ER
| BASIC keyword | |
| Keyword: | ER |
| Abbreviation: | - |
| Type: | system variable |
| Token code: | None |
| Handling routine in BASIC ROM: |
?–? ?–? |
| List of all BASIC keywords | |
Remark: This article describes the BASIC system variable ER in Commodore BASIC V3.5 or higher.
Type: System Variable General Programming-Syntax: ER
ER returns the number of the BASIC interpreter's last error occurred.
This variable is read-only. An assignment to this variable stops the program execution with ?SYNTAX ERROR.
After BASIC start (cold or warm start) or a program ends without any error, ER contains the value -1.
The commands RUN, CLR and RESUME resets the value to -1 also.
Depending on the machine there are different possible number ranges for the error number. The C16 has a range from 1 to 36 and the C128 up to 41 messages. In comparison, the VIC20 and C64 have only 30 messages, but they do not have the option to print them.
Examples[edit | edit source]
PRINT ER
Result (after a successful program run or right after a reset:
-1
The use of variables in an error handling routine:
10 TRAP 1000 20 PINT "START..." 30 PRINT "END." 40 END 1000 REM ERROR LOOKUP 1010 PRINT "ERROR " ERR$(ER) " IN LINE" EL 1020 IF ER=11 THEN END : END BY SYNTAX ERROR 1030 RESUME NEXT : REM JUST CONTINUE...
It intercepts errors that occur, but in the event of syntax errors, execution ends, otherwise it continues with the next command.
See also[edit | edit source]
ABS | ASC | ATN | AUTO | BACKUP | BOX | CHAR | CHR$ | CIRCLE | CLOSE | CLR | CMD | COLLECT | COLOR | CONT | COPY | COS | DATA | DEC | DEF | DELETE | DIM | DIRECTORY | DLOAD | DO | DRAW | DS | DS$ | DSAVE | END | EL | ELSE | ER | ERR$ | EXIT | EXP | FN | FOR | FRE | GET | GET# | GETKEY | GOSUB | GOTO | GRAPHIC | GSHAPE | HEADER | HELP | HEX$ | IF | INPUT | INPUT# | INSTR | INT | JOY | KEY | LEFT$ | LEN | LET | LIST | LOAD | LOCATE | LOG | LOOP | MID$ | MONITOR | NEW | NEXT | ON | OPEN | PAINT | PEEK | POKE | POS | PRINT | PRINT USING | PRINT# | PUDEF | RCLR | RDOT | READ | REM | RENAME | RENUMBER | RESTORE | RESUME | RETURN | RGR | RIGHT$ | RLUM | RND | RUN | SAVE | SCALE | SCNCLR | SCRATCH | SGN | SIN | SOUND | SPC | SQR | SSHAPE | STOP | STR$ | SYS | TAB | TAN | TRAP | TROFF | TRON | UNTIL | USR | VAL | VERIFY | VOL | WHILE | WAIT
ABS | AND | APPEND | ASC | ATN | AUTO | BACKUP | BANK | BEGIN | BEND | BLOAD | BOOT | BOX | BSAVE | BUMP | CATALOG | CHAR | CHR$ | CIRCLE | CLOSE | CLR | CMD | COLLECT | COLLISION | COLOR | CONCAT | CONT | COPY | COS | DATA | DCLEAR | DCLOSE | DEC | DEF FN | DELETE | DIM | DIRECTORY | DLOAD | DO | DOPEN | DRAW | DS | DS$ | DSAVE | DVERIFY | EL | ELSE | END | ENVELOPE | ER | ERR$ | EXIT | EXP | FAST | FETCH | FILTER | FN | FOR | FRE | GET | GET# | GETKEY | GO64 | GOSUB | GOTO | GRAPHIC | GSHAPE | HEADER | HELP | HEX$ | IF | INPUT | INPUT# | INSTR | INT | JOY | KEY | LEFT$ | LEN | LET | LIST | LOAD | LOCATE | LOG | LOOP | MID$ | MONITOR | MOVSPR | NEW | NEXT | NOT | (OFF) | ON | OPEN | OR | PAINT | PEEK | PEN | (PI) | PLAY | POINTER | POKE | POS | POT | PRINT | PRINT USING | PRINT# | PUDEF | (QUIT) | RCLR | RDOT | READ | RECORD | REM | RENAME | RENUMBER | RESTORE | RESUME | RETURN | RGR | RIGHT$ | RND | RREG | RSPCOLOR | RSPPOS | RSPRITE | RUN | RWINDOW | SAVE | SCALE | SCNCLR | SCRATCH | SGN | SIN | SLEEP | SLOW | SOUND | SPC( | SPRCOLOR | SPRDEF | SPRITE | SPRSAV | SQR | SSHAPE | ST | STASH | STEP | STOP | STR$ | SWAP | SYS | TAB( | TAN | TEMPO | THEN | TI | TI$ | TO | TRAP | TROFF | TRON | USR | VAL | VERIFY | VOL | WAIT | WHILE | WINDOW | WIDTH | XOR
