EM78M611E

Universal Serial Bus Series Microcontroller

RF [2] USB Suspend interrupt flag. It will be set when the EM78M611E finds the USB Suspend Signal on USB bus. This bit is cleared by the firmware.

RF [3] USB Reset interrupt flag. It will be set when the host issues the USB Reset signal.

RF [4] P74/P75/P76/P77 Port state change interrupt flag.

In PS2 Mode, only pins configured as inputs can cause this interrupt to occur. These pins (P74, P75, P76 and P77) are compared with the value latched on the last read of Port 7.

In USB Mode, P76 and P77 have this function.

NOTE

R F[4]: Port State Change Interrupt Flag,

EM78M611

USB Mode –P76 and P77 DO NOT have interrupt function.

PS2 Mode – P74/P75/P76/P77 have interrupt function.

EM78M611E

P74/P75/P76/P77 all have interrupt function (in USB & PS2 mode)

RF [5, 6] SE1 / SE2 Pattern Detect Interrupt flag. These two flags are used for Pattern detect application.

RF [7] USB Host Resume interrupt flag. It will be set only in Dual clock mode when the USB suspend signal becomes low.

NOTE

RF [7]: USB Host Resume_IF

In EM78M611, this bit is always ‘1’. It is not for use.

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

8.2.3 Control Registers

Some special purpose registers are available for special control purposes. Except for the Accumulator (ACC), these registers must be read and written with special instructions. One of these registers, CONT, can only be read by the instruction "CONTR" and written by "CONTW" instruction. The other special control registers can be read by the instruction "IOR" and written by the instruction "IOW".

The following paragraphs describe only the general functions of the control registers.

8.2.3.1A (Accumulator)

The accumulator is an 8-bit register that holds operands and results of arithmetic calculations. It is not addressable. After an interrupt occurs, the Accumulator is auto-saved by hardware.

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Product Specification (V1.1) 11.22.2006

(This specification is subject to change without further notice)

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IBM EM78M611E manual Control Registers, Accumulator