Experimental input mapping between NVT ASCII and UCSB On Line System
Mapping network terminal keys to a specialized online system
Pickens, J.R., "Experimental input mapping between NVT ASCII and UCSB On Line System", RFC 570, DOI 10.17487/RFC0570, October 1973, <https://www.rfc-editor.org/info/rfc570>.
@misc{rfc570,
series = {Request for Comments},
number = 570,
howpublished = {RFC 570},
publisher = {RFC Editor},
doi = {10.17487/RFC0570},
url = {https://www.rfc-editor.org/info/rfc570},
author = {J.R. Pickens},
title = {{Experimental input mapping between NVT ASCII and UCSB On Line System}},
pagetotal = 1,
year = 1973,
month = oct,
} RFC text
Contents
This text was converted from the RFC Editor's PDF edition and may contain conversion errors; the layout is approximate. The PDF is the reference copy.
RFC #570Q NIC 18973 UPDATES: OBSOLETES: REFERENCES : RECEIVED AT NIC NOVEMBER 28, 1973. RFC 216 None RFC 216, RFC 398 EXPERIMENTAL INPUT MAPPING BETWEEN NVT ASCII AND UCSB ONLINE SYSTEM 30 October 1973 John R. Pickens Computer Systems Lab University of California Santa Barbara II. III. Iv. vI. Contents Motivation . . . . . . . ¢ 4 . . . . Overview . . ¢ o ¢ ¢ o 4 o o o o o o Effects on Previous Specification . Details .+ v ¢ ¢« v ¢ ¢ ¢ & o o o o A. Details of One-to-One Mapping B. Details of Two-to~-One Mapping . New or Revised SERVER TELNET Options A. OPERATOR/ALPHABET Option . . . . B. SHIFT/UNSHIFT Option . . . . . . C. INTERPRETLF/IGNORELF Option . . Conclusions and Suggestions for Easy Figures Figure 1. OLS Keyboard . . . . « ¢« « o« & Figure 2. One-to-One Mappings . . . . . . Figure 3. One-to-One Operator Mode Mappings, Expanded Figure 4. Operator Mode Mappings. . . . . Figure 5. Two-to-One Mappings . . . . . . Visual Representation of One-to-One Figfire 6. Summary of SERVER TELNET commands . . . . . s e e E W W oo 0 O W W W 10 II. MOTIVATICN Numerous requests have been received in the last six months to improve the human interface to the UCSB On-Line System (OLS) for network users. The problem stems from having to enter as many as six keys to describe a single.OLS key. For example, ;PRED[SP] must be entered to specify the key (See RFC 216, Telnet Access to UCSB's On-Line System). One solution to the problem has been to obtain and to use the custom OLS keyboard.. However, this implies a capital outlay which is not always justifiable for users with tight budgets. Thus the following solution is offered as a compromise between the ex- penée of a hardware keyboard and the awkwardness of spelled out key mappings. OVERVIEW . The OLS keyboard, pictured_in Figure 1, contains 168 meaningful keys. ASCII, the network standard for keyboards; allows only 128. Thus the mapp%ng described in this report relies on one- to-one mappings for the most common keys and two-to-one mappings using for less commonly used keys. Key assignments in ‘ the former case are picked so that location is approximately the same as pictured in Figure 1. Key aSsignments in the latter casé are picked, whgrever possible, to be suggestive of function. In addition, options exist to reenable upper and lower case alphabetics and to ignore line feeds after carriage returns. pitoqiey $10 °T eandtg : . . s3drxosxadng NYALIY | 3SVD govds . | : ’ ! W N g A ol X z asveg o oove " < > nN | ovid |vias aN | o | oIx |viaz w10 | 1as| ¢ ) ¢ 1 X r H o d a s | v 1+ J [ ] ¢ [TORYT|vadyd | VWOIS |VIIHL| VNNVO| Id | VL13a|VWOIS|VHdTY vl = M R d 0 1 n A 1 b 1 M [0 1d % $ b Id |'DIWO| VIOI|'ISdn| Isd | nvl | OHY¥ |-1Sda3|voawo| IHd ' / - * 0 6 8 L 9 S ¥ g z 1 # ? - i 0 6 | 8 | ¢ 9 s | v g z R LISTL | g : AVIdSIO . 