UPD78F9500MA-CAC-A Datasheet, PDF (178/342 Pages) Renesas Technology Corp – 8-Bit Single-Chip Microcontrollers

CHAPTER 10 INTERRUPT FUNCTIONS
10.1 Interrupt Function Types
There are two types of interrupts: maskable interrupts and resets.
• Maskable interrupts
These interrupts undergo mask control. When an interrupt request occurs, the standby release signal occurs,
and if an interrupt can be acknowledged then the program corresponding to the address written in the vector
table address is executed (vector interrupt servicing). When several interrupt requests are generated at the
same time, processing takes place in the priority order of the vector interrupt servicing. For details on the
priority order, see Table 10-1.
There are internal sources and external sources of maskable interrupts.
• μPD78F920x: external sources: 2, internal sources: 5
<R>
• μPD78F950x: external sources: 2, internal sources: 2
• Reset
The CPU and SFR are returned to their initial states by the reset signal. The causes for reset signal
occurrences are shown in Table 10-1.
When a reset signal occurs, program execution starts from the programs at the addresses written in addresses
0000H and 0001H.
10.2 Interrupt Sources and Configuration
<R> There are a total of seven maskable interrupt sources in μPD78F920x, and four maskable interrupt sources in
μPD78F950x, and up to four reset sources (see Table 10-1).
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User’s Manual U18172EJ3V0UD