HP-71B BASIC Reference — Programmer's Guide & Keyword Index

Keyboard & Modes

Shifts: f (gold, above keys) · g (blue, below keys). Release the shift before or hold it while pressing the key. Letters are uppercase; g+letter gives the other case; fLC toggles lowercase mode (flag −15).

Key	Action
`END LINE`	Execute / enter the line (like RETURN)
`ATTN`	Clear display; halt a running program (SUSP). Also the ON key
`fOFF` / `ON`	Power off / on (auto-off after 10 min unless flag −3 set)
`fCALC`	Toggle CALC mode ↔ BASIC mode
`RUN`	Run current file (or resume) · in CALC: show next partial result
`fCONT`	Continue a suspended program
`fSST`	Single-step one statement (or one CALC step)
`fUSER`	Toggle User keyboard · `g1USER` = User kbd for next key only
`gCMDS`	Command Stack: last 5 commands; ▲▼ to browse, END LINE to run
`fVIEW`	Hold next key → shows its DEF KEY string
`gERRM`	Show last error/warning message
`fBACK`	Backspace (delete left) · in CALC: undo last operation
`f-CHAR` / `f-LINE`	Delete char under cursor / delete to end of line
`fI/R`	Toggle Insert / Replace cursor
◀ ▶ · `g`◀ `g`▶	Move cursor · jump to start / end of the 96-char line
▲ ▼	Previous / next line (FETCH neighbours, CAT entries, Command Stack)
`gCTRL`+key	Control character (CTRL-M = CR, CTRL-J = LF, CTRL-`g[` = ESC)
`ON`+`/`	INIT: 1 (system reset, memory kept) · 2 (self-test) · 3 (memory reset: clears main RAM; independent RAM survives)

Display: 22-character window on a 96-character line; ← → annunciators show the line extends. Typing aids: f+top-row keys type keywords (e.g. fS = DISP ).

Annunciators

f g shift pending · USER User keyboard · RAD radians · 0 1 2 3 4 user flags 0–4 set · BAT low battery · ((•)) alarm · PRGM program running · SUSP suspended · CALC CALC mode · AC reserved.

CALC Mode

fCALC toggles. Evaluates numeric expressions with intermediate results as you type — same variables, functions, precedence and user-defined single-line functions as BASIC. Assignments allowed (A=3*4).

SIN(30auto-supplies ")" — closing parens optional()implied result: value of the last evaluated expressionMAX(3,flashing "," reminds of missing arguments2+3*partial results shown as precedence allows

Key	In CALC mode
`END LINE`	Finish and evaluate
`RUN` / `fSST`	Show next intermediate step separately
`fBACK`	Backward execution: undo operands/operators one at a time
▲	Recall whole expression into Command Stack for editing; ⊲ shows it was already evaluated

Not available in CALC: strings, DTH$/HTD, multi-line user functions, statements other than assignment, program lines. Don't insert/remove modules while CALC mode is on (memory reset).

Program Lines & Syntax

10 DISP "HI" @ BEEP @ WAIT 1line number 1–9999; @ joins statements20 ! comment / 20 REM commentremarks (! also allowed after a statement)30 'AGAIN': X=X+1 @ IF X<5 THEN AGAINlabel = up to 8 letters/digits + colon; quotes added by the 7140 IF A>B THEN 100 ELSE DISP "NO"THEN/ELSE take a line, label or statement(s)LET A=1 · A=1 · A,B,C=0LET optional; multiple assignment

Keywords may be typed in lower case; the HP-71 uppercases keywords, file names and variable names. Strings keep case; quote with "…" or '…'.
Line length 96 chars. Program lines are kept sorted; enter in any order. Multi-statement lines save 2 bytes each.
Variables: a letter or letter+digit (A, X1); strings add $ (N$); arrays A(3), M(2,3) (max 2 dims). Numeric and string of the same name are distinct.
Files: name = 1–8 letters/digits, first a letter; optional device :MAIN, :PORT(n), :CARD. Reserved: ALL CARD KEYS TO INTO PCRD.
Numbers: 1.5E-3, -7; 12 significant digits, exponent ±499. Hex via HTD("FF"), DTH$(255).

