Original Blog Entry: 9th Part: "Nostalgia" "Old" Basic Language interpreters, Commodore 64 Basic Interpreter # 1.

LANTERN — Wed, 13 Apr 2011 17:27:04 GMT

Numbers and strings can also be printed close or near to each other.

The Semicolon ; is used between data.

1 PRINT 1;2;3;7;23;19;874

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

1 PRINT 1;2;3;7;23;19;874

RUN

1 2 3 7 23 19 874

READY.

--------

The computer prints 2 spaces between the numbers.

-------

To print 2 Strings:

10 PRINT HOT ; DOG

---

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 PRINT HOT ; DOG

RUN

HOTDOG

READY.

In that way no spaces were printed between HOT and DOG.

-----------

10 PRINT HOT ; DOG

-------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 PRINT HOT ; DOG

RUN

HOT DOG

READY.

-------------------

To print 4 numeric variables:

10 W=10:X=15:Y=20:Z=25

20 PRINT W;X;Y;Z

---------------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 W=10:X=15:Y=20:Z=25

20 PRINT W;X;Y;Z

RUN

10 15 20 25

READY.

-----------------------

To PRINT 3 String Variables:

10 A$= TICK :B$= TOCK :C$=

20 PRINT A$;C$;B$

TheC$ is also a string.

Numbers and strings can also be mixed.

----------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 A$= TICK :B$= TOCK :C$=

20 PRINT A$;C$;B$

RUN

TICK TOCK

READY.

------------------

10 X=2*3

20 PRINT THE ANSWER= ;X

-------------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 X=2*3

20 PRINT THE ANSWER= ;X

RUN

THE ANSWER= 6

READY.

--------------

10 PRINT 10;20;30;40

20 PRINT 100;200;300;400

30 PRINT 1000;2000;3000;4000

-------------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 PRINT 10;20;30;40

20 PRINT 100;200;300;400

30 PRINT 1000;2000;3000;4000

RUN

10 20 30 40

100 200 300 400

1000 2000 3000 4000

READY.

In this way data doesn't line up right as when you use standard columns.

---------------------

--------------------

To print data with spaces you can use the SPC keyword.

SPC(X) the (X) stand for the number of spaces.

For example:

10 PRINT A SPC(6) B

It should skip 6 spaces between A and B.

--------------------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 PRINT A SPC(6) B

RUN

A B

READY.

------------------

Variables can be used to represent the spaces:

10 S1=7

20 S2=11

30 PRINT A SPC(S1) B SPC(S2) C

-------------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 S1=7

20 S2=11

30 PRINT A SPC(S1) B SPC(S2) C

RUN

A B C

READY.

--------------

The TAB keyword.

TAB(X), X = 0 up to 255

----------

10 PRINT TAB(20) ABC TAB(30) DEF

----------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 PRINT TAB(20) ABC TAB(30) DEF

RUN

ABC DEF

READY.

-----------------

Numeric variables can also be used:

10 A1=20

11 A2=30

12 PRINT TAB(A1) 200 TAB(A2) BANANAS

-------------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

10 A1=20

11 A2=30

12 PRINT TAB(A1) 200 TAB(A2) BANANAS

RUN

200 BANANAS

READY.

--------------------------

Printing reverse characters is just printing with reverse colors, the font and the background of the characters will be reversed that is their colors only.

That is for an emulator or for a Comodore 64, so I will skip on that here at least for now.

-----------------

On a Commodore there are cursor control keys CRSR and they can also be used with the PRINT command, but here on a Pc like this that casn't be done other than with an emulator so I have to skip on that.

------------------

On an emulator and on the C-64 there are other ways in which the key words can be entered like using ? for the PRINT keyword, let us see if that will work here with this interpreter or not:

1 ? Hello

-------

**** COMMODORE 64 BASIC V2 ****

64K RAM SYSTEM 38911 BASIC BYTES FREE

READY.

1 ? Hello

RUN

Hello

READY.

--------

It worked so that can be used.

I think that all the keywords have such things, for more info look at the books that you downloaded from my links on the C-64 guides maybe at the very end of them they are there.

Such things do save on having to do a lot of typing, long ago when I took a look at Commodore basic and was typing a lot of programs' lines by hand I was using them.

--------------

So here ? = PRINT

==============

Well that is it for this post.

-----------------

Are we learning some yet?

Programming is so hard and complicated and takes so very long to code and to think how to code in order to do what you want done and it might take a lot of Math knowledge to do things that might be of some use, that it might not be a thing that many or most of us want or should do.

And not because a person knows what the keywords do, that doesn't mean that a person can make programs with them, things are complicated and convoluted.

As Andrew said about WinHunter (His Lottery Program): Not For The Faint Of Heart .

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