3dvos3 _ : 43LNT 3Y0LS | AV01 ar ANOD | 13Q oYY | NVLV UMd | dX3 901 S02 NIS ld3¥ | NOD N3 XL REQ aonW XVW gns TVAZ | NMOQ dan 143y Sy S1 -1S3L| @3ud| 1u0S| Qoud| WNS | 4410 ANI | £NOD | Luds | Ds @ ORN=] %:) 1SI7 | 2dAl | ¥asn LSAS{X1dWd| 1vayu| 114 IA A Al III II I 3 \ { QivogAgEY $.0 LNIWAND III. Iv. These options (seeFigure 6) are selectable via SERVER TELNET commands following the conventions of RFC 216. EFFECTS ON THE PREVIOUS SPECIFICATION The one-to-one and two-to-one mappings described herein fall completely within the previous specification of UCSB's teletype- compatible interface. At any time the user may specify an operator using the old style prefix and spelling. The old SERVER TELNET commands still apply. It is suggested, however, that the user change his prefix to be other than ;Aso that ; may be sent as a single key. All UCSB sockets which allow TELNET input may uée this new mapping. The socket which supports graphics display on TEKTRONIX series 4000 terminals and one socket which issues NGP0 output are two such cases. (See RFC 398 fior a listing of UCSB's graphic sockets.) Control characters, which were ignored in the previous specifi- cation, now map always into operators. Figures 3 and 4 show this mapping. DETAILS A. Details of One-to-One Mapping One-to-one mappings exist for A-2Z, 0-9, most punctuation, ERASE, and most upper keyboard operators. The mapping for operators is accomplished with upper case alphabetics and control characters . MODE TO PUSH OLS OLS EXPLANATION SEND ASCII BOTH MODES| 0-9 Numerics 0-9 [SPACE] [RETURN] Punctuation BACK BACK] [TAB] s<.>25 <225 (01&*s (la*s =5+1- s%+l- I:_':_ Ia'\”(_ LINEFEED DOWN (¥) ERASE Erase Screen DEL USER] - * Operators ta-tz OPERATOR A-Z UC Alphabetics a-z [LS]- [SIN]* Operators CA-Z ALPHABET A-Z UC Alphabetics A-Z a-z*% LC Alphabetics a-z Figure 2. One-to-One Mappings * See Figures 3 and 4. **3-2z is actually Alpha-Zeta for local users. users will see and use these keys as a-z. However, network ' ~ LOWER UPPER ASCII SHIFT SHIFT - CONTROL - a A LS USER b B ATAN DISPLAY c c LOG RESET d D REFL LIST e E . II £ F uP ENTER g G DOWN REPT h H EVAL BACK i 1 INV (TAB)* 3 J SUB (¥) * k K MAX LOAD 1 L MOD STORE n M DEL (CR) * ° n N ARG ip o 0 DIFF CMPLX p p SUM SYST q Q % g T R 111 s s RS TYPE t T sQ v u u CONJ REAL ~ v v _ EXP CTX ‘w W I - x X cos . PHR y Y SQRT v z z SIN . NEG Figure 3. One-to-One Operator Mode Mappings, Expanded * [TAB] ,, and ICR! are not really operator keys, but are included to be compatible with ASCII. JNTROL — 3 T 1T TIT IV v REAL [ TAE | CMPLX | SYST “PER — | @ ® ® ) - SQ | SQRT CONJ | INV | DIFF SUM WER — Q W E R T Y U I ) P CONTROL —> T "USER T TYPE | LIST |ENTER | REPT [(BACK) | (%) LOAD |STORE UPPER — LS RS REFL | uP DOWN | EVAL | SUB MAX MOD LOWER —— A S D E G H J K L CONTROL — | NEG PWR |RESET CTX |DISPL | 1ID (CR) UPPER — | SIN cos | Loc EXP |[ATAN | ARG DEL LOWER —— Z X C v B N M ~ “Figure 4. Visual Representation of One-to-One Operator Mappings in the OPERATOR mode. ALPHABET mode sacrifices the upper case portion of this mapping, but don't panic. may be used to return to OPERATOR mode for a single key (see details of Two-to- One Mapping). FPFigures 2, 3, and 4 contain the details of the one-to-one mapping. The ASCII keys FS, GS, RS, US, °, \ PR S T are currently unassigned and may be used as convenient command prefixes. B. Details of Two-to-One Mapping Two-to-one mappingé exist 'for the remainder‘of the OLS keys. 1In all cases the first key of the two key sequence is . Either of two actions may be performed by depending upon the successor key. If the successor is not an alphabetic the appropriate OLS key will be selected independent of mode, as ocutlined in Figure 5. For example, [ESC|? will always give the [TEST] key. 1If the successor is an alphabetic then it is inter- preted as though the opposite mode were in effect (i.e. GENERATOR is the opposite of ALPHABET). This may seem confusing, but some useful effects are generated and will be illustrated by the ‘ following two examples. » 1. If while in OPERATOR mode the keys [ESCla are entered the interpretation will be "a" (as in ALPHABET mode) rather than "A". Thus users may enter lower case alphabetics while in OPERATOR mode. 2. If while in ALPHABET mode the keys [ESC]A are entered, the interpretation will be (as in OPERATOR mode) rather than "A". Thus users may enter the operators [TS] - [SIN]while in ALPHABET mode. The entire mapping is outlined in Figure 5. * % \ MODE TO PUSH OLS OLS EXPLANATION SEND ASCII BOTH MODES Shift 0 Shift Numerics [Esc]o-[ESC]9 -Shift 9 ¢ Cent Sign [ESC]$ + Line Feed Up TEST Operators ? PRED # SORT % conv [(Esch CASE [ESC] ( ENL, CON . [ESC] >, [ESC]< VI,VII &, ! PT [EsC] - SET,CLR [Esc]+, [ESC] - OPERATOR A-Z* [ UC Alphabetics A- Z a-z LC Alphabetics [ESC]a-[ESC]z ALPHABET A-2* UC Alphabetics [ESC]a- z - Operators A- z Figure 5. Two-to-One Mappings *These cases are degenerate and minimally useful, but are A-Z is best sent by a-z in OPERATOR Mode and A-Z in ALPHABET Mode. included for completeness. **Note: in actual usage these keys might be best handled by spelling them out rather than looking at a chart. New or Revised SERVER TELNET Options#* A. OPERATOR/ALPHABET Option A new option set by the OPERATOR command enables the one-to-one mapping described above. The ALPHABET command restores the .interpretation of lower/upper case alphabetics to that of RFC #216. Users of the OPERATOR mode will seldom returfl to ALPHABET mode. When ALPHABET mode is invoked, however, it will probably be to use message generation on the TYPE level or upper/lower case file creation using COL. B. SHIFT/UNSHIFT Option Another option, set by the SHIFT command, reverses the interpre- tation of upper/lower case ASCII alphabetics. For example, if SHIFT is invoked while in ALPHABET mode, a lower case "a" would receive an upper case "A" ipterpretation (i.e. send an OLS "a"). Or while in OPERATOR and SHIFT modes a lower case "a" would receive the upper case "A" interpretation, LS. The SHIFT option was useful in the p{eviogs specification to gain convenient access to upper case. For this new specification, however, its usefulness is minimal, but might be used for a user who would rather map upper case ASCII to upper case OLS and lower case ASCII to operators. ~ *See Figure 6 for a summary of all available commands. VI. C. INTERPRETLF/IGNORELF Option The options INTERPRETLF/IGNORELF exist due to the desire to map directly into the OLS key [¥] (located over ). Some terminals always send following . For these ‘terminals IGNORELF ignores the trailing ]L [, thus avoiding spurious sends of to OLS. Most terminals, however, allow the separation of and . For these, INTERPRETLF can be used to cause all keys to be interpreted as. CONCLUSIONS AND SUGGESTIONS FOR EASY USAGE For these mappings to be most usef_ul, the user should have tape- on labels for the fronts of keys A-Z and tA-tZ (the same keys for most kej,'boards) . ' A reference card summarizing double keypushes and special modes completes the necessary equipment. The Computer Systems Lab will work with individuals to create customized label sets. It is hoped that the current experimental mapping will provide more convenient input to the UCSB OLS. As network graphics protocols become better defined, UCSB hopes also to enable more output features not now available to network users. Any criticisms, comments, or suggestions with this and future improvements should be sent via network mail (e.g. SNDMSG) to GRIPE at UCSB-MOD75. 