Question: . . Consider a computer system that contains an I/O module controlling a simple keyboard/printer Teletype. The following registers are contained in the CPU and

 . . Consider a computer system that contains an I/O module

. . Consider a computer system that contains an I/O module controlling a simple keyboard/printer Teletype. The following registers are contained in the CPU and connected directly to the system bus: INPR: Input Register, 8 bits OUTR: Output Register, 8 bits FGI: Input Flag, 1 bit FGO: Output Flag, 1 bit IEN: Interrupt Enable, 1 bit Keystroke input from the Teletype and output to the printer are controlled by the I/O module. The Teletype is able to encode an alphanumeric symbol to an 8-bit word and decode an 8-bit word into an alphanumeric symbol. The Input flag is set when an 8- bit word enters the input register from the Teletype. The Output flag is set when a word is printed. 1. Describe how the CPU, when using the first 4 registers listed above, can achieve I/O with the Teletype. Code or algorithm descriptions at the level of pseudo-code would be appropriate as part of this discussion/answer. 2. Describe how the function in (a) is inefficient, and how it can be performed more efficiently by also employing IEN

Step by Step Solution

There are 3 Steps involved in it

1 Expert Approved Answer
Step: 1 Unlock blur-text-image
Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock
Step: 3 Unlock

Students Have Also Explored These Related Databases Questions!