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Terminal Compatibility CONSOLE TERMINAL Most operating systems, and JANOS is no exception, utilize some form of Command Line Interface. With the JNIOR, the command line can be accessed serially through the RS-232 (COM) port at 115,200 baud, 8 data bits, 1 stop bit and no parity. Typically these days this is accomplished with a USB-To-Serial adapter and a terminal program. When the JNIOR is properly configured for the network, any number of Telnet client programs can be used to access the command line. With the Series 4 JNIOR one can also open the default Dynamic Configuration Pages (WebUI) using a standard browser. In this case the command line is referred to as a Console Session and you can login via the Console tab. The command line interface uses the standard ASCII character set and is not graphical. Telnet client programs and terminal emulators communicate on a character by character basis allowing you to utilize the features of the JANOS command line. In general a program supporting the ANSI or VT-100 escape sequences is required. While you can interact successfully with only a basic terminal passing keystrokes and displaying characters, the experience is greatly improved when the correct emulation is in place. JANOS utilizes only a basic subset of the VT-100 codes. These will be outlined below. It is recommended that any custom terminal emulation program be written to support these sequences. KEYBOARD EMULATION Keystrokes are sent to the JNIOR for processing. If appropriate they are echoed for display by the JNIOR. ASCII characters fall into the range 0 to 127 which encompasses the standard character set with punctuation and a series of control characters (values less than 32). There are a number of special keys on the standard computer keyboard that do not translate into individual ASCII codes. Fortunately the JNIOR utilizes only a few special keys. With VT-100 emulation these keys are automatically translated into an escape sequence. The custom terminal emulator must enable these translations. The following are used by the command line interface: Cursor Emulation, Positioning and Editing Up Arrow ESC[A Down Arrow ESC[B Right Arrow ESC[C Left Arrow ESC[D Home Key ESC[1~ End Key ESC[4~ Page Up Key ESC[5~ Page Down Key ESC[6~ Ins Key ESC[2~ Note that the Backspace Key is assumed to translate to an ASCII 0x08. The Delete Key (Del) should translate to an ASCII 0x7F (127) code. In terminal programs (e.g. PuTTY) this behavior can be customized. CONTROL CODES Control codes are ASCII values between 0 and 0x1F (31 decimal) inclusive. They have various meanings. In particular the following are used by the JNIOR. Ctrl-A 0x01 (1 decimal) toggles anchor used in text selection [2] Ctrl-C 0x03 (3 decimal) cancels current actions, displays the banner, editor selection copy [2] Ctrl-H 0x08 (8 decimal) backspace - Backspace Key Ctrl-I 0x09 (9 decimal) tab toggles filename auto-fill [1], advances to tab stops in editing [2] - Tab Key Ctrl-M 0x0D (13 decimal) Carriage return Enter Key Ctrl-Q 0x11 (17 decimal) Exits editor [2] Ctrl-V 0x16 (22 decimal) Editor selection paste [2] Ctrl-X 0x18 (24 decimal) Editor selection cut [2] Ctrl-Y 0x19 (25 decimal) Editor Redo [2] Ctrl-Z 0x1A (26 decimal) Editor Undo [2] Ctrl-[ 0x1B (27 decimal) Editor Escape [2] - Esc Key [1] JNIOR Series 4 feature [2] JANOS v2 feature. SCREEN EDITOR The JNIOR Series 3 and Series 4 with JANOS v1 operating code do not utilize escape sequences to manipulate displayed character data. The following are required by JANOS v2 specifically to support the the screen editor EDIT . Where shown the '#' is replaced by a numeric value represented by ASCII digits. This indicates the number of times that the action is to be repeated. If the decimal value is omitted it is assumed to be one (1). Move cursor Up ESC[#A Move cursor Down ESC[#B Move cursor Right ESC[#C Move cursor Left ESC[#D Erase from cursor to end of line ESC[K Format character normal ESC[0m Format character reverse video (selected) ESC[7m Disable Line Wrap ESC[?l Note that the UP and DOWN arrow movements move to the same column in the line above or below on the display respectively. If the destination line is shorter and does not extend to the target column the cursor is moved to the after the last position on the new line. A RIGHT arrow is ignored once the cursor reaches the end of the line. A LEFT arrow is ignored if the cursor is positioned at the beginning of the line. In other words there is no wrap. The logic for this is handled by JANOS. So if your terminal emulation handles movements differently the result should still be as described here. The Disable Line Wrap escape sequence is sent when the screen editor is started. Lines that wrap would cause confusion with page oriented editing. This wrapping feature is to be disabled. The character formatting is used in highlighting characters when being selected for Copy, Cut and Paste operations. The editor cannot detect the state of the Shift key and relies on dropping the Ctrl-A anchor to start highlighting. Characters are then highlighted as the cursor is moved. Terminal emulation that does not support the formatting of individual characters (e.g. HTML textarea) can accomplish the selection highlighting by some other means. The formatting escape sequences should be ignored in that case. The cursor movement and line erasure escape sequences are critical in enabling a functional screen oriented editor. [/flash/manpages/reference.hlp:713]