Categories
C64

An Intro to 6502 Assembler

In the bad old days of the 80s and 90s computers weren’t as fast as they are now. You had to fill ’em up with leaded fuel and they were noisy and hot and you had to keep the windows open to let the fumes out.

Well, maybe not. They weren’t as fast as the handheld machines in our pockets now but I’ll bet that a larger percentage of users back then at least tried to code something. People had to because it wasn’t always easy to get games. You had to go down the shops and get out of the house to buy any new software! You had to open the manual to find out how to load anything!

So it was that I figured out that I’d rather be coding than playing games, and with the purchase of a book on assembly (that has sadly gone missing in the last year) I got busy and created a bunch of demos on the C64.

I wish I’d had this video to watch when I was starting out! If you’ve done any sort of assembly programming it won’t be anything new but it’s presented in an easy to understand manner and is worth watching if you’re at all curious about how computers work because a lot of the terminology is going to apply to other systems too.

I’m really looking forward to seeing the rest of this series. I want to get back to doing some assembly programming. There’s plenty of documentation out there but it’s a matter of finding the time and energy to do it.

Categories
Podcasts

If you love “13 Minutes to the Moon”

13 Minutes to the Moon is a BBC podcast telling the story of the first Moon landing and all that led up to it and it’s gripping listening featuring recordings from the time, great music and great story telling.

However, if you want to dig deeper into the Apollo missions I would recommend the Omega Tau podcast episodes about the Apollo missions. I already blogged about them but it’s worth repeating since there’s probably a whole new audience that will want to hear more!

Episode 83 is an interview with W. David Woods about his book How Apollo Flew to the Moon:

… where he describes in great length all the detail a geek wants to know about how the Apollo spacecraft and the flights to the Moon worked. In the episode, we basically go through an Apollo mission and discuss aspects such as the mission structure, the workshare between the crew and mission control, communication and telemetry, guidance and navigation, approach, landing and re-launch on the Moon as well as re-entry and landing on earth.

In episode 97 he returned to talk about exploring the Moon!

This is the long-awaited follow-up to the first Apollo episode, once again with W. David Woods, author of How Apollo Flew to the Moon. In this episode we cover that part that we omitted in the first episode: the time on the moon. We talk about life support, the various scientific instruments and experiments as well as the technology and use of the lunar rover (about which David is actually writing another book).

If you’re really interested in the Apollo Guidance Computer you’ll love episode 167.

This episode is a mix between computer architecture, programming and (historic) space flight. We cover the ins and outs of the Apollo Guidance Computer. Our guest is Frank O’Brien, who wrote an incredibly detailed book about this machine. In the episode we cover the hardware architecture, the instruction set, the various layers (native, executive and interpreter) as well as some mission programs.

Follow those interviews up with episode 218, A Life in Apollo where Markus interviews George Knudsen about the Saturn 5 launch vehicle and Apollo.

George Knudsen started working in 1958 on the Redstone missile, and moved on to working on the Atlas ICBM. Later he worked on the Saturn 5 launch vehicle, where he was responsible for the fuel tanks. He was on the launch team at Cape Canaveral for various Apollo missions. In this episode with talk with George about his work in this fascinating period of science and engineering history.

The Omega Tau podcast has been going for many years and they have episodes on all sorts of engineering and scientific topics. For other episodes related to Apollo have a look at this search on his blog listing many more episodes.

Categories
C64

Tunnel Vision by OMG

Tunnel Vision, C64 demo

So, apparently this is the first demo by this developer and it’s amazing. Hell of a fire effect.

I discovered this while testing the SD2IEC on my C64. Assembly64 has a “One File Top 200” directory that I was working on because the disk images have characters the filebrowser has trouble with. This small bit of bash shell script will sanitise it before viewing on a C64:

for i in *
do
  mv -v "$i" "echo $i|cut -c13-|tr '[:upper:]' '[:lower:]'|tr -cd ' a-z0-9'"
done

It changes the filenames to lowercase and then removes anything but a-z, 0-9 and space and also cuts out the first 13 characters . There are still a few shortened filenames but it looks much better now.

Edit on July 8th, 2019: The SD2IEC is slow when there are lots of files in a directory, plus the directory contained other directories so I decided to move everything into directories named after the first letter of each directory with this code:

for i in *
do
    new_dir=echo "$i"|cut -b 1
    mkdir -p ../1/$new_dir
    cp -v "$i"/* ../1/$new_dir/
done

Everything’s in sub directories of a new directory called “1”. There are multiple demos in each directory but not enough that it’s too slow. 🙂

Categories
C64

Sam’s Journey with two fire buttons

I figured out how to play Sam’s Journey on the Commodore 64 using two fire buttons! One as a normal fire button and another for jumping.

C64 joysticks only have one fire button so jumping up in platform games requires you press up on the joystick. Back in the day we knew no better and did our best using the directional movements. It’s not very precise as it’s easy to slip into left and right too. Pressing a second button to jump was a luxury NES owners had! C64GS owners had a joystick with 2 separate fire buttons but I think there was only ever one game that took advantage of that feature.

