CDP1855E

Specialty Logic Overview

The CDP1855E is a CMOS serial I/O controller manufactured by Harris Corporation. It features a single channel for asynchronous communication and supports bit-oriented protocols. The device utilizes NRZ data encoding and decoding methods. It operates with an external 8-bit data bus width and a 2-bit address bus width. The component is housed in a PDIP-28 package. It functions within a temperature range of -40°C to +85°C and has a maximum clock frequency of 2 MHz.

Specialty Logic Feature Summary

• Provides serial input/output control capabilities for microprocessor systems
• Supports asynchronous and bit-oriented communication protocols
• Integrates on-chip data RAM for buffer management

Specialty Logic Applications

• Microprocessor-based serial communication interfaces
• Asynchronous data transmission systems
• Bit-oriented protocol handling units

Specialty Logic Procurement Notes

Verify the manufacturer designation, as Harris Corporation assets were acquired by Renesas Electronics. Confirm the specific suffix indicates the correct operating temperature range and package variant. Ensure compatibility with legacy system requirements given the component's age and discontinuation status.

Specialty Logic Selection Notes

Select this component when a dedicated serial I/O controller is required for asynchronous or bit-oriented tasks. Consider the 2 MHz maximum clock speed and PDIP-28 package constraints. Evaluate if the integrated RAM suffices for buffering needs compared to modern UART alternatives.

Specialty Logic Part Context

This part belongs to the Harris CDP18xx series of microcontrollers and peripherals. These components were designed for embedded applications requiring efficient serial data handling. The CDP1855E specifically addresses the need for standalone serial interface control without heavy CPU overhead.

Specialty Logic FAQ

What communication protocols does the CDP1855E support?

The CDP1855E supports both asynchronous (ASYNC) and bit-oriented (BIT) communication protocols.

What is the data encoding method used by this controller?

The device uses Non-Return-to-Zero (NRZ) data encoding and decoding methods.