This file describes information needed for controlling the VT100 terminal from a remote computer. All of the information was derived from the VT100 user's manual, Programmer's Information section. Full documentation can be obtain >from DIGITAL'S Accessory and Supplies Group. ANSI mode w/cursor ANSI mode w/cursor Cursor Key VT52 mode key mode reset key mode set -------------------------------------------------------------------------- UP A [A OA DOWN B [B OB RIGHT C [C OC LEFT D [D OD ******************************* * Special Graphics Characters * ******************************* If the Special Graphics set is selected, the graphics for ASCII codes 0137 through 0176 will be replaced according to the following table (see the SCS control sequence). Octal ASCII Special Octal ASCII Special Code graphic graphic code graphic graphic ------------------------------------------------------------------------------- 0137 _ Blank 0157 o Horiz Line - scan 1 0140 \ Diamond 0160 p Horiz Line - scan 3 0141 a Checkerboard 0161 q Horiz Line - scan 5 0142 b Digraph: HT 0162 r Horiz Line - scan 7 0143 c Digraph: FF 0163 s Horiz Line - scan 9 0144 d Digraph: CR 0164 t Left "T" (|-) 0145 e Digraph: LF 0165 u Right "T" (-|) 0146 f Degree Symbol 0166 v Bottom "T" (|0147 g +/- Symbol 0167 w Top "T" (T) 0150 h Digraph: NL 0170 x Vertical Bar (|) 0151 i Digraph: VT 0171 y Less/Equal (<0152 j Lower-right corner 0172 z Grtr/Egual (>0153 k Upper-right corner 0173 { Pi symbol 0154 l Upper-left corner 0174 | Not equal (=0155 m Lower-left corner 0175 } UK pound symbol 0156 n Crossing lines (+) 0176 ~ Centered dot NOTE 1: Codes 0152-0156 and 0164-0170 are used to draw rectangular grids" each piece of this set is contiguous with other so the lines formed will be unbroken. NOTE 2: Codes 0157-0163 give better vertical resolution than dashes and underlines when drawing graphs; using these segments, 120 x 132 resolution may be obtained in 132 column mode with the Advanced Video Option installed. ***************************** * Terminal Control Commands * ***************************** Control Characters ------------------ The control characters recognized by the VT100 are listed below. All other control characters cause no action to be taken. Control characters (codes 00 - 037 inclusive) are specifically excluded >from the control sequence syntax, but may be embedded within a controlsequence. Embedded control characters are executed as soon as they are encountered by the VT100. The processing of the control sequence then continues with the next character recieved. The exceptions are: if the character occurs, the current control sequence is aborted, and a new one commences beginning with the just recieved. If the character (030) or the character (032) occurs, the current control sequence is aborted. The ability to embed control characters allows the synchronization characters XON and XOFF to be interpreted properly without affecting the control sequence. Control Octal Character Code Action Taken ------------------------------------------------------------------------------ 0000 Ignored on input; not stored in buffer 0005 Transmit ANSWERBACK message 0007 Sound bell 0010 Move cursor to the left one position, unless it is at the left margin, in which case no action is taken. 0011 Move cursor to the next tab stop, or to the right margin if no further tabs are set. 0012 Causes either a line feed or new line operation (See new line mode.) 0013 Same as . 0014 Same as . 0015 Move the cursor to the left margin of the current line. 0016 Invoke the G1 character set, as designated by the SCS control sequence. 0017 Invoke the G0 character set, as selected by the ( sequence. 0021 Causes terminal to resume transmission (XON). 0023 Causes terminal to stop transmitting all codes except XOFF and XON (XOFF). 0030 If sent during a control sequence, the sequence id immediately terminated and not executed. It also causes the error character (checkerboard) to be displayed. 0032 Same as . 0033 Introduces a control sequence. 