Internal Program Memory Space; Vector Table - NEC PD78081(A) User Manual

3.1.1 Internal program memory space

The internal program memory is mask ROM with a 8192
8-bit configuration in the PD78082, and PROM with a 24576
The internal program memory space stores programs and table data. Normally, they are addressed with a program
counter (PC).
The internal program memory is divided into the following three areas.
(1) Vector table area
The 64-byte area 0000H to 003FH is reserved as a vector table area. The RESET input and program start
addresses for branch upon generation of each interrupt request are stored in the vector table area. Of the
16-bit address, low-order 8 bits are stored at even addresses and high-order 8 bits are stored at odd addresses.
(2) CALLT instruction table area
The 64-byte area 0040H to 007FH can store the subroutine entry address of a 1-byte call instruction (CALLT).
(3) CALLF instruction entry area
The area 0800H to 0FFFH can perform a direct subroutine call with a 2-byte call instruction (CALLF).
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CHAPTER 3 CPU ARCHITECTURE
Table 3-1. Vector Table
Vector Table Address
0000H
0004H
0008H
000AH
000CH
0018H
001AH
001CH
0028H
002AH
002CH
003EH
8-bit configuration in the PD78081, and a 16384
8-bit configuration in the PD78P083.
Interrupt Request
RESET input
INTWDT
INTP1
INTP2
INTP3
INTSER
INTSR/INTCSI2
INTST
INTAD
INTTM5
INTTM6
BRK