Introduction - If you have any usage issues, please Google them yourself
Used in hardware devices: LCD liquid crystal display, keyboard, toggle switch. Operating system, the top of the LCD display the original text, the bottom of the screen shows " R: W:" - enter the characters in the original text characters compared, if the input is correct, then the R++, if the input error, then W++ . Enter the characters displayed in the third line, the second line is blank line. When the line is entered, when finished, the system stays in the current page, if there are fluctuations in switching movements, then switch to the next page, displays the next group to display the original text (10 characters). Systems of such a cycle continues.