0177 Ignored on input; not stored in buffer. The VT100 is an upward and downward software compatible terminal; that is, previous DIGITAL video terminals have DIGITAL's private standards for control sequences. The American National Standards Institute has since standardized escape and control sequences in terminals in documents X3.41-1974 and X3.64-1977. The VT100 is compatible with both the previous DIGITAL standard and ANSI standards. Customers may use existing DIGITAL software designed around the VT52 or new VT100 software. The VT100 has a "VT52 compatible" mode in which the VT100 responds to control sequences like a VT52. In this mode, most of the new VT100 features cannot be used. Throughout this document references will be made to "VT52 mode" or "ANSI mode". These two terms are used to indicate the VT100's software compatibility. NOTE: The ANSI standards allow the manufacturer flexibility in implementing each function. This document describes how the VT100 will respond to the implemented ANSI central function. NOTE: ANSI standards may be obtained by writing: American National Standards Institute Sales Department 1430 Broadway New York, NY, 10018 Definitions ----------- Control Sequence Introducer (CSI) - An escape sequence that provides supplementary controls and is itself a prefix affecting the interpretation of a limited number of contiguous characters. In the VT100, the CSI is: [ Parameter: (1) A string of zero or more decimal characters which represent a single value. Leading zeros are ignored. The decimal characters have a range of 0 (060) to 9 (071). (2) The value so represented. Numeric Parameter: A parameter that represents a number, designated by Pn. Selective Parameter: A parameter that selects a subfunction from a specified set of subfunctions, designated by Ps. In general, a control sequence with more than one selective parameter causes the same effect as several control sequences, each with one selective parameter, e.g., CSI Psa; Psb; Psc F is identical to CSI Psa F CSI Psb F CSI Psc F. Parameter String: A string of parameters separated by a semicolon. Default: A function-dependent value that is assumed when no explicit value, or a value of 0, is specified. Final character: A character whose bit combination terminates an escape or control sequence. EXAMPLE: Control sequence to turn off all character attributes, then turn on underscore and blink attributes (SGR). [0;4;5m Sequence: Delimiters / \ / \ | | \ / \ / [ 0 ; 4 ; 5 m ^^^^^^ ^ ^ ^ ^ |||||| | | | | \||||/ \ | / +------Final character \||/ \ | / CSI Selective Parameters The octal representation of this string is: 033 0133 060 073 064 073 065 0155 [ 0 ; 4 ; 5 m Alternate sequences which will accomplish the same thing: 1) [;4;m 2) [m [4m [5m 3) [0;04;005m Control Sequences ----------------- All of the following control sequences are transmitted from the Host to VT100 unless otherwise noted. All of the control sequences are a subset of those defined in ANSI X 3.64 1977 and ANSI X 3.41 1974. The following text conforms to these formatting conventions: 1) Control characters are designated by angle brackets (e.g. the Escape character is ). 2) Parameters are indicated by curly braces. 3) Parameter types usually are indicated as one of: {Pn} A string of digits representing a numerical value. {Ps} A character that selects an item from a list. {a-z} Any lowercase sequence of one44 or more characters in braces represent a value to be entered (as in {Pn}), and the name in the braces will be referred to in explanatory text. 4) Spaces in the control sequence are present for clarity and may be omitted. Spaces which are required will be surrounded by single quotes: ' '. 5) All other characters are literals. CPR Cursor Position Report VT100 to Host [ {Pn} ; {Pn} R Default Value: 1 The CPR sequence reports the active position by means of the parameters. This sequence has two parameter values, the first specifying the line and the second specifying the column. The default condition with no parameters present, or parameters of 0, is equivelent to a cursor at home position. The numbering of the lines depends upon the state of the Origin Mode (DECOM). This control sequence is sent in reply to a device status report (DSR) command sent from the host. CUB Cursor Backward Host to VT100 & VT100 to Host [ {Pn} D Default Value: 1 The CUB sequence move the cursor to the left. The distance moved is determined by the parameter. If the parameter missing, zero, or one, the cursor is moved one position. The cursor cannot be moved past the left margin. Editor Function. CUD