W78C31B Datasheet | Winbond

DESCRIPTION The W78C31B microcontroller supplies a wider frequency range than most 8-bit microcontrollers on the market. It is patible with the industry standard 80C31 microcontroller series. The W78C31B contains four 8-bit bidirectional parallel ports, two 16-bit timer/counters, and a serial port. These peripherals are supported by a five-source, two-level interrupt capability. There are 128 bytes of RAM, and the device supports ROMless operation for application programs. The W78C31B 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 - 8-bit CMOS microcontroller - Fully static design - Low standby current at full supply voltage - DC-40 MHz operation - 128 bytes of on-chip scratchpad RAM - ROMless operation - 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 - Boolean processor - Five-source, two-level interrupt capability - Built-in power management - Packages: - DIP 40: W78C31B-16/24/40 - PLCC 44: W78C31BP-16/24/40 - QFP 44: W78C31BF-16/24/40 - TQFP 44: W78C31BM-16/24/40 -1- Publication Release Date: October 1997 Revision A3 .. PIN CONFIGURATIONS 40-Pin DIP (W78C31B) 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 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 VCC P0.0, AD0 P0.1, AD1 P0.2, AD2 P0.3, AD3 P0.4, AD4 P0.5, AD5 P0.6, AD6 P0.7, AD7 EA ALE PSEN P2.7, A15 P2.6, A14 P2.5, A13 P2.4, A12 P2.3, A11 P2.2, A10 P2.1, A9 P2.0, A8 44-Pin PLCC...