Variables, Arrays & Strings

DIM A(10), B(3,4), N$[80]numeric arrays (default OPTION BASE 0), string max lengthREAL X, Y(5) · SHORT S(100) · INTEGER I,Jdeclare precision (also dimensions arrays)OPTION BASE 1lowest subscript 1 (default 0); must precede DIMDESTROY A, B$ · DESTROY ALLfree variables (ALL: every variable, incl. arrays)A$[3,5] · A$[4] · A$[3,3]="x"substring chars 3–5 · from 4 to end · replaceA$ & B$ · LEN(A$) · POS(A$,"x")concatenate · length · position (0 if absent)VAL("12.5") · STR$(2/3) · NUM("A") · CHR$(65)string↔number, char code↔charUPRC$(A$) · VER$ · A$="ab" & CHR$(13)uppercase · ROM version string · control chars

Type	Range	Storage
REAL (default)	±1E-499 … ±9.99999999999E499, 12 digits	8 bytes
SHORT	5 digits, ±9.9999E499	4 bytes
INTEGER	−99999 … +99999	3 bytes
String	default max 32 chars; DIM up to memory	len+2

Undeclared numeric variables are REAL scalars created on first use (value 0); strings default to "" with max length 32. Arrays are dimensioned implicitly to (10) / (10,10) on first use. Comparing strings uses character codes.

Operators & Precedence

Level	Operators (highest first)
1	( ) — innermost first
2	Functions: SIN, LOG, FACT, user FN…
3	^ (exponentiation)
4	unary −, NOT
5	* / % DIV
6	+ −
7	Relational: = # <> < <= > >= ?
8	AND
9	OR, EXOR

7 DIV 2 → 3 · 7 \ 2 → 3integer division (\ is the same operator)MOD(7,2) → 1 · RMD(-7,2) → -1modulo (sign of divisor) · remainder (sign of dividend)50 % 200 → 100x % y = x percent of yA=B vs IF A=B= assigns when the line can be read either wayX # Y · X <> Ynot equal (both forms)X ? Yunordered: 1 if either operand is NaNNOT A AND B → (NOT A) AND Blogical ops treat non-zero as true, return 1/0"ABC" < "ABD" → 1strings compare by character code

Same-level operators evaluate left to right. EXOR: exactly one true. Relational operators return 1 (true) or 0 (false).

Number Display & Rounding

STDminimum digits for full 12-digit accuracy (default)FIX 2 · SCI 4 · ENG 3fixed decimals · scientific · engineering (0–11 digits)OPTION ROUND NEAR|ZERO|POS|NEGrounding direction for inexact results (default NEAR)RESvalue of the last expression evaluatedEPS → 1E-499 · MAXREAL → 9.99999999999E499smallest / largest positive realMINREAL → 1E-499 · PI · INF · NANconstants (INF/NAN with DEFAULT EXTEND)RND · RANDOMIZE [seed]random 0≤r<1 · reseed (no arg: from clock)IP(-3.7)→-3 FP(-3.7)→-.7 INT(-3.7)→-4integer part · fraction · greatest integer ≤ xFLOOR = INT · CEIL(3.2)→4 · SGN · ABSrounding familyRED(x,y) → x-y*n, n=nearest int to x/yreduce (like MOD but rounds)

Numbers ≥ 1E12 in magnitude are always shown in exponential form. FIX/SCI/ENG digits are readable in flags −17…−20; format in flags −13/−14; rounding in flags −11/−12. Display formats do not change stored values (12-digit internal precision).

Math Exceptions & IEEE

Exception	Flag	Name	Examples
Invalid operation	−8	IVL	ACOS(2), LOG(-23), (-14)^(-1/3)
Division by zero	−7	DVZ	187/0, TAN(90)
Overflow	−6	OVF	FACT(254), 10*1E499
Underflow	−5	UNF	EXP(-1149), 1/3E499
Inexact result	−4	INX	1/3, 1+1E-50

DEFAULT ON(reset state) DVZ/OVF/UNF → warning + default value; IVL stopsDEFAULT OFFany exception except INX is an error (use ON ERROR)DEFAULT EXTENDIEEE defaults: Inf, -Inf, NaN; math continuesTRAP(DVZ,2) · TRAP(-7)set trap for a flag: 0 error · 1 default value · 2 IEEE value; no 2nd arg → readCFLAG MATH · CFLAG -8clear all / one math-exception flagCLASS(X)category of X: 1 zero, 2 denormalised, 3 normalised… ±sign; NaN/Inf classesX ? Y · INF · NANunordered test · IEEE constants (with DEFAULT EXTEND)