10 COMMAND MEANING *HELP Lists all NETOLS commands. PREFIX (default=;) Change NETOLS command prefix. SHIFT Lower and upper case ASCII is inter- preted as upper and lower case ASCII, respectively. UNSHIFT (default) Lower and upper case ASCII is inter- preted as lower and upper case ASCII, respectively. *FULLDUPLEX _ Causes NETOLS to echo all characters. *HALF DUPLEX (default) Disables NETOLS character echoing. *STATE Displays status of all options. - LOGOUT Sign off and break connection. IGNORELF Ignore any m following n INTERPRETLF (default) Interpret E following m as in Figure 2. OPERATOR ° __ Lower case and upper case ASCII are interpreted as upper case alphabetlcs and operators respectively. ALPHABET (default) Lower case and upper case ASCII are interpreted as lower case (greek) and upper case alphabetics, respectively. Figure 6.. Summary of SgRVER TELNET commands *These commands are ignored on all sockets which output graphics.
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On this page
§1Bridging a Keyboard Gap
The UCSB On-Line System (OLS) is a specialized system with a 168-key custom keyboard containing mathematical operators, function keys, and control functions not present on standard ASCII keyboards. The network terminal standard, NVT ASCII, supports only 128 characters. Previously, network users accessing OLS had to enter escape sequences like ;PRED[SP] (six characters) to specify a single OLS key. This made remote use cumbersome and slow, and many users wanted a custom OLS keyboard for their local machine, which was expensive. RFC 570 proposes a middle ground: a practical character mapping that gives network users faster access to OLS functionality without requiring specialized hardware.
OLS has lots of special keys that network keyboards do not have. To use them over the network, you had to type six characters for one key. This mapping makes it take one or two characters instead.
§2One-to-One and Two-to-One Mappings
The mapping uses one-to-one assignment for the most common 80 or so OLS keys: alphanumerics (A-Z, 0-9), space, return, tab, punctuation, erase, and many operator keys. In USER (OPERATOR) mode, uppercase letters map to OLS operators, and lowercase ASCII triggers two-character sequences. In ALPHABET mode, lowercase and uppercase ASCII map directly to OLS alphabetics.
Two-to-one mapping uses the ESC character as a prefix: [ESC] followed by a character selects less common keys (shifted numerics, special operators like PRED, SORT, CONV, TEST). For example, [ESC]? selects the TEST key. If the character after ESC is alphabetic, it is interpreted in the opposite mode (e.g., [ESC]a in OPERATOR mode gives lowercase 'a', allowing users to type both operators and lowercase letters in OPERATOR mode).
Regular letters and numbers map directly. Special keys use ESC plus another key. Modes switch how letters are interpreted so you can type both operators and regular text without changing mode much.
§3Modes and Options
The RFC defines several options. OPERATOR/ALPHABET switches the mode for letter interpretation. SHIFT/UNSHIFT reverses uppercase and lowercase interpretation. INTERPRETLF/IGNORELF controls whether a line feed after a carriage return is treated as a separate DOWN arrow key (common with some terminals) or ignored (since regular terminals send CR-LF as a pair for carriage return). The RFC recommends using key labels on standard keyboards to help users remember the mapping and a reference card for two-key sequences. All of these options are selectable via SERVER TELNET commands, following previous UCSB telnet specifications.
You can switch between modes: OPERATOR mode for functions, ALPHABET mode for text. You can reverse uppercase and lowercase if your keyboard sends them oddly. You can ignore extra line feeds that some terminals send.