Description
The GMS81C3004 is an advanced CMOS 8-bit microcontroller with 4K bytes of ROM. The device is one of GMS800 family. The LG Semicon GMS81C3004 is a powerful microcontroller which provides a highly flexible and cost effective solution to many LCD applications such as controller with LCD and toys. The GMS81C3004 provides the following standard features: 4K bytes of ROM, 256 bytes of RAM, 8-bit timer/counter, on-chip oscillator and clock circuitry. In addition, the GMS81C3004 supports power saving modes to reduce power consumption.

Features
• 4K Bytes On-chip Program Memory
• 256 Bytes of On-chip Data RAM (Included 64 bytes stack memory)
• Dot Matrix LCD Driver
    - Max. 320 dots (40 seg. x 8 com.)
    - 40 bytes of Display RAM
• Instruction Cycle Time:
    - 0.5us, 1.9us, 3.8us, 15.2us at 4.19MHz
    - 61us, 244us, 488us, 1.95ms at 32.768KHz
• 51 Programmable I/O pins (Included 32 LCD pins)
• 2.2V to 5.5V Wide Operating Range
• Dual Clock Operation (4.19MHz, 32kHz)
• One 8-bit Basic Interval Timer
• Key Scan
• One 8-bit Timer/ Counter
• Watch Timer
• Watchdog timer
• Eight Interrupt sources
    - External input: 3
    - Keyscan input: 1
    - Timer: 4
• Buzzer Driving port
    - 500Hz ~ 130kHz
• 4-channel 5-bit On-chip Comparator
• Power Down Mode
    - STOP mode
    - SLEEP mode