Rockwell R65C21 Peripheral Interface Adapter Datasheet

About this manual

The R65C21 Peripheral Interface Adapter (PIA) is a low‑power CMOS device that provides two 8‑bit bidirectional I/O ports and four interrupt inputs for microprocessor‑based systems such as the R6500, R6500/​2 or R65C00 families. It offers flexible handshaking and can be used as a direct replacement for NMOS R6520 or MC6821 parts.

Key features include selectable operating frequencies (1 MHz to 4 MHz), multiple temperature‑range options, and a variety of package styles (40‑pin ceramic DIP, 40‑pin plastic DIP, 44‑pin PLCC). The PIA operates from a single +5 Vdc supply and provides robust I/O buffering capable of sinking up to 3.2 mA per line.

What's inside

• Description
• Features
• Ordering Information
• Interface Signals
• Control Registers
• Interrupt Request Lines
• Peripheral I/O Ports
• Data Bus Buffers

Specifications

Frequently asked questions

What power supply voltage does the R65C21 require?

The R65C21 operates from a single +5 Vdc power supply.

What package options are offered for the R65C21?

The device is available in 40‑pin ceramic DIP, 40‑pin plastic DIP, and 44‑pin PLCC packages.