CONOUT Escape Sequences These are the escape functions interpreted by the BIOS' conout() function. For the most part they emulate a VT-52 terminal. There are extensions to hack screen colors, con- trol screen wrap, and a few other simple functions. ESC A Cursor Up This sequence moves the cursor up one line. If the cursor is already on the top line of the screen, this sequence has no effect. ESC B Cursor Down This moves the cursor down one line. If the cursor is already on the last line of the screen, this escape sequence has no effect. ESC C Cursor Forward This moves the cursor one position to the right. If this function would move the cursor off the screen, this sequence has no effect. ESC D Cursor Backward This move the cursor one position to the left. This is a non- destructive move because the character over which the cursor now rests is not replaced by a blank. If the cursor is already in column O, this escape sequence has no effect. ESC E Clear Screen (and Home Cursor) This moves the cursor to column O, row I (the top left-hand corner of the screen), and clears all charac- ters from the screen. ESC H Home Cursor This move the cursor to column O, row O. The screen is NOT cleared. ESC I Reverse Index Moves the cursor to the same horizontal position on the preceding lines. If the cursor is on the top line, a scroll down is performed. ESC J Erase to End of Page Erases all the information from cursor (including cur- sor position) to the end of the page. ESC K Clear to End of Line This sequence clears the line from the current cursor position to the end of the line. ESC L Insert Line Inserts a new blank line by moving the line that cursor is on, end all following lines, down one line. Then, the cursor is moved to the beginning of the new blank line. ESC M Delete Line Deletes the contents of the line that the cursor is on, places the cursor at the beginning of the line, moves all the following lines up one line, and adds a blank line at the bottom. ESC Y Position Cursor The two characters that follow the "Y" specify the row and column to which the cursor is to be moved. The first character specifies the row, the second specifies the colum. Rows and columns number from 1 up. ESC b Set Foreground Color The Foreground Color is the color in which the charac- ter is displayed. Escape-b must be followed by a color selection charac- ter. Only the four least significant bits of the color character are used: Bit Pattern of Control Byte: 7 6 5 4 3 2 1 0 +-----+-----+-----+-----+-----+-----+-----+-----+ | | | | | | | X | X | X | X | color index | | | | | | | +-----+-----+-----+-----+-----+-----+-----+-----+ (X = "don't care") ESC c Set Background Color This function selects Background Color, the color of the cell that contains the characters. Escape-c must be followed by a color selection charac- ter. Only the four least significant bits of the color character are used. (See diagram for ESC-b function) ESC d Erase Beginning of Display This sequence erases from beginning of the display to the cursor position. The cursor position is erased also. ESC e Enable Cursor This sequence causes the cursor to be invisible. The cursor may still be moved about on the display, using escape sequence defined in this appendix. ESC f Disable Cursor This sequence causes the cursor to be invisible. The cursor may still be moved about on the display, using escape sequences defined in this appendix. ESC j Save Cursor Position This sequence preserves the current cursor position. You can restore the cursor to the previously saved position with ESC-k. ESC k Restore Cursor Position This sequence restores the cursor to a previously saved position. If you use this sequence without having pre- viously saved the cursor position, then the cursor is moved to the home position, the top left-hand corner of the screen. ESC l Erase Entire Line This sequence erases an entire line and moves the cur- sor to the leftmost column. ESC o Erase Beginning of Line Erases from the beginning of the line to the cursor and includes the cursor position. ESC p Enter Reverse Video Mode Enters the reverse video mode so that characters are displayed as background color characters on a fore- ground colored cell. ESC q Exit Reverse Video Mode Exits the reverse video mode. ESC v Wrap at End of Line This sequence causes the first character past the last displayable position on a line to be automatically placed in the first character position on the next line. The page scrolls up if necessary. ESC w Discard at End of Line Following invocation of this sequence, after the last displayable character on a line has been reached, the characters overprint. Therefore, only the last charac- ter received is displayed in the last column position.