NEC PD750008 - Manual (Page 203)

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CHAPTER 6 INTERRUPT AND TEST FUNCTIONS
CHAPTER 6 INTERRUPT AND TEST FUNCTIONS
The µPD750008 has seven vectored interrupt sources and two test inputs, allowing a wide range of
applications.
In addition, the interrupt control circuitry of the µPD750008 has the following features for very high-speed
interrupt processing.
(1) Interrupt functions
(a) Hardware controlled vectored interrupt function which can control whether or not to accept an interrupt
using the interrupt flag (IExxx) and interrupt master enable flag (IME).
(b) The interrupt start address can be set arbitrarily.
(c) Multiple interrupt function which can specify the priority by the interrupt priority specification register
(IPS)
(d) Test function of an interrupt request flag (IRQxxx)
(The software can confirm that an interrupt occurred.)
(e) Release of the standby mode (Interrupts released by an interrupt enable flag can be selected.)
(2) Test functions
(a) Whether test request flags (IRQxxx) are issued can be checked with software.
(b) Release of the standby mode (A test source to be released can be selected with test enable flags.)
6.1 CONFIGURATION OF THE INTERRUPT CONTROL CIRCUIT
Figure 6-1 shows the configuration of the interrupt control circuit. Each hardware item is mapped to a data
memory space.
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