Cursor Down Host to VT100 & VT100 to Host [ {Pn} B Default value: 1 Moves the cursor down a number of lines as specified in the parameter without changing columns. The cursor cannot be moved past the bottom margin. Editor Function. CUF Cursor Foreward Host to VT100 & VT100 to Host [ {Pn} C Default Value: 1 The CUF sequence moves the cursor to the right a number of positions specified in the parameter. The cursor cannot be moved past the right margin. Editor Function. CUP Cursor Position [ {Pn} ; {Pn} H Default Value: 1 The CUP sequence moves the curor to the position specified by the parameters. The first parameter specifies the line, and the second specifies the column. A value of zero for either line or column moves the cursor to the first line or column in the display. The default string (H) homes the cursor. In the VT100, this command behaves identically to it's format effector counterpart, HVP. The numbering of the lines depends upon the state of the Origin Mode (DECOM). Editor Function. CUU Cursor Up Host to VT100 & VT100 to Host [ {Pn} A Default Value: 1 Moves the cursor up without changing columns. The cursor is moved up a number of lines as indicated by the parameter. The cursor cannot be moved beyond the top margin. Editor Function. DA Device Attributes Host to VT100 & VT100 to Host [ {Pn} c Default Value: 0 1) The host requests the VT100 to send a DA sequence to indentify itself. This is done by sending the DA sequence with no parameters, or with a parameter of zero. 2) Response to the request described above (VT100 to host) is generated by the VT100 as a DA control sequencewith the numeric parameters as follows: Option Present Sequence Sent --------------------------------------------- No options [?1;0c Processor Option (STP) [?1;1c Advanced Video Option (AVO) [?1;2c AVO and STP [?1;3c Graphics Option (GPO) [?1;4c GPO and STP [?1;5c GPO and AVO [?1;6c GPO, ACO, and STP [?1;7c <<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>, <<> <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> DECALN Screen Alignment Display (DEC private) # 8 This command causes the VT100 to fill it's screen with uppercase Es for screen focus and alignment. DECANM ANSI/VT52 Mode (DEC Private) This is a private parameter to the SM and RM control sequences. The reset state causes only VT52 compatible escape sequences to be recognized. The set state causes only ANSI compatible escape sequences to be recognized. See the entries for MODES, SM, and RM. DECARM Auto Repeat Mode (DEC Private) This is a private parameter to the SM and RM control sequences. The reset state causes no keyboard keys to auto-repeat, the set state causes most of them to. See MODES, SM, and RM. DECAWM Autowrap Mode (DEC Private) This is a private parameter to the SM and RM control sequences. The reset state prevents the cursor from moving when characters are recieved while at the right margin. The set state causes these characters to advance to the next line, causing a scroll up if required and permitted. See MODES, SM, and RM. DECCKM Cursor Keys Mode (DEC Private) This is a private parameter to the SM and RM control requences. This mode is only effective when the terminal is in keypad application mode (DECPAM) and the ANSI/VT52 mode (DECANM) is set. Under these conditions, if this mode is reset, the cursor keys will send ANSI cursor control commands. If setm the cursor keys will send application function commands (See MODES, RM, and SM). DECCOLM Column Mode (DEC Private) This is a private parameter to the SM and RM control sequences. The reset state causes an 80 column screen to be used. The set state causes a 132 column screen to be used. See MODES, RM, and SM. DECDHL Double Height Line (DEC Private) Top Half: #3 Bottom Half: #4 These sequences cause the line containing the cursor to become the top or bottom half of a double-height, double width line. The sequences should be used in pairs on adjacent lines with each line containing the same character string. If the line was single width single height, all characters to the right of the center of the screen will be lost. The cursor remains over the same character position, unless it would be to the right of the right margin, in which case it is moved to the right margin. DECDWL Double Width Line (DEC Private) #6 