E2E0041-18-95
¡ Semiconductor
MSM63P238
¡ Semiconductor
This version: Sep. 1998
MSM63P238
4-Bit Microcontroller with Built-in 16K Word PROM, POCSAG Decoder, and Melody
Circuit
GENERAL DESCRIPTION
The MSM63P238 is a CMOS 4-bit microcontroller with a built-in POCSAG (Post Office Code
Standardization Advisory Group) decoder, which employs Oki's original nX-4/250 CPU core.
The MSM63P238 is a one-time-programmable ROM-version product having one-time PROM
(OTP) as internal program memory.
The specifications of the MSM63P238 are equal to those of the MSM63238 except for electrical
characteristics, packaging (only 80-pin flat package is available for the MSM63P238), and some
functions.
FEATURES
The features of the MSM63P238 with an asterisk (*) differ from those of the mask ROM-version
MSM63238.
• Rich instruction set
439 instructions
Transfer, rotate, increment/decrement, arithmetic operations, comparison, logic operations,
mask operations, bit operations, ROM table reference, external memory transfer, stack
operations, flag operations, branch, conditional branch, call/return, control.
• Rich selection of addressing modes
Indirect addressing of four data memory types, with current bank register, extra bank
register, HL register and XY register.
Data memory bank internal direct addressing mode.
• Processing speed
Two clocks per machine cycle, with most instructions executed in one machine cycle.
Minimum instruction execution time : 61
ms
(@ 32.768 kHz system clock)
1
ms
(@ 2 MHz system clock)
• Clock generation circuit
Low-speed clock
High-speed clock
: 32.768 kHz/38.4 kHz/76.8 kHz crystal oscillator
: 2 MHz (Max.) RC or ceramic oscillator select
• Program memory (PROM) space*
16K words
Basic instruction length is 16 bits/1 word
• Data memory space
1K nibbles
• External data memory space
64 Kbytes (expandable by using an I/O port)
1/28
OKI [ OKI ELECTRONIC COMPONETS ]
