Rev. 2.00 Mar. 14, 2008 Page 1320 of 1824
REJ09B0290-0200