This causes the line that contains the cursor to become double-width single height. If the line was single width, all characters ro the right of the center of the screen will be lost. The cursor remains over the same character position, unless it would be to the right of the right margin, in which case it is moved to the right margin. DECID Identify Terminal (DEC Private) Z This sequence causes the same response as the DA sequence. This sequence will not be supported in future models. DECINLM Interlace Mode (DEC Private) This is a private parameter to the RM and SM control sequences. The reset state (non-interlace) causes the video processor to display 240 scan lines per frame. The set state causes the video processor to display 480 scan lines per screen. See MODES, RM, and SM. DECKPAM Keypad Application Mode (DEC Private) = The auxiliary keypad keys will transmit control sequences. DECKPNM Keypad Numeric Mode (DEC Private) > The auxiliary keypad keys will send ASCII codes corresponding to the characters engraved on their keys. DECLL Load LEDs (DEC Private) [ {Ps} q Default Value: 0 Load the four programmable LEDs on the keyboard according to the prameter(s). Parameter Meaning ----------------------- 0 Clear All LEDs 1 Light L1 2 Light L2 3 Light L3 4 Light L4 DECOM Origin Mode (DEC Private) This is a private parameter to SM and RM control sequences. The reset state causes the origin (or home position) to be the upper left character position of the screen. Line and column numbers are, therefore, independent of current margin settings. The cursor may be positioned outside the margins with a cursor position (CUP) or horizontal and vertical position (HVP) control. The set state causes the origin to be at the upper left character position within the current margins. Line and column numbers are, therefore, relative to the current margin settings. The cursor cannot be positioned outside of the margins. The cursor is moved to the new home position when this mode is set or reset. Lines and columns are numbered consecutively, with the origin being line 1, column 1. DECRC Restore Cursor (DEC Private) 8 This sequence causes the previously saved cursor position, graphic rendition, and character set to be restored. DECREPTPARM Report Terminal Parameters VT100 to Host [ {sol} ; {par} ; {nbits} ; {xspd} ; {rspd} ; {cmul} ; {flags} x This sequence is generated by the VT100 to notify the host of the status of selected terminal parameters. The status sequence may be sent when requested by the host (via DECREQTPARM) or at the terminal's discretion. On power up or reset, the VT100 is inhibited from sending unsolicited reports. The meanings of the sequence paramters are: Parameter Value Meaning ------------------------------------------------------------------ {sol} 1 This message is a report. 2 This message is a report, and the terminal is only reporting on request. {par} 1 No parity set 4 Parity set and odd 5 Parity set and even {nbits} 1 8 bits per character 2 7 bits per character {xspd} 0 Speed set to 50 bps -and- 8 Speed set to 75 bps {rspd} 16 Speed set to 110 bps 24 Speed set to 134.5 bps {xspd}= 32 Speed set to 150 bps Transmit 40 Speed set to 200 bps Speed 48 Speed set to 300 bps 56 Speed set to 600 bps {rspd}= 64 Speed set to 1200 bps Recieve 72 Speed set to 1800 bps Speed 80 Speed set to 2000 bps 88 Speed set to 2400 bps 96 Speed set to 3600 bps 104 Speed set to 4800 bps 112 Speed set to 9600 bps 120 Speed set tp 19200 bps {cmul} 1 The bit rate multiplier is 16 {flags} 0-15 This value communicates the four switch values in block 5 of SET-UP B, which are only visible to the user when an STP option is installed. DECREQTPARM Request Terminal Parameters [ {Ps} x The host sends this sequence to request the VT100 to send a DECREPTPARM sequence back. {Ps} can be either 0 or 1. If 0, the terminal will be allowed to send unsolicited DECREPTPARMs. These reports will be generated each time the terminal exits the SET-UP mode. If {Ps} is 1, then the terminal will only generate DECREPTPARMs in response to a request. DECSC Save Cursor (DEC Private) 7 Causes the cursor position, graphic rendition, and character set to be saved. (See DECRC) DECSCLM Scrolling Mode (DEC Private) This is a private parameter to RM and SM control sequences. The reset state causes