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Who wrote this stuff?
This trivia was originally written by Jim Brain as part of the now long defunct C= Hacking Magazine, but happily Jim has kindly agreed to let me reproduce it in HTML-ized format for retro computing fans everywhere.

If you are interested in seeing the Commodore Trivia digests in their original form, take a look at this website.

For those who are interested, these pages were generated from the original text files using Perl and Velocity (and a nice template originally found here)

 
TRIVIA 13A

$0C0)
	The early 1541 drives used a mechanism developed by ______.  Name
        the company.

	Alps.

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$0C1)
	On later models, Commodore subsequently changed manufacturers
        for the 1541 drive mechanism.  Name the new manufacturer.

	Newtronics.

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$0C2)
	What is the most obvious difference(s).  (Only one difference is
        necessary)

	Alps:        push-type latch, round LED.
        Newtronics:  lever-type latch, rectangular LED.
					    

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$0C3)
	On Commodore BASIC V2.0, what answer does the following give:
        PRINT (SQR(9)=3)

	0.  According to Commodore BASIC, the answer should be -1, which
        is the BASIC value of TRUE.  However, the above equation is NOT
        true.  Doing PRINT SQR(9) yields 3, but doing PRINT (SQR(9)-3)
        yields 9.31322575E-10 (C64).  This anomaly can be attributed to
        roundoff errors in the floating point math routines in Commodore BASIC.

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$0C4)
	In Commodore BASIC (Any version) what does B equal after the following
        runs: C=0:B=C=0 
           

	B = -1.  The second statement is the one to look at.  The second
        equals sign is treated as a comparison, while the first is treated
        as a assignment.  B gets set to the outcome of the comparison, which
        is TRUE (-1).

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$0C5)
	The first PET cassette decks were actually _______ brand cassette 
        players, modified for the PET computers.  Name the comapny.

	Sanyo. Specifically, Model M1540A.  What a model number!

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$0C6)
	In Commodore BASIC (Any version), what happens if the following
        program is run:
        
        10 J=0
        20 IF J=0 GO TO 40
        30 PRINT "J<>0"
        40 PRINT "J=0"

	On BASIC 2.0 or greater:
	
	?SYNTAX  ERROR IN 20
        READY.
        
        On BASIC 1.0:  (found on the PET 2001 series)
        
        J=0
        READY.
        BASIC 1.0 totally ignored spaces, so line 20 became "IFJ=0GOTO40".
        That statement would be correctly parsed, since it contains the "GOTO"
        keyword.  				    
        
        However, on BASIC 2.0 or greater, spaces weren't ignored so completely,
        and the "TO" in "GO TO" would be tokenized separately, so some code was
        added to BASIC to check to "GO".  As the code that accepts GOTO as a special
        case for THEN after an IF statement wasn't patched this way, the above fails,
        because GO is not a valid keyword after IF.  The statement SHOULD
        work correctly, but does not because of this failure to fix the IF
        command parsing.
        
        On BASIC 2.0 or greater, substituting the following line for line
        20 will cause the program to work:
        
        20 IF J=0 THEN GO TO 40

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$0C7)
	In question $068, we learned how Jack Tramiel first happened upon the
        name "COMMODORE".  According to the story, though, in what country
        was he in when he first saw it?

	Germany.  

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$0C8)
	On the Commodore user port connector, how many edge contacts are
        there?

	24.  Two rows of 12 contacts each.

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$0C9)
	On most Commodore computers, a logical BASIC screen line can contain
        up to 80 characters.  On what Commodore computer(s) is this not true?

	According to Commodore documentation, a _physical_ screen line is 
        defined as one screen line of characters.  A _logical_ screen line is 
        defined as how many _physical_ lines can be chained together to 
        create a valid BASIC program line.  
        With that in mind, most Commodore computers chose a _logical_
        screen line that was a multiple of the screen width.  This works fine
        for 40 and 80 column screens, but what do we do with the VIC-20, with
        its 22 column screen.  Solution:  make the _logical_ line length equal
        to 4 _physical_ lines, or 88 columns.
        When the Commdore 128 was introduced, the number rose to 160
        characters, which is 4 _physical_ lines in 40 column mode, or
        2 _physical_ lines in 80 column mode.  However, you can only take
        advantage of this in 128 mode.  64 mode is limited to 80 characters.
        
        To add to all this confusion, a valid BASIC program line (in memory)
        can actually be 255 (tokenized) characters long, but creating such
        a long line cannot be done from the built-in editor in direct mode.
        
        The AmigaBASIC, available on the Amiga, also does not have the 80
        column line limit.  However, that BASIC is SOOO much different that
        I am not surprised.  The older CBM BASICs, on the other hand, were
        all derivatives of the original Level 1 BASIC for the PET.

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$0CA)
	If a file is saved to a Commodore Disk Drive with the following
        characters: chr$(65);chr$(160);chr$(66), what will the directory
        entry look like?

	The filename will show up as "A"B, with the 'B' showing up to the
        right of the '"' mark.  This could be used to make program loading
        easier.  A file that showed up as "filename",8,1 could be loaded
        by simply hitting shift-run/stop on that line.

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$0CB)
	What is the maximum length (in characters) of a CBM datasette
        filename?

	References I have on hand say 128 characters.  However, the actual
        code on the 8032 and the C64 acts as though 187 characters can
        actually be sent (tape buffer-5 control bytes = 192-5=187).  The
        references that claim 128 characters are Nick Hampshire's
        _The VIC Revealed_ and _The PET Revealed_.  ANyone care to lay
        this one to rest? 

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$0CC)
	How many keys are on a stock Commodore 64 keyboard?

	66 keys.  This is the same number as found on the VIC-20 and the
        Commodore 16.

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$0CD)
	Commodore BASIC uses keyword "tokens" to save program space.  Token
        129 becomes "FOR".  What two tokens expand to include a left
        parenthesis as well as a BASIC keyword?

	TAB( (163) and SPC( (166).

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$0CE)
	There are 6 wires in the Commodore serial bus.  Name the 6 wires.

	1) Serial /SRQIN
        2) GND
        3) Serial ATN IN/OUT
        4) Serial CLK IN/OUT
        5) Serial DATA IN/OUT
        6) /RESET

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$0CF)
	On the Commodore datasette connector, how many logical connections are
        there?

	6. Opposing pins on the connector are hooked together electrically.


Jim Brain
j.brain@ieee.org
10710 Bruhn Avenue
Bennington, NE  68007
(402) 431-7754


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