Archive for June, 2012

After I’ve published the previous post, I was talking to TCD on #awesome BBS chat, and he suggested me use something else to position the cursor:

50000 PRINT LEFT$(“{home}{25 x down}”,y) SPC(x);

And to call the function, I could use:

X=10:Y=10:GOSUB 50000;PRINT “THE STUFF”

My first answer was: “Well, that’s cool but I think my POKEs are faster!“. He then made a good point about the high cost of the string functions I was using. Intrigued, I decide to run some tests comparing both ideas. The benchmark would simply assign 100 random positions to two arrays and print them using both methods. I’d be using the TI command to get the time at the beginning and the end of each function.

The random coordinates were used because my theory was that if the command above has to print, for example, 24 downs and 40 spaces it would take longer than print just few positions from where the cursor would be. On the other hand, the poke commands would go directly to the point!

To my surprise, on the first run, TCD’s method above was twice as fast as the POKE commands from my previous post. String functions fault!.. Right!? Actually wrong… Even passing the X and Y coordinates ready to be used in the function to avoid all string commands, the POKE method was still 50% slower.

That was an interesting discovery for me. Now I’m convinced!

 

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Last post, I told that I’d be showing new layout and stuff, but I have some ground to cover before I get to that point.

I thought that the first thing I should be doing is to create a routine that allows me to position the text using X and Y coordinates, (like the PRINT AT on the Spectrum, or Print @ on my beloved TRS family). Too bad the Commodore’s BASIC doesn’t have this kind of command, so after looking few different options in magazines and books, I’ve come up with this piece of code: (more…)

Star Text Project

Posted: June 15, 2012 in Commodore 64, Programming

After watching “The Search for Spock”, I remembered the text-based game Star Trek(c), first made in 1972 I believe (too bad Encyclopedia Britannica I have doesn’t mention it) by Mike Mayfield.

Although I know there are C64 versions of the game, I decided to work on my own version, tweaking the way I want.

First of all, I had to find some reliable old BASIC version. Looking on several BBS that I have access to, I’ve found a Super Star Trek(c) variant written in BASIC, which seemed to suit me well, because it doesn’t include any screen positioning command, displaying everything as scrolling up the text – very vanilla and easier to customize for the C64 screen size. (more…)

Isn’t it a good offer!?

Posted: June 15, 2012 in Commodore 64

I saw this advert in a Your Commodore magazine. Getting 50 games plus that amazing watch is an excellent deal!

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I’m very excited! Today, I received my Commodore 64C fully equipped with a 1702 monitor and a 1541 disk drive! I’ll be posting my findings and experiences about this amazing computer that everybody is talking about!

Yes, the monitor and the disk drive is still the older models, but who cares! They work perfectly and actually look nice besides my VIC-2o:

 

 

It is incredible! The 80’s are really an exciting time, with all those personal computers getting cheaper and cheaper, reaching millions of new users. This is what actually motivated me to write this Blog (Note to myself: register the name “Blog” – it seems it will stick!) and share what I’m learning. I’m no expert, so it will be interesting hear from you, and learn from your experiences as well.