Question

You are entering a letter ‘B’ from an input device to be displayed on a monitor via an 8-bit microcontroller. Describe the steps/processes of the 8-bit microcontroller needs to perform to display the output on the monitor.

Answer 1

Before performing this,we have to check the compactability of the monitor and microcontroller.

**The letter B comes as a special code, and moved into the keyboard interrupt... Which stores that within a queue.

**Respective operating system checks the queue and when it is found free.."ready" for the execution of a key, we can say that it is on prompt.

**Before displaying a letter, ki tried to put it on the screen,and thereby location matters.. that is where the cursor is..

**Respective operating system will be well known about the location of the cursor, and represent a location in the video card memory.

**Operating system on ready knows that, it's in TEXT mode, and knows about the code 66, when we press 'A', and hold that assigned to to a will go to the table in the memory..,on which pixel to print at the same location as cursor belongs to.

**ROM bitmap table check the letter B, which is represented as an ASCII code, including a bitmap from a particular "font" according to the the choosing.

**Available standard sizes are, 5*7, 8*8.. pixel size etc. According to these sizes, they are located in a video graphics memory, which represents the specific layout of the character B allocated in the memory, as a bitmap character string.. this datas are read-out, with the help of a bitmap string character from left to right, containing other spaces and characters, as a serial data, which is recorded in the monitor, in order to display.

THANKYOU SIR/MADAM..Hope this helped you..