SH7670 Datasheet, PDF (785/1292 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7670 Series

Section 17 USB 2.0 Host/Function Module (USB)
Changing the HSE bit should be done between the ATTCH interrupt detection and bus reset
execution when the host controller function is selected, or with the D+ line pull-up disabled
(DPRPU = 0) when the host controller function is selected.
(4) USB Data Bus Resistor Control
Figure 17.1 shows a diagram of the connections between this module and the USB connectors.
This module incorporates a pull-up resistor for the D+ signal and a pull-down resistor for the D+
and D- signals. These signals can be pulled up or down using the DPRPU and DRPD bits in
SYSCFG.
This module controls the terminal resistor for the D+ and D- signals during high-speed operation
and the output resistor for the signals during full-speed operation. This module automatically
switches the resistor after connection with the host controller or peripheral device by means of
reset handshake, suspended state and resume detection.
When the function controller function is selected and the DPRPU bit in SYSCFG is cleared to 0
during communication with the host controller, the pull-up resistor (or the terminal resistor) of the
USB data line is disabled, making it possible to notify the USB host of the device disconnection.
Rev. 1.00 Nov. 14, 2007 Page 759 of 1262
REJ09B0437-0100