ERRN	Warning (DEFAULT ON)	Default value
1 UNF	underflow	0
2 OVF	overflow	±99999 INTEGER · ±9.9999E499 SHORT · ±9.99999999999E499 REAL
3 DVZ	EXPONENT(0)	−9.99999999999E499
4 DVZ	TAN of odd multiple of 90°	±9.99999999999E499
5 DVZ	0 ^ negative	±9.99999999999E499
6	0 ^ 0	1
12 DVZ	LN(0)	−9.99999999999E499

Branching, Loops & Conditionals

GOTO 100 · GOTO DONEline or labelGOSUB 500 … RETURN · POPsubroutine; POP discards one pending RETURNON N GOTO 10,20,LAB · ON N GOSUB …N rounded → 1st, 2nd… targetON N RESTORE 100,200sets DATA pointer by NIF X<0 THEN X=-X @ Y=1 ELSE Y=0statements after THEN/ELSE run only on that branchIF A THEN 100THEN line-number = GOTOFOR I=1 TO 10 STEP 2 … NEXT Iloop; NEXT var optional; body skipped if start beyond limitWAIT 2.5 · PAUSE · STOP · END · END ALLdelay · suspend (CONT resumes) · halt · end · end all subprograms tooON TIMER #1,30 GOTO 900 · OFF TIMER #13 timers, 0.1 – 134 217 727 s; retriggers each intervalON TIMER #2,15 GOSUB 100RETURN re-arms; timers can wake a switched-off HP-71BYE · OFFturn off (a program with a timer resumes on wake-up)

GOTO/GOSUB cannot branch into a subprogram or user function. Timers are local to the program/subprogram that set them. Nested GOSUBs limited only by memory.

Subprograms & User Functions

CALL AREA(R, A) ! in current filecall subprogram; parameters by referenceCALL AREA((R), A) IN GEOM(R) passes by value; IN file = other fileSUB AREA(X, Y) @ Y=PI*X*X @ END SUBsubprogram; own variables, flags & files sharedSUB SHOW(A(,), N$) … END SUBarray (,) and string parametersDEF FNC(F)=(F-32)*5/9single-line numeric functionDEF FNR$(S$)=S$[LEN(S$)]&S$[1,LEN(S$)-1]string functionDEF FNF(N) @ IF N<2 THEN FNF=1 ELSE FNF=N*FNF(N-1) @ END DEFmulti-line: assign to name, END DEF returnsDISP FNC(212) · X=FNF(5)use like built-ins (single-line ones also in CALC mode)

SUB…END SUB blocks live in program files (after the main program or in a file of their own). CALL name searches the current file, then all files. RUN starts at the first line, so a file may be all subprograms.
Subprogram variables are local; only parameters, files, flags, and DATA are shared. END SUB / END returns to the caller.
Recursion allowed (memory limited). END ALL terminates the whole chain of subprograms.

Errors & Debugging

ON ERROR GOTO 900 · ON ERROR GOSUB 900trap run-time errors; GOSUB returns to the failing statementOFF ERRORrestore normal error haltERRN · ERRL · ERRM$last error number · line · message textTRACE FLOW · TRACE VARS · TRACE VARS A,B$ · TRACE OFFshow branches / assignments while runningCONT · CONT 120 · RUN 120 · RUN FILE,LABresume · from a line · run from line/labelSFLAG -1suppress most warning messagesBEEP OFF · SFLAG -2silence beeper (flag −2)

Message form	Meaning
`ERR:Invalid Expr`	syntax error from the keyboard
`ERR L30:String Ovfl`	run-time error at line 30 (program suspended)
`WRN L30:…`	warning; execution continues
`Line Too Long`, `Missing Param`, `Data Type`…	common messages — full list in the Reference Manual

gERRM or ERRM$ redisplays the last message. Errors set ERRN/ERRL; a suspended program shows SUSP — fix and CONT, or SST through it. Math-exception warnings 1–12 are listed in "Math Exceptions".

Flags

SFLAG 3 · CFLAG 3 · FLAG(3)set · clear · test (1/0)IF FLAG(-10) THEN …system flags are negativeCFLAG ALL · CFLAG MATHclear all user flags 0–63 · clear −4…−8SFLAG -25 · RESETloud beeper · reset system flags to defaults

Flag	Meaning (set = …)
0 – 63	User flags; 0–4 have annunciators
−1	Suppress warning messages
−2 / −25	Beeper off / loud
−3	Continuous on (no 10-min auto-off)
−4…−8	INX UNF OVF DVZ IVL math exceptions
−9	User keyboard active
−10	Radians (RAD annunciator)
−11,−12	Rounding: 00 NEAR · 01 ZERO · 10 POS · 11 NEG
−13,−14	Format: 00 STD · 10 FIX · 01 SCI · 11 ENG
−15	Lowercase keyboard
−16	OPTION BASE 1
−17…−20	Digits shown (binary, −17 = bit 0)
−26	BASIC prompt suppressed
−46	EXACT executed (read-only)
−57 −60…−64	AC · alarm · BAT · PRGM · SUSP · CALC annunciators (read-only)

−1…−32 may be set/cleared/tested; −33…−64 test only. All flags are global (visible in subprograms).

