Internal Program Memory Space - NEC 78014Y Series User Manual

8-bit single-chip microcontrollers

Table of Contents

5.1.1 Internal program memory space

Internal program memory store programs and table data. Normally, they are addressed with a program counter

The µ PD78014 and 78014Y Subseries contain internal ROM (or PROM) in each product having the capacities

shown below.

The following areas are allocated in the internal program memory space.

(1) Vector table area

The 64-byte area 0000H to 003FH is reserved as 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, the low-order 8 bits are stored at even addresses and the high-order 8 bits are stored at odd

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Vector Table Address

(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).

CHAPTER 5 CPU ARCHITECTURE

Table 5-1. Internal ROM Capacity

Configuration

µ PD78011B, 78011BY

µ PD78012B, 78012BY

µ PD78013, 78013Y

µ PD78014, 78014Y

µ PD78P014, 78P014Y

Table 5-2. Vector Table

Interrupt Source

Internal ROM

8192 × 8 bits

16384 × 8 bits

24576 × 8 bits

32768 × 8 bits

Vector Table Address

Interrupt Source

BRK Instruction