Unfortunately you’ll have to use the Vice C64 emulator, Virtual C64, or another C64 emulator that allows you to map keys to joystick actions.

First of all, open the joystick settings in Vice. Here’s the one from version 3.1.

Assign a keyset to joystick 2. I used the keys T, G, “,” and “.” and the right CTRL to fire. Sam’s Journey actually plays reasonably well using those keys if you don’t want to go any further.

However, if you want to use a controller you’ll need another program to map those keys to controller actions. On MacOS I found Enjoyable, a free application that allows you to map controller buttons and other inputs to keyboard keys or mouse movements.

I simply assigned left, right and down on the d-pad to the correct keys, and then two fire buttons to CTRL (fire) and T (up) respectively and it worked!

The game is definitely more enjoyable but it’s just as hard as before. I could have sworn I ran out of lives in the past to be thrown back to the start of the level. Now I kept getting put back at the last checkpoint, which is an improvement I have to admit as I died quite often. 🙂

Categories
C64

We Come in Peace Demo

This is just amazing. All done on a lowly C64 by Censor Design and Fairlight. Grab the demo from csdb. Unfortunately it doesn’t work in the SD2IEC because it has a fastloader. I should buy an Ultimate II+ or Ultimate 64 shouldn’t I?

Categories
C64

C64 Spotted in Cash Connectors

In Cash Connectors, North Main Street Cork. €119.99 for a C64, datasette and I think 4 games. No mention of whether it’s working or not or even if it comes with a power supply.

First time I’ve seen a C64 in a shop here in years. Last time might have been in Maddens on Princes Street some time in the early nineties.

Categories
C64

New C64 Adventures

It’s no secret that I’ve been a fan of the Commodore 64 for many years. It was my family’s third computer, after a Vic20 and 48K ZX Spectrum. I don’t count the Telesport, I couldn’t program that! The C64 was my main computer from 1989 to about 1994 and I went from programming in BASIC to exploring the depths of the machine with an Action Replay cartridge and programming demos in assembly. Since the late nineties I contented myself by using different emulators like PC64, Frodo and Vice but in the last year or so I’ve wondered about owning one again.

What I would consider the first resurgence of the C64 world for me was finding the Commodore Format blog. There’s also Zzap64.co.uk which has been going for ages but it’s an invaluable archive site. The CF blog has regular blog posts about this old magazine and features about new developments and I love it. I could blame the community of C64 fans on Twitter, the C64 sub Reddit and various C64 groups on Facebook. They’re always going on about playing this game or that game on “real hardware”, or how a certain demo doesn’t look perfect in an emulator. But really, I’d say it was the fanzine FREEZE64 that finally piqued my interest again. It’s a great read and Vinny, who publishes it, is always posting photos of the things he’s doing on the machine. The fanzine brings me back 30 years to when I first got the machine.

Peer pressure finally won. I bought a C64 on eBay and it arrived yesterday!

I’ve always wondered if it was possible to use a modern controller with the C64 and there are a few adaptors to do that. One of those is the TOM Rev2 adaptor and extension cable. It’s due to arrive at the end of the month, so fingers crossed it works well.

I have a 1541 II disk drive in the attic but there are better storage solutions available for the C64 now. One of those is the SD2IEC, an SD card reader for the machine. I bought the thefuturewas8bit SD2IEC and Fastload Cartridge. Conveniently an 8GB SD card can be purchased which is enough room to fit practically every C64 game on it!

The C64 produces a composite video signal and a video signal that was s-video before that was even a standard. My monitor doesn’t have either RCA/phono sockets, SCART or s-video port but it does have HDMI so I needed a converter. Scouring websites and forums for information about the best way to connect a C64 to HDMI is exhausting. Recommendations to buy one converter are followed by discouraging remarks from others about the same device. In the end I checked Amazon reviews and this Ex-Pro video converter seemed to fit the bill. It has phono and s-video sockets too!

Finally, I needed a video cable. I messed up and bought a C64 DIN to phono/RCA cable instead of s-video, but it works well enough. The screen image is nowhere near as clear as an emulator like Vice but I’ve ordered a similar cable with an s-video plug that I hope will be better.

The first thing I tried was one of my demos, Bits ‘n’ Bobs and it was amazing to see it run! The picture isn’t perfect and especially on this wide monitor everything is stretched. 4:3 it is not!

In a later demo, the CFORCE demo, I displayed a FLI picture in one part. That picture annoyingly bounced up and down which is probably a result of displaying on a modern monitor. On an old CRT it was fairly solid, apart from the usual fuzziness when displaying FLI pictures.

Getting it all set up was a challenge, mainly to find space for it, but I made room. Using the “picture in picture” mode of my monitor the display is smaller and the effects of the component cable less noticeable.