Input & the Keyboard

INPUT A, B$prompts "?"; items separated by commas; expressions allowedINPUT "NAME, AGE: "; N$, Acustom prompt (quoted string; can't be overwritten)INPUT "N? ","10"; Ndefault string appears in the display for editingLINPUT "TEXT? "; L$whole line into one string (commas, quotes kept)K$=KEY$oldest key from the 15-key buffer ("" if none); same names as DEF KEYKEYDOWN · KEYDOWN("Q") · KEYDOWN("#43")any key down? · specific key (unshifted only)PUT "RUN"&CHR$(13) · PUT "#43"push keystrokes into the key bufferDISP$readable characters currently in the display (max 96)

User keys

DEF KEY "fS","DISP TIME$";typing aid (";") — string only displayedDEF KEY "gC","RUN CLOCK":execute-only (":") — runs directly, display ignoredDEF KEY "A","STD @ FIX 2"display-then-execute (no suffix)DEF KEY "#43" · DEF KEY "K"key by number (1–56, f: 57–112, g: 113–168) · cancelFETCH KEY "gC" · KEYDEF$("gC")edit definition · read assigned stringUSER · USER ON · USER OFFtoggle / set the User keyboard (flag −9)LIST KEYS · PURGE KEYS · MERGE KEYFILEdefinitions live in the "keys" fileCOPY KEYS TO K1 · COPY K1 TO KEYSsave / restore key sets

Output & Formatting

DISP A; B$, C";" no space (numbers get sign/space), "," next 21-col fieldDISP "X=";X; · PRINT TAB(10);Atrailing ; suppresses end-of-line · TABPRINT …to printer (or display when no printer is assigned)DISP USING "DDD.DD,4X,5A"; N, S$format string inlinePRINT USING 100; A, B · 100 IMAGE 2(8X,6D)/format on an IMAGE lineF$="SDDD.DD" @ DISP USING F$; Vstring variable formatDELAY 0.5,0.1 · DELAY 8line rate (s), scroll rate; ≥ 8 = infinite (wait)WIDTH 22 · PWIDTH 80 · ENDLINE CHR$(13)&CHR$(10)line lengths 0–96 · end-of-line string (≤3 chars)WINDOW 5,18 · WINDOW 1protect display columns outside 5–18 · unprotectCONTRAST 9 · BEEP 440,.5 · BEEP0–15 · Hz, seconds (default 500 Hz, .25 s)GDISP D$ · D$=GDISP$132-column dot pattern out / in (1 char per column)CHARSET CHR$(64)&… · CHARSET$define chars 128… (6 bytes per char) · read set

IMAGE field specifiers

Spec	Meaning
D	digit (leading zeros as blanks)
Z	digit with leading zeros
*	digit, leading asterisks
S	sign + or −
M	− or blank
.	decimal point
R	comma as radix
C	digit separator ,
E	exponent field
K	compact (like STD, no padding)
A	character
X	blank
"text"	literal
/	end of line
#	suppress end of line
B	byte: char with the given code
n(…)	repeat group n times
,	field separator

Symbol list per the Reference Manual's IMAGE entry (the Owner's Manual defers to it). A format string is reused when the list has more items than fields. Numeric field ↔ numeric item, else error. Escape sequences (ESC = CHR$(27)): ESC< cursor off · ESC> on · ESC E clear · ESC N/R insert/replace · ESC %cn cursor to column CODE(c) · ESC C/D right/left · ESC K clear to end · ESC O delete char. Text written while the cursor is off is a protected field.

