1 / 25

8255 – PROGRAMMABLE PARALLEL PORT DEVICE

8255 – PROGRAMMABLE PARALLEL PORT DEVICE. METHODS OF PARALLEL DATA TRANSFER. SIMPLE INPUT AND OUTPUT SIMPLE STROBE I/O SINGLE-HANDSHAKE I/O DOUBLE HANDSHAKE I/O. HANDSHAKE INPUT DATA TRANSFER SIGNAL DIRECTIONS. MICRO- PROCESSOR. PORT DEVICE. PERIPHERAL. PARALLEL DATA LINES.

inga-blevins
Download Presentation

8255 – PROGRAMMABLE PARALLEL PORT DEVICE

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 8255 – PROGRAMMABLE PARALLEL PORT DEVICE

  2. METHODS OF PARALLEL DATA TRANSFER • SIMPLE INPUT AND OUTPUT • SIMPLE STROBE I/O • SINGLE-HANDSHAKE I/O • DOUBLE HANDSHAKE I/O

  3. HANDSHAKE INPUT DATA TRANSFER SIGNAL DIRECTIONS MICRO- PROCESSOR PORT DEVICE PERIPHERAL PARALLEL DATA LINES STB ACK

  4. Need of 8255 • The parallel port device 8255 has been designed to automatically manage the handshake operation. • Eg, it can be programmed to automatically receive an Strobe signal from a peripheral, send an int signal to the processor and send the ACK signal back to the peripheral at proper times

  5. 8255 – Internal block diagram

  6. Note: 8255 is often used in mode 1

More Related