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3874 Group User’s Manual
HARDWARE
FUNCTIONAL DESCRIPTION SUPPLEMENT
Interrupt
3874 group permits interrupts on the basis of 27 sources. The inter-
rupt control circuit consists of “one factor/one vector interrupt” and
“multiple factors/one vector interrupt.”
It is vector interrupts with a fixed priority system. Accordingly, when
two or more interrupt requests occur during the same sampling, the
higher-priority interrupt is accepted first. This priority is determined
Vector addresses (Note 1)
FFFD16
FFFB16
FFF916
FFF716
FFF516
FFF316
FFF116
FFEF16
FFED16
FFEB16
FFE916
FFE716
FFE516
FFE316
FFE116
FFDF16
FFDD16
FFFC16
FFFA16
FFF816
FFF616
FFF416
FFF216
FFF016
FFEE16
FFEC16
FFEA16
FFE816
FFE616
FFE416
FFE216
FFE016
FFDE16
FFDC16
Table 11 Interrupt sources, vector addresses and interrupt priority
Non-maskable
External interrupt (active edge selectable)
The condition which the receive bus interrupt
factor request bit becomes “1” is defined
according to each communication protocol
specification confirmation.
The condition which the transmit bus interrupt
factor request bit becomes “1” is defined
according to each communication protocol
specification confirmation.
External interrupt (active edge selectable)
Valid only when serial I/O3 is selected
External interrupt (active edge selectable)
Valid only when ADT interrupt is selected
External interrupt (falling valid)
Valid when A-D converter interrupt is selected
Valid only when serial I/O2 is selected
External interrupt (falling valid)
Valid only when serial I/O1 is selected
Non-maskable software interrupt
High-order
Low-order
Interrupt sources
Reset (Note 2)
INT0
INT1
Receive bus interrupt source 1
Receive bus interrupt source 2
Receive bus interrupt source 3
Transmit bus interrupt source 1
Transmit bus interrupt source 2
Transmit bus interrupt source 3
Timer X
Timer Y
Timer 2
Timer 3
INT2
Serial I/O3
CNTR0
CNTR1
Timer 1
INT3
INT4
INT5
ADT
A-D converter
Serial I/O2
Key input (key-on wake-up)
Serial I/O1 receive
Serial I/O1 transmit
BRK instruction
Priority
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
FUNCTIONAL DESCRIPTION SUPPLEMENT
Remarks
by hardware, but various priority processing can be performed by
software, using an interrupt enable bit and an interrupt disable flag.
For “multiple factors/one vector interrupt,” the priority in the same
vector can be controlled freely by software, referring an interrupt re-
quest bit.
For interrupt sources, vector addresses and interrupt priority, refer to
Table 11.
Notes 1: Vector addresses contain interrupt jump destination addresses.
2: Reset functions in the same way as an interrupt with the highest priority.
3: Either ADT interrupt or A-D converter interrupt can be used. Both ADT interrupt and A-D converter interrupt cannot be used.