Files & Memory

File type	What
BASIC	program (EDIT/RUN)
TEXT	LIF1 text records (TRANSFORM, HP-IL transfer)
DATA	random/sequential records (CREATE DATA)
SDATA	8-byte numbers, HP-41 compatible
KEY	key definitions ("keys" = current)
BIN / LEX	binary program / language extension (keywords)

EDIT PROG · EDIT · NAME NEWNAMEmake current (create if new) · edit workfile · name itCAT · CAT ALL · CAT PROG · CAT :PORT(1) · CAT$(2)catalog: current file · all · one · device · nth entryCOPY A TO B · COPY A TO :PORT(0) · COPY :CARD · COPY A TO CARDduplicate (dest. must not exist)RENAME A TO B · PURGE A · PURGE KEYSrename · deleteMERGE SUBS · MERGE SUBS,100,200append lines of another BASIC file (line range) into currentSECURE F · UNSECURE F · PRIVATE Fno modify/purge · undo · irreversible: run only, no list/copy/editPROTECT / UNPROTECTcard write-protection (HP 82400A)TRANSFORM PROG INTO TEXT PTXT · TRANSFORM PTXT INTO BASICprogram ↔ text fileMEM · MEM(0) · SHOW PORT · SHOW PORT 0free bytes (main RAM / port) · port sizes & type (1 RAM 2 ROM)FREE PORT(0.02) · CLAIM PORT(0)make 4K unit independent RAM (survives INIT: 3) · reclaim (clears it)ADDR$("PROG") · PEEK$("2F400",8) · POKE "2F400","0F"file address · read/write nibbles as hex strings

Devices: :MAIN, :PORT (all ports), :PORT(n) n = 0–5 (5 = card reader port), :CARD, :PCRD (private card). Search order without a device: main RAM, then ports 0,1,2… Port 0 = internal 16 K in four 4 K units (0, .01, .02, .03). CAT columns: NAME S TYPE LEN DATE TIME PORT (S: P private, S secure).

Data: DATA/READ & Data Files

100 DATA 1, 2.5, "text", ABCconstants in program lines (unquoted strings OK)READ A, B, S$ · RESTORE · RESTORE 200sequential read · reset pointer (to a line)CREATE DATA DF, 50, 32DATA file: 50 records of 32 bytes (defaults: 1 record, 256 bytes)CREATE TEXT TF · CREATE SDATA SF, 100text file · SDATA (100 8-byte numbers)ASSIGN #1 TO DF · ASSIGN #1 TO DF:PORT(1) · ASSIGN #1 TO *open channel 1–255 · closePRINT #1; A, B$, M(,)sequential write; whole array with (,)PRINT #1,5; X · READ #1,5; Xrandom access: record 5READ #1; A, B$ · RESTORE #1 · RESTORE #1,3sequential read · rewind · to record 3IF … THEN … ON ERROR GOTO EOFend of file gives an error → trap itCALL SUB1(#1) · SUB SUB1(#C)pass an open channel to a subprogram

DATA files store numbers (8 bytes) and strings (length+text) in records; an item that doesn't fit a record spills to the next in sequential mode but errors in random mode. TEXT files are read/written a line (record) at a time. Closing: ASSIGN # TO * or program END.

Editing & Running Programs

EDIT PROGcreate/select current file — the PRGM lines you type go here10 DISP "HELLO"type line number + statements, END LINEAUTO · AUTO 100,5auto line numbers (start, step; default 10,10); ATTN endsFETCH 30 · FETCH LAB · ▲ ▼bring a line to the display for editing; step throughLIST · LIST 100,200 · PLISTlist (display, paced by DELAY) · to printerDELETE 30 · DELETE 30,90 · DELETE ALLremove linesRENUMBER · RENUMBER 100,10 · RENUMBER 1000,10,500,600renumber (new start, step, old first, old last)RUN · RUN PROG · RUN PROG,LAB · RUN 200run current / named file, from a line or labelCALL PROG · CHAIN PROG:CARDrun as subprogram · purge current, load & run nextCONT · f-SST · ATTNcontinue · single-step · suspendCOPY TO PROG · DELETE ALLsave the workfile under a name · clear workfileSECURE PROG · PRIVATE PROGprotect before distributing

workfile is the unnamed default file (NAME gives it a name). Only one current file; RUN filename makes it current. BIN files run with RUN/CALL but can't be listed; LEX files add keywords and just need to be in memory. TRACE FLOW/VARS for debugging.

