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CHAPTER 6 INTERRUPTS
MB90560 series
6.1
Interrupts
This chapter explains the interrupts and extended intelligent I/O service (EI
2
OS) in the
MB90560 series.
Hardware interrupts
Software interrupts
Interrupts from extended intelligent I/O service (EI
2
OS)
Exception processing
I
Interrupt types and functions
G
Hardware interrupt
A hardware interrupt transfers control to a user-defined interrupt processing program in response
to an interrupt request from a peripheral function.
G
Software interrupt
A software interrupt transfers control to a user-defined interrupt processing program triggered by
the execution of a dedicated software interrupt instruction (such as the INT instruction).
G
Interrupt from extended intelligent I/O service (EI
2
OS)
The EI
2
OS function automatically transfers data between a peripheral function and memory.
Data transfer, which has ordinarily been executed by an interrupt processing program, can be
handled like a direct memory access (DMA). When the specified number of data transfers has
been terminated, the interrupt processing program is automatically executed.
An instruction from EI
2
OS is a type of hardware interrupt.
G
Exception processing
Exception processing is basically the same as an interrupt. When an exception event (execution
of an undefined instruction) is detected on the instruction boundary, ordinary processing is
interrupted and exception processing is performed. This is equivalent to software interrupt
instruction INT10.