Preliminary W78C51D 8-BIT MICROCONTROLLER
GENERAL DESCRIPTION
The W78C51D microcontroller supplies a wider frequency and supply voltage range than most 8-bit microcontrollers on the market. It is compatible with the industry standard 80C51 microcontroller series. The W78C51D contains four 8-bit bidirectional parallel ports, one extra 4-bit bit-addressable I/O port (Port 4) and two additional external interrupts ( INT2 , INT3 ), two 16-bit timer/counters, one watchdog timer and a serial port. These peripherals are supported by a seven-source, two-level interrupt capability. There are 128 bytes of RAM and an 4K byte mask ROM for application programs. The W78C51D microcontroller has two power reduction modes, idle mode and power-down mode, both of which are software selectable. The idle mode turns off the processor clock but allows for continued peripheral operation. The power-down mode stops the crystal oscillator for minimum power consumption. The external clock can be stopped at any time and in any state without affecting the processor.
FEATURES
• Fully static design • Supply voltage of 4. 5V to 5. 5V • DC-40 MHz operation • 128 bytes of on-chip scratchpad RAM • 4K bytes of on-chip mask ROM • 64K bytes program memory address space • 64K bytes data memory address space • Four 8-bit bidirectional ports • Two 16-bit timer/counters • One full duplex serial port • Seven-source, two-level interrupt capability • One extra 4-bit bit-addressable I/O port • Two additional external interrupts INT2 / INT3 • Watchdog timer • EMI reduction mode • Built-in power management • Code protection • Packages:
− DIP 40: W78C51D-24/40 − PLCC 44: W78C51DP-24/40 − QFP 44: W78C51DF-24/40
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Publication Release Date: January 1999 Revision A1
Preliminary W78C51D
PIN CONFIGURATIONS
40-Pin DIP (W78C51D)
P1. 0 P1. 1 P1. 2 P1. 3 P1. 4 P1. 5 P1. 6 P1. 7 RST RXD, P3. 0 TXD, P3. 1 INT0, P3. 2 INT1, P3. 3 T0, P3. 4 T1, P3. 5 WR, P3. 6 RD, P3. 7 XTAL2 XTAL1 VSS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 40 ...
W78C51D PDF File
