IBM EM78M611E manual PU8 PU6 PU5

EM78M611E

Universal Serial Bus Series Microcontroller

8.2.3.8IOCE (Special Function Control Register) Default Value: (0B_1101_0111)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
/Dual clock	/WUE	WTE	RUN	Device_Resume	/PU8	/PU6	/PU5

IOCE [0, 1, 2] Port 5, Port 6, and Port 8 pull-high control bits. 0 : Enable

1 : Disable

IOCE [3] Setting this bit will allow the UDC to execute resume signaling. This bit is set by firmware to generate a signal to wake-up the USB host and is cleared as soon as the USB Suspend signal becomes low. It can only be used in Dual clock mode when the USB suspend signal becomes low.

NOTE

IOCE[3]: Device_Resume bit

In EM78M611, this bit is always ‘0’. It is not for use.

In EM78M611E, this bit is O.K. for use.

IOCE [4] Run bit. This bit can be cleared by firmware and set during power-on, or by the hardware at a falling edge of the wake-up signal. When this bit is cleared, the clock system is disabled and the MCU enters into Power down mode. At the transition of wake-up signal from high to low, this bit is set to enable the clock system.

0 : Sleep mode. The EM78M611E is in power down mode.

1 : Run mode. The EM78M611E is working normally.

IOCE [5] Watchdog Timer enable bit. The bit disables/enables the Watchdog Timer.

0 : Disable WDT

1 : Enable WDT

IOCE [6] Enable the wake-up function as triggered by port-changed. This bit is set by UDC.

0 : Enable the wake-up function

1 : Disable the wake-up function

IOCE [7] Dual clock Control bit. This bit is used to select the frequency of system clock. When this bit is cleared, the MCU will run on very low frequency for power saving and the UDC will stop working.

0 : Selects to run on slow frequency

1 : Selects EM78M611E to run on normal frequency

20 • Product Specification (V1.1) 11.22.2006

(This specification is subject to change without further notice)