IC 8255 is a programmable input / output peripheral interface. This IC has three numbers of 8 bit I/O ports. By programming, each port can be configured to be an input mode or output mode. This is achieved by connecting this module to a Microprocessor unit, as an input / output. This module makes use of, 8255s used in Microprocessor trainer. This IC can be programmed

in three modes. They are: Basic Input / output (mode 0), strobed I/O (mode - 1), strobed Bi-directional Bus I/O (mode 2). To experiment an 8255 for the above, the trainer is provided with 8 bit Switches, 2 bit independent, de-bounced pulsar outputs, 8 bit tri-state buffer amplifier, 8 bit LED indicator and a built-in power supply. In addition to this, an ergonomically designed front panel with spring activated connecting terminals are provided. With these facilities, this trainer will be self-sufficient. In short using this trainer, all the above modes can be experimented.

Specifications:

• 8 bit SPDT switches and 8 bit LEDs.
  
• Independent de-bounced pulsar switches- 2 Nos.
  
• 8 bit tri-state buffer amplifiers.
  
• Spring activated connecting terminals at appropriate places.
  
• Built-in power supply.

Note: This experimental module can be interfaced to all Microprocessor trainers, Micro control trainers or IBM PC Add – on card Model: IBL-IBR-1.