Section 18 Universal Serial Bus Interface (USB)
Rev. 3.00 Jan 25, 2006 page 618 of 872
REJ09B0286-0300
18.4.5
Suspend/Resume Operation
The USB function core automatically enters a suspend state if the USB data line is placed in an
idle state for a time equal to or greater than that specified by the USB standard Rev. 1.1.
A suspend state is automatically cancelled (resumed) when the upstream (host) resumes data
transfer. A suspend state can also be forcibly cancelled (resumed) by the USB function (remote
wakeup).
Suspend state and resume state transitions can be detected by the SPNDIF and SPNDOF flags. A
SPNDOF interrupt can be accepted by waking up this LSI even if the LSI is placed in software
standby mode. In this case, the oscillator and PLL circuit must be started up according to the
startup sequence.
Whether remote wakeup is enabled or not is checked by the RWUPS flag of DEVRSMR. If
remote wakeup is enabled, remote wakeup is performed by setting the DVR bit of DEVRSMR
to 1.
18.4.6
USB Module Reset and Operation Stop Modes
The USB module can be placed in a reset state or operation stop mode by using multiple control
bits. To startup the USB module by sequentially specifying these control bits, refer to section
18.4.7, USB Module Startup Sequence.
The USB supports the following reset and operating stop states. Hardware standby and reset states
initializes the entire USB module. In each register description, initialization conditions are not
described and only initial values are shown.
1. Hardware standby mode
2. Reset state
3. Module stop mode
4. Software standby mode
5. USB bus reset state
6. USB suspend state
Hardware Standby Mode:
Hardware standby mode is entered by bringing the
STBY
pin of the
LSI to low. In hardware standby mode, registers that can be initialized and the internal status of
the LSI are initialized and all pins of the LSI are placed in a high impedance state.
XTAL-EXTAL system clock oscillation stops in the clock pulse generator.
Summary of Contents for H8S/2158
Page 10: ...Rev 3 00 Jan 25 2006 page viii of lii...
Page 36: ...Rev 3 00 Jan 25 2006 page xxxiv of lii B Product Lineup 863 C Package Dimensions 864 Index 865...
Page 47: ...Rev 3 00 Jan 25 2006 page xlv of lii Appendix Figure C 1 Package Dimensions TBP 112A 864...
Page 54: ...Rev 3 00 Jan 25 2006 page lii of lii...
Page 70: ...Section 1 Overview Rev 3 00 Jan 25 2006 page 16 of 872 REJ09B0286 0300...
Page 118: ...Section 3 MCU Operating Modes Rev 3 00 Jan 25 2006 page 64 of 872 REJ09B0286 0300...
Page 126: ...Section 4 Exception Handling Rev 3 00 Jan 25 2006 page 72 of 872 REJ09B0286 0300...
Page 198: ...Section 6 Bus Controller Rev 3 00 Jan 25 2006 page 144 of 872 REJ09B0286 0300...
Page 326: ...Section 10 8 Bit PWM Timer PWM Rev 3 00 Jan 25 2006 page 272 of 872 REJ09B0286 0300...
Page 440: ...Section 15 Watchdog Timer WDT Rev 3 00 Jan 25 2006 page 386 of 872 REJ09B0286 0300...
Page 606: ...Section 17 I 2 C Bus Interface IIC Rev 3 00 Jan 25 2006 page 552 of 872 REJ09B0286 0300...
Page 742: ...Section 19 Multimedia Card Interface MCIF Rev 3 00 Jan 25 2006 page 688 of 872 REJ09B0286 0300...
Page 750: ...Section 21 D A Converter Rev 3 00 Jan 25 2006 page 696 of 872 REJ09B0286 0300...
Page 768: ...Section 22 A D Converter Rev 3 00 Jan 25 2006 page 714 of 872 REJ09B0286 0300...
Page 770: ...Section 23 RAM Rev 3 00 Jan 25 2006 page 716 of 872 REJ09B0286 0300...
Page 824: ...Section 26 Clock Pulse Generator Rev 3 00 Jan 25 2006 page 770 of 872 REJ09B0286 0300...
Page 844: ...Section 27 Power Down Modes Rev 3 00 Jan 25 2006 page 790 of 872 REJ09B0286 0300...
Page 878: ...Section 28 List of Registers Rev 3 00 Jan 25 2006 page 824 of 872 REJ09B0286 0300...
Page 926: ...Index Rev 3 00 Jan 25 2006 page 872 of 872 REJ09B0286 0300...