Preliminary W77E468
GENERAL DESCRIPTION
The W77E468 is a fast 8051 compatible microcontroller with a redesigned processor core without
wasted clock and memory cycles. As a result, it executes every 8051 instruction faster than the
original 8051 for the same crystal speed. Typically, the instruction executing time of W77E468 is 1.5
to 3 times faster then that of traditional 8051, depending on the type of instruction. In general, the
overall performance is about 2.5 times better than the original for the same crystal speed. Giving the
same throughput with lower clock speed, power consumption has been improved. Consequently, the
W77E468 is a fully static CMOS design; it can also be operated at a lower crystal clock. The
W77E468 contains 32KB flash Multiple-Time Programmable(MTP) ROM, and provides the separate
address and data bus that does not require an external latch device for multiplexing low byte
addresses. The W77E468 also support on-chip 1KB SRAM without external memory component and
glue logic, saving more I/O pins for users application usage if they use on-chip SRAM instead of
external SRAM.
FEATURES
• 8-bit CMOS microcontroller
• High speed architecture of 4 clocks/machine cycle runs up to 40 MHz
• Pin compatible with standard 80C52
• Instruction-set compatible with MCS-51
• Six 8-bit I/O Ports and one 4-bit I/O Port
• Three 16-bit Timers
• 12 interrupt sources with two levels of priority
• On-chip oscillator and clock circuitry
• Two enhanced full duplex serial ports
• 32 KB flash Multiple-Time Programmable(MTP) ROM
• 256 bytes scratch-pad RAM
• 1 KB on-chip SRAM for MOVX instruction
• Programmable Watchdog Timer
• Dual 16-bit Data Pointers
• Hardware/Software optional variable access cycle to external RAM/peripherals
• Packages:
− QFP 100: W77E468F-25/40
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