The SD2IEC and fastloader cartridge are a game changer. No more fiddling with ageing physical disks that are likely to be unreadable. I’m already missing the Action Replay though. F1 to load and F3 to list a disk is just that tiny bit more convenient than the Epyx Fastloader equivalents.

I just bought an Over Voltage Protector as I’m paranoid. This machine came with a Micro Mate power supply but power supplies fail and the C64’s chips are sensitive to more than 5.5V. This should hopefully stop that happening if the PSU fails.

Now I’ve got one of these machines I want to get an Ultimate 64. It’s a fascinating bit of kit, and the price of it put me off before, but it’s actually cheap when you consider everything it does!

So, what games should I play on it? I’m without a joystick or controller so it’s keyboard only. I asked on Twitter and I have to try Thrust, The Sentinel, West Bank, Skooldaze and the recently released Neutron on it as they all support keyboard. I already played Stunt Car Racer which brought back plenty of memories. 🙂

Edit: The s-video cable arrived and the video quality is much better. There’s still faint vertical lines but I can live with those.

Edit on 12th June: I just received this female RCA to 3.5mm earphone jack and I can finally hear the SID on decent speakers! The sound from my HDMI monitor is woeful so I’ve been looking forward to this for a while.

Categories
C64

Rivalry (C64) – GP Bonzai Censor FLT Bonzai Offence

If this is what rivalry can produce let’s have some more fighting and arguing! What an amazing C64 demo!

You can find the demo here on csdb, and there’s also a live video made at Revision 2019 where the demo was released.

Categories
Games

A SNES Mini found a new home

The first Nintendo console I owned was the Gameboy Advance. The earlier Nintendo machines passed me by as I was busy coding on the C64, messing with the Amiga and PCs and college then kept me busy!

I never owned a SNES and Nintendo 64 and rarely even used the real hardware. The only game in the SNES Mini collection that I’m nostalgic about is F-Zero as I loved playing that on the Gameboy and it plays perfectly on this diminutive machine.

This is a lovely piece of kit though. I like the menu system and the two controllers are wonderful. Now I know why people go on about these and seek out their modern equivalents in 8bitdo equipment.

Apart from games I’m looking forward to tinkering with the machine, and maybe adding a C64 core although the lack of a proper keyboard can cause problems..

Categories
C64

The Great Giana Sisters on Ebay

I was going to make a joke about how a clone of The Great Giana Sisters had been released on the C64 a few weeks ago, but I would hazard a guess that only a handful of my readers will have the faintest idea what I’m talking about. Instead, you’ll probably remember that most gaming sites were abuzz with the news that Super Mario Bros had been released for the C64. That excitement then turned to fear and anger as Nintendo issued a takedown notice to one blogger who had a download link on their site. They have to protect their IP but the game is still available in several places including the Internet Archive and should be easy enough to find in the future.

If you’re at all interested in Super Mario Bros then grab your copy as quick as you can, just in case a massive database of copyright works is unleashed on the Internet blocking everything no matter how old it is.

The conversion of the game to the C64 is more than just a direct port. Both machines use the same (or similar?) CPU, a modified 6502 in the case of the NES and 6510 in the C64. The developer ZeroPaige spent 7 years modifying the raw assembler from the NES so it would work on the C64. He had to modify the graphics system to use C64 sprites and the sound system had to be reworked to use the SID chip of the C64.
The port also takes advantage of any extra hardware you might have plugged into the C64, or even uses the extra power of a Commodore 128 if you’re using that. Here are two videos showing the game off on a C128 and also on a Turbo Chameleon V2, an FPGA based C64 machine. The game suffers slowdowns on an original C64 so it’s best played when the machine has some help, or in an emulator. I have a C64 DTV. I wonder how hard it would be to get it running on that?

Super Mario Bros on a Turbo Chameleon V2
Super Mario Bros on a Commodore 128D with SuperCPU

It seems Nintendo aren’t really interested in the C64. Many years ago Gary Lidon and Gary Penn created an SMB demo for Firebird who sent a video of it to Nintendo. They responded with a cease and desist order!

Rainbow Arts apparently did the same and were rebuffed but they reused their code and cheekily created The Great Giana Sisters. Nintendo promptly came after them at the time and the game was taken off the shelves within weeks. Pirated copies are simple to find but the original must be very rare. A version of the game with the main character changed to Mario did find it’s way online but it’s basically Giana Sisters. No bad thing since The Great Giana Sisters is a great game. It’s one of my favourite C64 games.

After that detour down Nintendo lane, let’s get back to reality. If you want your very own physical copy of The Great Giana Sisters then check out this Ebay auction. Priced at an eye watering £199.99+postage I don’t think it’ll be an impulse buy but some collector is sure to snap it up.

As a historical note, there are two conversions (Atari and Ocean) of the original Mario Bros for the C64 if you really want to play it. I haven’t played either of them. I didn’t even know they existed until a couple of years ago!