Commodore Archives

30 years after its release it’s time to re-kindle with my first computer spirit – the C64. This was my first computer which changed my life forever. Thanks to VICE we can now enjoy the little guy again on modern hardware. Here are all my notes on how to talk to him, and his other friends from the 8 Bit Age.

Lottery Statistics in Commodore BASIC

In this episode I’m adding statistics support to my previous lottery generator on the Commodore 64. I’ll add an array that is updated if my supplied numbers have been matched, and how many times over how many draws this has happened. I’ll also add an option to pause the programme and display the statistics before … Read more

Matching Lottery Numbers on the Commodore 64

In this episode I’m amending my previous lottery number generator to take six lucky numbers from the user to match against the randomly drawn numbers from the Commodore 64. This will allow us to compare what the computer has drawn to the user’s input, as well as keep drawing numbers until the user input comes … Read more

Working with Keyboard Input in Commodore BASIC

In this episode I’ll show you three ways to take user input from the keyboard in Commodore BASIC. The INPUT and GET commands work on all systems, while the GETKEY command only works on the Plus/4 and C128. I’ll demonstrate how to use all of them. This will come in handy for our little lottery … Read more

Thoughts about the C64 Mini by Retro Games Ltd

In Europe, the brand new C64 Mini has just been released. Although I don’t have one myself, I’ve been following the Indiegogo campaign and have watched several “unboxing reviews” on YouTube. I must admit it’s a neat little machine, and I like the idea of somebody making the Commodore days available to a new generation … Read more

How to print numbers as columns in Commodore BASIC

In this episode I’m demonstrating how to print numbers in evenly spaced columns in Commodore BASIC.

On the C128 and the Plus/4 we can use a nifty little function called PRINT USING for this, with which we can format the output of any printed text or variable.

On the C64 and VIC-20 that function doesn’t exist, so we’ll have to convert a numeric value into a string (using the STR$ function), and then determine how long our string is. Following that we’ll have to manually pad our string value with as many spaces as are required.

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Sorting an Array on the Commodore 64

In this episode I’ll demonstrate how to sort a numeric array on the Commodore 64. The same principle works for string arrays, and of course on all other Commodore BASIC computers. The technique I’m using here is called Bubble Sort: in effect we’re comparing the first two items in the array, and if the left … Read more

How to generate Lottery Numbers on the Commodore 64

In this episode I’ll demonstrate how to draw random lottery numbers on a Commodore 64. The secret sauce here is not only the RND function to generate random numbers, but also two loops inside each other that prevent the same number from coming up more than once. Here’s the lottery generator code: 10 x=rnd(-ti) 20 … Read more

How to build a Word Splitter on the C64 in Commodore BASIC

In this episode I’m demonstrating how to build a word splitter on the Commodore 64. We’ll use string functions to parse a sentence and split each word off into an array of words so that they can be analysed later (for example, as part of an adventure game). Here’s the code I’m building: 20 input … Read more