scrolls to "jump" instantaneuously one line at a time. The set state causes the scrolls to be "smooth", and scrolls at a maximum rate of siz lines/sec. See MODES, RM, and SM. DECSCNM Screen Mode (DEC Private) This is a private parameter to RM and SM control sequences. The reset state causes the screen to be black with white characters; the set state causes the screen to be white with black characters. See MODES, RM, and SM. <<<>>> DECSTBM Set Top and Bottom Margins (DEC Private) [ {Pn} ; {Pn} r Default Values: See Below This sequence sets the top and bottom margins to define the scrolling region. The first parameter is the line number of the first line in the scrolling region; the second parameter is the line number of the bottom line of the scrolling region. Default is the entire screen (no margins). The minimum region allowed is two lines, i.e., the top line must be less than the bottom. The cursor is placed in the home position (See DECOM). DECSWL Single-width Line (DEC Private) #5 This causes the line which contains the cursor to become single-width, single-height. The cursor remains on the same character position. This is the default condition for all new lines on the screen. DECTST Invoke Confidence Test [ 2 ; {Ps} y Ps is the parameter indicating the test to be done. It is computed by taking the weight indicated for each desired test and adding them together. If Ps is 0, no test is performed but the VT100 is reset. Test Weight -------------------------------------------------------------- POST (ROM checksum, RAM NVR, keyboardm and AVO) 1 Data Loop Back (Loopback connector required) 2 EIA Modem Control Test (Loopback connector req.) 4 Repeat Testing until failure 8 DSR Device Status Report Host to VT100 & VT100 to Host [ {Ps} n Requests and reports the general status of the VT100 according to the following parameters: Parameter Meaning --------------------------------------------------------------- 0 Response from VT100 - Ready, no faults detected 3 Response from VT100 - Malfunction Detected 5 Command from host - Report Status (using a DSR control sequence) 6 Command from host - Report Active Position (using a CPR sequence) DSR with a parameter of 0 or 3 is always sent as a response to a requesting DSR with a parameter of 5. ED Erase in Display [ {Ps} J Default: 0 This sequence erases some or all of the characters in the display according to the parameter. Any complete line erased by this sequence will return that line to single width mode. Editor Function. Parameter Meaning ---------------------------------------------------------------- 0 Erase from the cursor to the end of the screen. 1 Erase from the start of the screen to the cursor. 2 Erase the entire screen. EL Erase in Line [ {Ps} K Default: 0 Erases some or all characters in the active line, according to the parameter. Editor Function. Parameter Meaning --------------------------------------------------------------- 0 Erase from cursor to the end of the line. 1 Erase from the start of the line to the cursor. 2 Erase the entire line. HTS Horizontal Tab Set H Set a tab stop at the current cursor position. Format Effector. HVP Horizontal and Vertical Position [ {Pn} ; {Pn} f Moves the cursor to the position specified by the parameters. The first parameter specifies the line, and the second specifies the column. A parameter of 0 or 1 causes the active position to move to the first line or column in the display. In the VT100, this control behaves identically with it's editor counterpart, CUP. The numbering of hte lines depends upon the state of the Origin Mode (DECOM). Format Effector. IND Index D This sequence causes the cursor to move downward one line without changing the column. If the cursor is at the bottom margin, a scroll up is performed. Format Effector. LNM Line Feed/New Line Mode This is a parameter to SM and RM control sequences. The reset state causes the interpretation of the character to imply only vertical movement of the cursor and causes the RETURN key to send the single code . The set state causes the character to imply movement to the first position of the following line, and causes the RETURN key to send the code pair . This is the New Line option. This mode does not affect the Index (IND) or the next line (NEL) format effectors. MODES The Following