Clock, Calendar & Timers

SETDATE "85/03/07" · SETDATE 85066 · SETDATE "1985/03/07"YY/MM/DD or YYDDD (day of year)DATE → 85066 · DATE$ → "85/03/07"numeric YYDDD · stringSETTIME "08:15:00" · SETTIME 8*3600+15*6024-hour string or seconds since midnightTIME → 29700 · TIME$ → "08:15:00"seconds since midnight · stringADJABS -3600 · ADJABS "-01:00:00"shift clock, no speed correction (time zones)ADJUST 43 · ADJUST "00:01:00"shift and accumulate a speed-correction (±100 h)EXACTmark "clock is exact now"; applies accumulated correction (flag −46)AF(0.5) · AFset / read speed adjustment factor directlyRESET CLOCKclear speed correction, keep timeON TIMER #1,60 GOSUB TICKsee Branching — 3 timers, wake from OFF

Set the clock with SETTIME after a memory reset, then EXACT; later use SETTIME/ADJUST to correct drift and EXACT again to teach the crystal correction. Calendar range 0000–9999 (Gregorian from 1582/1752).

Statistics

STAT S(3) · STAT Screate/select current statistical array for 3 variables (max 15) · reselectCLSTATclear (zero) the current statistical arrayADD 6.4, 3.85, 3.6 · DROP 6.4, 3.85, 3.6add / remove a data point (one value per variable)TOTAL(2) · TOTAL(0) · MEAN(1) · SDEV(3)sum of var 2 · number of points · mean · sample std. dev.CORR(1,2)sample correlation of variables 1 and 2LR 2,1 · LR 2,1,A,Blinear regression of var 2 on var 1; intercept→A, slope→BPREDV(X)predicted dependent value at X for the current LR model

The array holds only summary statistics (sums, sums of squares, cross products), always base 0 and REAL. Default variable number is 1. Fit other curves by transforming data (e.g. ADD X, LN(Y) for exponential fits).

Idioms

10 DESTROY ALL @ OPTION BASE 1 @ STDclean start of a program20 DELAY 0,0fastest display, no waiting30 ON ERROR GOSUB 900central error handler40 INPUT "N? ",STR$(N); Nre-prompt with previous value as default50 K$=KEY$ @ IF K$="" THEN 50wait for a key60 IF UPRC$(K$)="Q" THEN ENDquit on Q (ATTN itself suspends the program)70 DISP "Working…"; @ … @ DISPprogress on one line80 T=TIME @ … @ DISP TIME-T;"s"timing (seconds)90 A$=DTH$(HTD(A$)+1)hex arithmetic100 IF FLAG(-10) THEN RADIANS ELSE DEGREESpreserve angle mode110 X=RND*(H-L)+Lrandom real in [L,H)120 SFLAG -1 @ … @ CFLAG -1quiet sectionDEF KEY "gR","RUN":one-key run from the User keyboardSTARTUP "RUN MENU"command executed at every power-onLOCK "SECRET"lock the keyboard until the password is typed

Emu71 menu	Use
File → New / Open / Save (.e71)	Emulator state = the calculator's whole memory. Save before quitting (or enable Settings → "Automatically Save Files On Exit").
Edit → Port Configuration…	Plug modules: RAM (4/32 K…), ROMs from `run/` (MATHROM.BIN, Hpilrom.bin, FORTHROM.BIN/HRDFORTH.BIN), HP-IL interface. Then `SHOW PORT` / `CAT :PORT(n)` on the 71.
Edit → Copy Stack / Paste Stack	Copy the display text to the clipboard · paste clipboard text into the command line (BASIC mode). Handy for single lines.
Edit → Reset Calculator · Backup	CPU reset (then INIT: 1/2/3 as on the real machine) · snapshot / restore state.
File → Settings → Authentic Calculator Speed	Uncheck for maximum speed (needed for fast macro replay).
Tools → Macro → Record / Play / Stop / Settings	Keyboard macro recorder — the way to "type" a whole program file into the 71.
View → Change KML Script	Other skins incl. module-overlay backgrounds (kml-overlays).

HP-71B BASIC Reference Programmer's guide · 249 keyword entries grouped by function · from the HP-71 Owner's Manual

HP-71B Programmer's Reference

Annunciators

User keys

IMAGE field specifiers

Keyword Reference

Files

Lines

Run

Branch

Stop & wait

Subprograms & functions

Timers

Errors

Variables

Ports

Arithmetic

Relational

Logical

Parts & rounding

Powers & roots

Random & constants

Conversions

Exceptions

Functions

Mode

Data

Results

Functions

Display & print

Keyboard input

Data statements & files

Formats

Catalog & copy

Protection

Memory

Read

Set & adjust

User keys

Display & system

Flags

Modes

Emu71 Emulator Notes

Editing programs offline and loading them