BAS100.THD  --- Copyright 1987 by Phil Wheeler

An original compilation of Compuserve Model 100 Forum messages for use by
Forum members only.

This thread starts with a question which may never have been properly
interpretted by the answerers (including myself).  But one the last message
gives some interesting information on the structure of tokenized Basic (BA)
files in Model 100 (etal) memory.

Message range: 151419 to 151594
Dates: 7/1/87 to 7/3/87


Sb: #m100 basic compressed
Fm: Dick Monahan 73240,1535
To: all

Is there a DL file explaining the extra bytes between statements in a .BA file?
I want to edit programs on my AT and download them to m100.  I know all the
keywords, but the extras don't make sense.


Fm: Tony Anderson 76703,4062
To: Dick Monahan 73240,1535

No, there is no file explaining that.  The Model 100 family's BASIC will work
with no extra spaces in the statements.  There is, in fact, several programs
that are designed to remove them, and all non-executing statements, such as
REMarks. You can remove the spaces at any time, or put more in, it makes no
difference. Well, very little, anyway.

If that's not the thrust of your question, could you clarify what you mean by
"extra bytes"?  What extra bytes?


#: 151425 S8/Tech/Programming
    01-Jul-87  20:33:33
Sb: #151419-m100 basic compressed
Fm: Phil Wheeler 71266,125
To: Dick Monahan 73240,1535

It is fairly easy to write programs for PC/GW BAsic which will run on the M100
with only minor syntax changes.  And you can write ASCII format Basic programs
on ANY machine with an ASCII text editor and upload them to the Model 100. I've
done both -- and even written M100 Basic programs that will run with minor (or
no) changes on a PC.

But -- don't understand the "extra bytes" reference.  Please clarify, with an
example if possible.


#: 151594 S8/Tech/Programming
    03-Jul-87  20:37:19
Sb: #151419-m100 basic compressed
Fm: Scott Hibbard 70536,674
To: Dick Monahan 73240,1535

     I think your talking about the pointers in a .BA file.  Picture worth
thousand words:


 | A2L | A2H | LNL | LNH | Line contents ..... | 00 | A3L | A3H ...
 | <---------- 1st line --------------------------> | <- 2nd line -

Each line starts with a 2 byte word that is the address for the beginning of
the NEXT line.  In this example, A2L & A2H will contain the address (point to)
A3L.  This is used by BASIC to quickly find a line.  The next two bytes (LNL &
LNH) contain THIS line's number (in good old bass ackwards Intel format of
course).  The tokenized line contents follow, ended by a null byte (00h).
After the last line in the program will be 2 null bytes.

An example of a 2 line program that is the FIRST BASIC program in memory (&
therefore starts at 8001h):
        10 PRINT "Hello
        20 END


 Line 10: (8001h) |0D|80|0A|00|A3|22|68|65|6C|6C|6F|00|
 Line 20: (800Dh) |13|80|14|00|80|00|
 Ending:  (8013h) |00|00|