DanBoris

I wasn't knocking the need to accurately preserve the content of the magazine, just making the point that's it also still has useful information in it. I actually have a fairly extensive collection of Byte and Creative Computing magazines and would like to see them accurately preserved with high quality scans. Same could be said for 95% of the magazine that are currently sold today.

I have to disagree with the "raw information" not being necessary. I recently acquired a IMSAI 8080 system with a floppy drive that I could find no information about on the Internet. It also had a floppy disk controller that again isn't document anywhere I could find on the net and used an IC chip that I could find no information on either. Digging though some old Byte issues I ran across an article about how to interface this exact floppy driver to a system using the same unidentified chip that is on the controller I have. This information will be invaluable in getting this system running again.

Yep, this is all it does. Once the verification is complete the bios is swapped out for the cartridge ROM so isn't even used after the game starts. So technically it's more of a boot loader then an actual bios.

The difference between Combat and 32 in 1 is not surprising since Combat was an early cartridge and the 32 in 1 was much later. Chips generally get more power efficient over time. Besides the PSU the other thing you need to look at is how much current the voltage regulator in the system can handle.

Just rescued this from a trip to the dump! Hopefully with some work I will be able to bring this and the associated hardware back to life! More pictures here of the hardware I got with it: https://picasaweb.google.com/117618066474050188669/IMSAI#

The clock is the key to knowing when to read the data. The address and R/W are valid on the rising edge of the clock and data is valid on the falling edge. As for your third question, no the program counter is not accessible, it's internal to the processor.

Never noticed the variations in the CS pins on the different sites, glad mine was correct!

Just ordered mine, can't wait to read this!

Very cool! This bring back memories. I actually got one of these for Christmas back in the 80's. The simulation is very accurate right down to the not so responsive controls.

I remember those days. I also remember there were people who got very upset when MAME added support for games that where in these standalone emulators. They were sort of accusing MAME of putting these single game emulators "out of business" as it were.

As I mentioned above the second release of VVCS was 6/18/1996, an I don't have a record of it but I am pretty sure the first release was just a couple weeks before that.

Action Pack was the first that I am aware of, it was released in June of 1995. I remember back then a lot of people were skeptical at first that it even was an emulator. Next was probably x2600 which is what my Virtual VCS emulator was based on, but I have not been able to find any record of when that project was created, but it was prior to June of 1996. My Virtual VCS emulator had it's second release on 6/18/1996. I don't have any documentation of when the first release was but I think it was only a couple weeks earlier. The first playable release of Stella 7/12/1996. Best I can find PCAE came in late 1996.

I've never seen them either. Mitch is right, if anyone has them it would be Curt.

I remember this when I was writing my 5200 emulator, since I didn't emulate this behavior initially Star Trek wouldn't work. I believe it's the only 5200 game that looks for multiple key-code values..

Wow, this looks great already! Wish you had been programming 7800 games back in the day, the system might have been more successful!

Good purchase! I used that same EPROM emulator for many years until I somehow managed to blow out the micro-controller on it. It served me very well.

A .A78 file is a binary cart image with a special 128 byte header added to it that described the cartridge format. Below is the original specification for the header, although I believe some people have extended it since this version. You can setup some data decelerations at the start of your source file to create the header, or use a tool like 78hdr to add it afterwards. As for the 'encryption', it is necessary for the game to run on an emulator. It's not really encryption, but instead a digital signature attached to the cartridge data which is validated by a routing in the 7800's bios at startup. Without the encryption key the Atari logo will just keep cycling at startup. To work with this emulator ROM images must have this 128 byte cart header at the start of the raw data. This header allows the emulator to know the features of the cart thus preventing you from having to use a bunch of command line options. 0 Header version - 1 byte 1..16 "ATARI7800 " - 16 bytes 17..48 Cart title - 32 bytes 49..52 data length - 4 bytes 53..54 cart type - 2 bytes bit 0 - Pokey cart bit 1 - Supercart bank switched bit 2 - Supercart RAM 55 controller 1 type - 1 byte 56 controller 2 type - 1 byte 0 = None 1 = Joystick 2 = Light Gun 100..127 "ACTUAL CART DATA STARTS HERE" - 28 bytes

Wow, can't believe people still remember Virtual VCS. I the case of VVCS, it didn't die because it was inaccurate, it died because other emulators like Stella quickly surpassed what I had done so I saw no point in continuing and moved onto other things. Dan

I found this entry for Flim Flam on KLOV: http://www.arcade-museum.com/game_detail.php?game_id=7826 The cabinet doesn't look the same, and the one I posted the pictures for appears to be color (unless that's an overlay) and Flim-Flam is black and white.

I am trying to figure out what this is. These picture came from a friend of my sister and she describes it as "Pong". I doesn't currently work so they only get that test pattern screen, but this at least show's it's a color game so probably early 80's. In the picture of the screen you can see the company name "Rover Leisure Products Co" in Siloam Springs Ark, but Googling that name turns up nothing. Anyone have any ideas?

Great work! Glad someone was able to pick up where I left off.

I still have the invoice from my first computer system: 800 16K Computer $679.00 810 Disc Drive $449.00 850 Interface $169.00 410 Recorder $76.00 Joystick $20.00 Video Easel $35.00 Star Raiders $60.00 Epson MX80FT Printer $559.00 Printer Cable $30.00 32K Expansion Board $159.00 Touch Typing $20.00 Atari Word Processor $159.00 Breakout with Paddles $43.00 Graphit $17.00 Statistics $20.00 Visicalc $169.00 Atari 800 dust cover $7.99 1 box floppy disks $36.00

Wow, I can't believe people are still using Virtual Super System! It's really out of date and there are better emulators out there now. I would try Atari800WinPlus or Jum52. Dan

There are programs out there that will securly delete files, but the problem is finding all the files that need to be deleted. There are a lot of different places that a file with personal information could end up. Just deleting My Documents wouldn't necessarily be sufficient. Dan

Exactly, it's called sprite multiplexing. Works particularly good for Bounty Bob since the enemies only move horizontally and are always at a predictable vertical location on the screen, so it makes it easy to re-use the players as you go down the screen.