1.0 General Description
The ASM3112C/4112C is very low cost voice synthesizer with 4-bit microprocessor. It has various
features including 4-bit ALU, ROM, RAM, I/O ports, timers, clock generator, watchdog timer(WDT)
voice synthesizer, etc. It consists of 22 instructions in the device. With CMOS technology and halt
function can minimize power dissipation. Its architecture is similar to RISC, with two stages of
instruction pipeline. It allows all instructions to be executed in a single cycle, except for program
branches and data table read instructions (which need two instruction cycles).

1.1 Feature
Single power supply can operate from 2.4V through 5.5V
Internal Program ROM: 4K x 10-bit
1 sets of 17-bit DPR can access up to 128K x 10 bits data memory space
Data Registers:
   • 96 x 4-bit data RAM (00-1Fh plus 40h-7Fh)
   • Unbanked special function registers (SFR) range: 20h-3Fh
I/O Ports:
   • PRA: 4-bit I/O Port A (2Bh)
   • PRB: 4-bit Output Port B (2Dh)
   • PRC: 4-bit Input Port C (2Fh)
On-chip clock generator: Resistive Clock Drive(RM)
Timer: 1
   • Timer0: a 9-bit auto-reload timer/counter
Stack: 2-level subroutine nesting
HALT and Release from HALT function to reduce power consumption
Watch Dog Timer (WDT)
Instruction: 1-cycle instruction except for table read and program branches which are 2-cycles
Number of instruction: 22
The Voice function can be implemented by microprocessor instruction
   • One 8-bit COUT output for ASM3112C/4112C