The W65C22S Versatile Interface

Interface (computer science)

In the field of computer science, an interface is a tool and concept that refers to a point of interaction between components, and is applicable at the level of both hardware and software...

 Adapter (VIA) is an I/O device for use with the 65xx series

MOS Technology 65xx

MOS Technology 65xx is a family of 8-bit microprocessors from MOS Technology, based on the Motorola 6800 . The 65xx family most notably included the 6502, used in several home computers such as the Commodore PET and VIC-20, the Apple II, and the Atari 800.One popular 6502 based computer, the...

 microprocessor family. The W65C22S is compatible with the MOS Technology 6522

MOS Technology 6522

The 6522 Versatile Interface Adapter was an integrated circuit made by MOS Technology, as well as second sources including Rockwell and Synertek. It served as a I/O port controller for the 6502 family of microprocessors, providing the parallel I/O capabilities of the PIA as well as timers and a...

 and includes functions for programmed control of two peripheral ports (Ports A and B). Two program controlled 8-bit bi-directional peripheral I/O ports allow direct interfacing between the microprocessor and selected peripheral units.

Each port has input data latching capability. Two programmable Data Direction Registers (A and B) allow selection of data direction (input or output) on an individual line basis.

Also provided are two programmable 16-bit Interval Timer/Counters with latches. Timer 1 may be operated in a One-Shot Interrupt Mode with interrupts on each count-to-zero, or in a Free-Run Mode with a continuous series of evenly spaced interrupts. Timer 2 functions as both an interval and pulse counter.

Serial Data transfers are provided by a serial to parallel/parallel to serial shift register. Application versatility is further increased by various control registers, including an Interrupt Flag Register, an Interrupt Enable Register and two Function Control Registers. The IRQB output is an open drain.

Features

• Advanced CMOS process technology for low power consumption
• Compatible with NMOS 6522 devices
• Low power consumption
• Two 8-bit, bi-directional peripheral I/O Ports
• Two 16-bit programmable Interval Timer/Counters
• Serial bi-directional peripheral I/OPort
• Enhanced "handshake" feature
• Latched Input/Output Registers on both I/OPorts
• Programmable Data Direction Registers
• TTL compatible I/O peripheral lines
• Single 1.8V to 5V power supply
  Power supply
  A power supply is a device that supplies electrical energy to one or more electric loads. The term is most commonly applied to devices that convert one form of electrical energy to another, though it may also refer to devices that convert another form of energy to electrical energy...
  
  
• Bus compatible with high-speed W65C02S and W65C816S
• Register and Chip Selects specified for multiplexed operation

External links

• W65C22S Datasheet from a Western Design Center
  Western Design Center
  The Western Design Center , located in Mesa, Arizona, USA, is a company developing and manufacturing MOS 65xx-based microprocessors, microcontrollers , and related support chips...
  
  website