is a list of VT100 modes which may be changed with Set Mode (SM) and Reset Mode (RM) controls. ANSI Specified Modes Parameter Mnemonic Function ------------------------------------------------------------------ 0 Error (Ignored) 20 LNM Line Feed/New Line Mode DEC Private Modes If the first character in the parameter string is ? (077), the parameters are interpreted as DEC private parameters according to the following: Parameter Mnemonic Function ------------------------------------------------------------------- 0 Error (Ignored) 1 DECCKM Cursor Key 2 DECANM ANSI/VT52 3 DECCOLM Column 4 DECSCLM Scrolling 5 DECSCNM Screen 6 DECOM Origin 7 DECAWM Auto Wrap 8 DECARM Auto Repeat 9 DECINLM Interlace Any other parameter values are ignored. The following modes, which are specified in the ANSI standard, may be considered to be permanently set, permanently reset, or not applicable, as noted. Mnemonic Function State ------------------------------------------------------ CRM Control Representation Reset EBM Editing Boundary Reset ERM Erasure Set FEAM Format Effector Action Reset FETM Format Effector Transfer Reset GATM Guarded Area Transfer NA HEM Horizontal Editing NA IRM Insertion-replacement Reset KAM Keyboard Action Reset MATM Multiple area transfer NA PUM Positioning Unit Reset SATM Selected Area Transfer NA SRTM Status Reporting Transfer Reset TSM Tabulation Stop Reset TTM Transfer Termination NA VEM Vertical Editing NA NEL Next Line E This cuases the cursor to move to the first position of the next line down. If the cursor is on the bottom line, a scroll is performed. Format Effector. RI Reverse Index M Move the cursor up one line without changing columns. If the cursor is on the top line, a scroll down is performed. RIS Reset to Initial State c Resets the VT100 to the state is has upon power up. This also causes the execution of the POST and signal INT H to be asserted briefly. RM Reset Mode [ {Ps} ; {Ps} l Resets one or more VT100 modes as specified by each selective parameter in the parameter string. Each mode to be reset is specified by a separate parameter. See MODES and SM. SCS Select Character Set The appropriate D0 and G1 character sets are designated from one of the five possible sets. The G0 and G1 sets are invokedd by the characters and , respectively. G0 Sets G1 Sets Sequence Sequence Meaning ------------------------------------------------------------------ (A )A United Kingdom Set (B )B ASCII Set (0 )0 Special Graphics (1 )1 Alternate Character ROM Standard Character Set (2 )2 Alternate Character ROM Special Graphics The United Kingdom and ASCII sets conform to the "ISO international register of character sets to be used with escape sequences". The other sets are private character sets. Special graphics means that the graphic characters fpr the codes 0137 to 0176 are replaced with other characters. The specified character set will be used until another SCS is recieved. SGR Select Graphic Rendition [ {Ps} ; {Ps} m Invoke the graphic rendition specified by the parameter(s). All following characters transmitted to the VT100 are rendered according to the parameter(s) until the next aoccurrence of an SGR. Format Effector. Parameter Meaning --------------------------------------------------------------- 0 Attributes Off 1 Bold or increased intensity 4 Underscore 5 Blink 7 Negative (reverse) image All other parameter values are ignored. Without the Advanced Video Option, only one type of character attribute is possible, as determined by the cursor selection; in that case specifying either underscore or reverse will activate the currently selected attribute. SM Set Mode {Ps} ; {Ps} h Causes one or more modes to be set within the VT100 as specified by each selective parameter string. Each mode to be set is specified by a seperate parameter. A mode is considered set until it is reset by a Reset Mode (RM) control sequence. See RM and MODES. TBC Tabulation Clear [ {Ps} g If the parameter is missing or 0, this will clear the tab stop at the cursor's position. If it is 3, this will clear all of the tab stops. Any other parameter is ignored. Format Effector. ___ ( /_)_---_------------------------------------------------- (_/ ( ! / ) Petri Virekoski ------ pev@vipu.hut.fi ------ -------!/---------------------------------------------------