Tandy 1000 HX Technical Reference Manual page 166

SEC
NEC Electronics Inc.
A/PD8035HL/48H
HIGH-SPEED, 8-BIT, SINGLE-CHIP
HMOS MICROCOMPUTERS
Description
The
M
PD8035HL and the
M
PD8048H make up the
fiPD8048H family of single-chip 8-bit microcomputers.
The processors in this family differ only in their internal
program memory options: the /iPD8048H with 1Kx8
bytes of mask ROM and the MPD8035HL with external
memory.
The NEC /-(PD8035HL and nPD8048H are single
component, 8-bit, parallel microprocessors using
n-channel silicon gate MOS technology. The *iPD8048H
family of components functions efficiently in control as
well as in arithmetic applications. Standard logic
function implementation is facilitated by the large
variety of branch and table look-up instructions.
The A<PD8035HL/48H instruction set comprises 1
and 2 byte instructions with over 70% of them
single-byte. Execution requires only 1 or 2 cycles per
instruction and over 50% are single-cycle instructions.
The functions of the jiPD8048H series of micro-
processors can easily be expanded using standard
8080A/8085A peripherals and memories.
The/iPD8048M contains the following functions usually
found in external peripheral devices: 1024x8 bits of
ROM program memory; 64x8 bits of RAM data
memory; 27 I/O lines; an 8-bit interval timer/event
counter; oscillator and clock circuitry.
The
M
PD8035HL is intended for applications using
external program memory only. It contains all the
features of the /iPD8048H except the 1024 x 8-bit
internal ROM. The external program memory can be
implemented using standard 8080A/8085A memory
products.
Features
• Fully compatible with industry standard
8048/8748/8035
D 2.5 MS cycle time: all instructions 1 or 2 bytes
• Interval timer/event counter
D 64 x 8-byte RAM data memory
• External and timer interrupts
• 96 instructions: 70% single byte
• 27 I/O lines
D Internal clock generator
D 8 level stack
D Compatible with 8080A/8085A peripherals
• HMOS silicon gate technology
• Single+5 V power supply
Ordering Information
Part
Number
//PD8035HLC
//PD8048HC
Package Type
40-pin plastic DIP
40-pin plastic DIP
Max Frequency
of Operation
6 MHz
6 MHz
Pin Configuration
Pin Identification
No.
1
2
3
4
5
6
7
8
9
10
11
12-19
20
21-24, 35-38
25
Symbol
T O
XTAL1
XTAL2
RESET
SS
T N T
E A
R D
PSEN
W R
ALE
DB
0
-DB
7
Vss
P2
0
-P2
7
PROG
Function
Test 0 input /output
Crystal 1 input
Crystal 2 input
Reset input
Single step input
Interrupt input
External access input
Read output
Program store enable output
Write output
Address latch enable output
Bidirectional data bus
Ground
Quasi-bidirectional Port 2
Program output
4-201