Corrections to Apple Basic User Manual

As I work with Apple BASIC I noticed a few errors and omissions on the manual. I wrote them down in the hope that they may be useful to someone else. Maybe Apple will issue a revised version :-)

The latest version can be found here but for convenience (and so it is searchable by Google) I'll paste my current version here.

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This document lists some corrections to errors in the document "Preliminary Apple Basic Users Manual' October 1976. It also lists some notes on features that are non-obvious or of interest.

Title Page:

Note: The woodcut image of Sir Issac Newton sitting under an Apple Tree was the original Apple Computer Company Logo drawn by Ronald Wayne, the third employee of Apple.

Note: The address listed is no longer the headquarters of Apple Computer :-)

Second page:

Error: The word "likley" is misspelled (It is ironic that this is the page that says the manual may contain errors and asks users to send in corrections).

Page 1:

Note: An alternative way to get to the monitor from BASIC is to execute the command "CALL -256".

Page 2:

Note: The instructions for saving BASIC programs on tape assume LOMEM and HIMEM have their default values. If not, you need to adjust the command listed in step 3 accordingly.

Page 4:

Note: A quirk of Apple BASIC is that the number -32768, which is a valid 32 bit signed value, is not accepted. I don't think this was an oversight As Woz was an excellent programmer and had designed calculators in his career. I suspect it was to allow the the "*** >32767 ERR" message to be used for all overflow errors. We'll come across this issue later.

Page 6:

Error: Under point 3, if a string is not dimensioned it's length is taken to be one, not zero.

Page 7:

Error: The word "destingation" should be "destination" (in two places).

Page 8:

Note: Unlike expressions, string comparison using "<>" is not supported, only "#".

Page 10:

Error: The statement that changing LOMEM or HIMEM destroys the current user program is not correct. The program will still exist but may not run reliably. You should execute a SCR command before setting LOMEM or HIMEM. There is also no check that the values for LOMEM and HIMEM are valid.

Note: There is no way to suppress the question mark prompt in INPUT statements.

Page 12:

Note: The target of a GOTO or GOSUB can be an expression. This feature is not supported in most other versions of BASIC.

Note: In a remark statement like

10 REM A COMMENT : GOTO 100

Apple BASIC considers the whole line to be a comment.

Page 13:

Note: An error is reported if the last line executed in a program was not an END statement.

Note: Due to the quirk of not supporting the number -32768, you cannot use this address ($8000 in hex) with PEEK, POKE, or CALL.