MOS INTEGRATED CIRCUIT
16-/8-Bit Single-Chip Microcomputers
The µPD78P324 is a product in which the µPD78324’s internal mask ROM is replaced by a one-time PROM
or EPROM. The one-time PROM product, which enables writing only once, is effective for multiple-device
small production of sets or early start of mass-production. The EPROM product, which enables program
writing, deletion, and rewriting, is the most suitable for system evaluation.
The µPD78P324(A) is more reliable than the µPD78P324. The µPD78P324(A) is a product resulting from
the µPD78324(A) whose internal mask ROM is replaced by a one-time PROM.
For details of functions, please refer to the following User’s Manual. Reading this manual is indispensable
especially for designing work.
µPD78322 User’s Manual: IEU-1248
q µPD78324 compatible
• For mass-production, this can be replaced by the µPD78324 incorporated in the mask ROM.
q Minimum instruction run time: 250 ns (with the external clock operating at 16 MHz): µPD78P324 & 78P324(A)
320 ns (with the external clock operating at 12.5 MHz): µPD78P324(A1) &
q Internal PROM: 32768 x 8 bits
• Writing enabled only once (windowless one-time PROM product)
• Elimination by ultraviolet light and electrical rewriting enabled (EPROM product with window): µPD78P324
q ECC circuit incorporated
• High internal PROM content reliablility possible
q PROM programming characteristic: µPD27C1001A compatible
q QTOPTM microcomputer compatible
Remark A QTOP microcomputer is a single-chip microcomputer with one-time PROM for which program
writing, marking, screening, and verifying is completely supported by NEC.
q µPD78P324: Fields dealing with motor control equipment.
q µPD78P324(A), 78P324(A1), and 78P324(A2): Automotive and transportation equipments, etc.
This document describes the µPD78P324, 78P324(A), µPD78P324(A1), and µPD78P324(A2) as well. However,
unless there are particular differences, the µPD78P324 is described as a representative product. PROM is
the representative term used for the part common to both the one-time PROM product and the EPROM
Document No. IC-2857
(O. D. No. IC-8315)
Date Published January 1995 P
Printed in Japan
The information in this document is subject to change without notice.