shoestring

Black Tiger is a classic, love the FM sound track and spot effects. One of the best arcade platformers out there.

And that's only a fraction of what was in the arcades. http://mamepedia.com/game/category/platform?page=4

Are you sure ? They were very open about the platform from the beginning and provided software houses with "shitloads" of documentation and whatever they needed. The general public had access to the Programming reference manual which also had schematics in the backand and a description of what all the chips did.

The reason I got my first A8 in the first place, just to play Dropzone. I used to spend hours playing it on th c64 but the POKEYs more focused spot sfx make the whole experience more fun. There is something more satisfying about shooting and blasting enemies in the A8 version.

How do you two even get along with all the rivalry between the two camps ?

Looping it at work. That bass is badass.

For 3d style games even the Plus/4 outperforms the c64 in this area with its 1.76 mhz cpu clock. See Mercenary.

I was never a fan of platformers on home computers, they seem to lack the action I enjoyed in arcades and various consoles. Always something missing.. However, Sam's Journey seems to live up to the hype of it being a "console style platformer" so I'm looking forward to getting a copy of the game once my Ultimate-II+ arrives.

Correct, John Carmack came up with the algorithm known as "Adaptive tile refresh". The idea behind it was that you only redraw tiles that needed updating/redrawing instead of the whole screen.

The v2 preview looks most impressive, how is this even possible on a stock c64 ?.Thanks for sharing.

A lot of love went into it and it shows. I actually prefer the Atari version over the arcade.

He wanted to create a "family of computers" that had the same look. I don't know what he was thinking there.. should have just focused on the ST at that point. By 1985, the 8bit line were starting to becoming obsolete and then we saw new exciting tech, the Macintosh, Amiga, ST, then the Acorn RISC machines, consoles. Sure we did see some attempts to get more life out of the 8 bits with the C128 , Apple IIgs ..etc, but these weren't nearly as successful, Maniac Mansion used a scripting language called SCUMM ( Script Creation Utility for Maniac Mansion ). By the late 80s, games started to become so complex that it was extremely difficult to program them in 100% assembler. So the choppiness you see in some of the later games may be attributed to this.

Those 16bit commands are very handy, that's one thing I miss about coding on the z80. The 6809 is similar in that regard, for handling 16bit data arithmetic. The 16 bit index register was something that I really missed once I moved to the 6502, the ZP is a good compromise though, it just takes a little more work to set things up.

What advantages do you see the z80 having over the 8502 in the c128 ? They were both clocked at 2mhz which really hurt the z80s performance. The normal clock speed for a z80 is around 3mhz which is slightly better in performance compared to a 6502 when clocked at 1mhz. Commodore's engineers were really only concerned about CP/M compatibility on the z80 side of things.

Try reading the good one form the working machine and see if you get the same error. Chip is most likely bad or pin might not be making good contact with the device. If you've already tested it in the working machine and reproduced the same error, then there's your answer.

Similar to what individual computers did with the c64 reloaded. A new mechanical keyboard would be a huge plus

If you can even get one. Saw one on eBay recently sell for more than 450 euros.

I missed this. Check the +5v voltages at vcc on the sockets, then with the machine off measure the resistance between vcc and gnd on the same socket. If you had a dead short the machine wouldn't even power up. Since you replaced the socket, check your work on the solder side. You most likely just got another dodgy os rom or killed it, it's a mask rom so they can't take much punishment at all.

I would check U2 and U3 if you've already replaced the socket.

Sounds like a bad socket or support logic fault to me. Check the MMU and the 74ls138 as well.

Yeah understood, tested and working often really means “red light comes on”, especially if there are no pictures of the machine actually up and running. Every machine I’ve picked up was advertised as untested but I think about half were fully working and the others were a quick fix except for one.

Buy another working system that's fully socketed. Then you could substitute chips from the non working system into the working system until it breaks, much easier than subbing good chips into a bad system until it works because dead machines can often hide many faults.

The mindscape version was a bit of an improvement except for the sound.

Yes makes sense. Being fairly new to programming on the Atari, I wasn’t quite sure if there was a more accepted method of evaluating the memory when I looked at solving this problem initially. Good to see I was on the right track, even though I was wasting quite a number of bytes.

Here are two 240v versions that I've never seen before and were included in a 65XE sale. I ended up cutting off the chords and tossing both of them out.