HIGH PERFORMANCE KEYBOARD MICROCONTROLLER

The 83C51KB is a highly integrated keyboard microcontroller for the standard and advanced desktop keyboard industry. The integration of external components into the microcontroller reduces overall keyboard control system manufacturing cost in terms of the number of components used, the amount of PCB space required, reduced inventory, and a reduction in required assembly activities. In addition, the integration reduces the number and amount of software routines needed for signal debounce and input status poll operation. There is a resultant reduction in CPU overhead as well as on-chip memory requirements. The 83C51KB product line is manufactured with Intel state of the art complimentary high-performance metallic oxide semiconductor (CHMOS) design rules.

■ Direct Drive LED Outputs
   — Four Pins (P3.7:4)
   — 13 mA Typical Current Sink Capability
■ 20 pF Cap On-chip for RC Resonator
   — Frequency Selectable (4-6 MHz)
■ 8 Dedicated Key Scan Input (KSI) Pins
   — Schmitt-trigger Inputs
   — External Interrupt
   — Level Detect Interrupt Mode for Automatic Power-down Exit
■ 16 Dedicated Key Scan Output (KSO) Pins with Quasi-bidirectional Port Drivers
   — No External Resistor Required
   — Located on P0.7:0 and P2.7:0
■ 4-Kbyte On-chip ROM Memory
■ 128-byte On-chip RAM Memory
■ Clock/Data Drivers to Motherboard
   — Strong Pullup Drivers for Keyboard Cable Communication
   — 8X42 Compatible Interface
   — Selectable external interrupt for Clock
■ ONCE mode (On-chip Emulation)
■ Power-on Reset Mode
   — Automatic Operation
■ 5 Volt D.C. Operation
■ Reduces Manufacturing Cost by Reducing Overall Component Count
■ Configurable Timer (16 bit or 2 by 8 Bit)
■ Uses Industry Standard Design Tools
■ Control Oriented Instruction Set
■ Industry Standard Architecture