NEW
NEW is a BASIC command to erase the current program and variables.
Availability | Present in all original versions of BBC BASIC. | |
Syntax | BASIC I-V | NEW
|
Token (hex) | BASIC I-IV | CA (command)
|
BASIC V | C7 97 (command)
| |
Description | BASIC I-V | Writes an empty program at PAGE , CLEAR s the BASIC heap and resets TOP , VARTOP and the DATA pointer.
|
Associated keywords | OLD
|
Description
NEW
erases the BASIC program currently in memory, as well as all non-resident variables, arrays and memory blocks. As a command it cannot be executed within a program.
NEW
does not affect the resident integer variables A%
to Z%
and @%
.
If NEW
has been entered by mistake, the program can be recovered with OLD
, provided no new programs have been LOAD
ed, lines entered or variables declared. The old variables, however, are permanently lost.
If there is no valid program at PAGE
, the user must enter NEW
before trying to type in a listing, otherwise the computer may crash searching for the end of the program.
The command writes the end-of-program marker, &0D &FF (6502/32000/ARM), &00, &FF, &FF (Z80/80x86/PDP), to memory at PAGE
, sets TOP
= PAGE
+ 2 (6502/32000/ARM) or PAGE
+3 (Z80/80x86/PDP) and the DATA
pointer to PAGE
. It then does a CLEAR
, resetting the heap head pointers and setting VARTOP = LOMEM
.
-- beardo 19:26, 20 March 2007 (UTC)