Usb Interface - Renesas M3A-HS85 User Manual

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2.7 USB Interface

The M3A-HS85 contains a USB connector (Standard-B receptacle).
When a cable is connected to USB host/hub in the state that this CPU board is not turned on, the voltage is
impressed from USB host/hub to VBUS. Thus, the CPU board should be turned on before USB cable is connected.
When you want to delay a notification of connection to USB host/hub (the cases such as in the processing of high
priority or initialization), it can be controlled by PB10. The powered state is kept regardless of the states USD+ and
USD- when pin VBUS of SH7285 is set to low level.
Figure 2.7.1 shows the block diagram of M3A-HS85 USB interface.
Oscillator (48MHz)
Ceralock
CSTCZ48M0X12R
(Murata)
Rev.1.04 2008.7.10
REJ10J1564-0104
3.3V
SH7285
DrVCC
DrVSS
USBEXTAL
USBXTAL
：Not mounted
Figure 2.7.1 Block Diagram of USB Interface
PB10
HD74LV1GT08ACME-E
VBUS
HD74LV1GT126ACME-E
3.3V
OE
USD+
USD-
Vbus PB10 VBUS D+
0 0 0 Hi-Z
0 1 0 Hi-Z
1 0 0 Hi-Z
1
1 1 Pull-up
Functional Overview
2.7 USB Interface
USB
series B
connector
Vbus
D+
D-
GND
Remarks
Initial value
When USB is connected
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