80C51 1Header

TK8xC51Rx2 Microcontroller

TK80C51RA2 – ROMLess 
TK83C51RB2 – 8K Masked ROM
TK87C51RA2 – 8K Flash
TK87C51RB2 – 16K Flash
TK87C51RC2 – 32K Flash
TK87C51RD2 – 64K Flash

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  • 8 Bit Microcomputer with 8051 architecture
  • Fully static design
  • 256B internal RAM + 256 bytes XRAM
  • Up to 64K Flash ROM
  • Low Standby Current At Full Supply Voltage
  • 0-33 MHz Operation (12 clock mode)
  • 4 8-Bit Bidirectional Ports
  • Boolean Processor
  • Built In Power Management
  • Three 16 bit timer/counters
  • Full Duplex Serial Channel With Hardware Address Decode
  • Seven Source, Four Level Interrupt Capability
  • Programmable Counter Array
  • Watchdog Timer For Greater System Reliability
  • Dual Data Pointers
  • 6 clock / 12 clock select
  • Three Package Options:
    • PLCC - (A)
    • PDIP - (P)
    • LQFP - (B)
  • Replaces Comparable devices from:
    • Intel
    • NXP
    • Atmel
  • Six Memory Options
    • TK80C51RA2 - ROMless
    • TK83C51RA2 – 8K ROM
    • TK87C51RA2 – 8K Flash
    • TK87C51RB2 – 16K Flash
    • TK87C51RC2 – 32K Flash
    • TK87C51RD2 – 64K Flash

General Description

The new Tekmos 8xC51Rx2 microcontroller is designed to replace all of the ROMless, ROM, and One-Time-Programmable (OTP) members of the 8051 family. In addition, since Tekmos uses Flash instead of EPROM, the Tekmos devices are re-programmable.

The TK8xC51Rx2 is based on the 8051- microcontroller architecture. The ROMless version is a pin-for-pin replacement for existing 8031BH, 8032-1, 80C32X2, and 80C51FA type microcontroller from Intel, NXP, Atmel and others. The Flash version serves as a replacement for the 87C51RA2, 87C51RB2, 87C51RC2, and 87C51RD2 microcontrollers. The flash version can also serve as a replacement for many of the 89C51Rx2 devices. The TK8xC51Rx2 is also available in a masked ROM version.

The TK8xC51Rx2 contains four 8-bit bidirectional parallel ports, two external interrupt sources, three timer/counters, a serial port with a hardware interrupt capability and a frame error detect flag, power management, and a programmable counter array (PCA). These peripherals are supported by a multiple source, four level interrupt capability. The core processor contains 256 bytes of scratchpad RAM along with another 256 bytes of XRAM. Program storage is 8K, 16K, 32K, or 64Kbytes in size.

The use of the original instruction timing insures that the original code will continue to perform correctly while running in the Tekmos design. The performance advantages resulting from the 0.35u process allow the Tekmos part to replace all of the earlier version's speed grades. The use of a current process also insures the long term availability of this part.


Feature Tekmos 80C31BH 80C32-1 80C51FA 80C32X2
RAM (Bytes) 256 128 256 256 256
Interrupts 7 5 6 7 6
Interrupt Priority Levels 4 2 2 4 4
Data Pointers 2 1 1 1 or 2 2
UART - Basic Yes Yes Yes Yes Yes
Timer 0 & 1 Yes Yes Yes Yes Yes
Timer 2 - Basic Yes No Yes Yes Yes
Timer 2 - Enhanced Yes No No Yes Yes
UART - Enhanced Yes No No Yes Yes
PCA Yes No No Yes No
POF (Power Off Flag) Yes No No Yes Yes
X2 Clock Control Yes No No No Yes
Hardware Watchdog Yes No No No No


The data sheet is available here: pdf TK8xC51Rx2 (416 KB)

Product Change Notice Form:  pdf PCN 17004 (307 KB)  

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