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28

There are two elements: The background The sprites The background is very straightforward: The vanishing point never changes so you have one graphic with a checkerboard in perspective. That graphic takes 2 bits per pixel so that you have the 2 checkerboard colors and the edges of the field color. It just needs to be the width of the screen + 4 tiles (2 ...


26

The physical design of the Atari 800 was radical, but not for reasons related to the aspects you highlight. As others have commented, using multiple boards for a system was pretty standard at the time. S-100 systems for example were based on a backplane, with system features implemented on multiple boards connected to that. (The Atari 400 and 800 were ...


25

The gameplay can be implemented without any 3D calculations (or very little, depending on your definition of 3D calculations): The checkerboard never rotates, so it can be drawn using affine segments and fills (y = ax + b); the players never get close enough to the edges (on the goal sides) for the vanishing point to be an issue. The checkerboard isn't ...


19

Most classic computers will work fine on a TV with proper composite inputs. You want to make sure your TV has aspect ratio selection as many simply horizontally stretch the 4:3 image to 16:9. As for Atari's, it will depend on which model you have and what cabling you have. I've very successfully run Atari 800XL and 1200XL systems with LCD TVs using the ...


18

De Re Atari describes the cassette boot protocol, which helps understand why bootloaders were (nearly) always used. In cassette boot mode, the operating system reads a record from the tape recorder and loads the following information: byte 2 gives the number of records to load (up to 256 records, each containing 128 bytes, so 32 KB in theory) bytes 3 and 4 ...


15

Looking for either "rose.neo" atari or "rose.pc1" atari in Google images with an exact requested size of 320x200 yields this result, which seems to match your description pretty well. Could it be that one? EDIT #1 Here is a better version from Demozoo. EDIT #2 The original Neochrome file can be downloaded from this page.


14

I can only really answer from my own perspective, and I only wrote real code (other than simple BASIC programs) on an Atari over the last couple of years. IDE Used In terms of classic tools IDEs were relatively light compared to tools you get today. I worked using Devpac 3, which is a good assembler that includes some useful features and a debugger. STOS ...


14

In the end, I decided that it had to be easier to take the keyboard apart than to de-solder the 4051's and so I carefully removed the 18 tiny screws from the back of the keyboard. It wasn't nearly as bad as I expected (I was concerned that I was going to have springs everywhere). After disassembly I fired up the Atari to try and see if I could get the A ...


14

Ignoring the copyright issues of such an endeavor, you're going to have a very hard time of ripping audio in a conventional sense. Old games don't store their sound effects and music as waveforms like modern PC and console games do. This is because both the audio hardware on old computers and consoles was much more limited, and because there wasn't enough ...


14

At that point in time, Atari had separate divisions for the Home Computer market and the Consumer Electronics, or console, market. There was a lot of competition between the divisions. The Consumer Electronics division was the pride of the company due to all the cash that was rolling in thanks to the Atari VCS(2600), and it seems there was a bit of hubris ...


13

I used to program on the Atari about 20+ years ago, so I might be a bit rusty on the subject. Also I used to mainly write demo effects and music, so I wasn't working on core game development directly (other than writing music for some). IDE is a more modern concept, so you probably won't find one on the platform itself, but there are some out there for ...


13

If you're willing to spend some money, there are some nice options using the Atari's SIO port (the big trapezoidal plug on the side). Maybe the most flexible option is the SIO2PC adaptor, which lets you connect your Atari to a PC via serial or USB connection. This lets you do things like access a directory on your Mac or PC directly from the Atari, and ...


13

MOS was renamed to Commodore Semiconductor Group (CSG) sometime after Commodore bought them in 1976. After Commodore folded in 1994, the CSG division was bought by its former management and renamed to GMT Microelectronics (Great Mixed-signal Technologies). They continued with design, manufacture, and marketing of analog and mixed-signal power management ...


12

The POKEY module has a random number generator, six scan lines, eight potentiometer ports, three timers, a serial port and four audio channels.[2#1] Hardware The POKEY chip (C012294 (original), C012294-02 (dual-core) and C012294-04 (quad-core))[1§2] have 40 lines. These are: Pin 1: Vss: Ground[1§3] at 0V. Pins 2 - 6: D3, D4, D5, D6, D7: Data Bus I/O.[1§3] ...


12

I don’t think they ever recommended a monitor. As far as I can remember, Atari communications showed Atari computers on their own, or connected to TVs; see for example this 1200XL advert, and Atari UK’s magazine, Atari I/O (issues 2, 3, 4, and 5). At least in Europe, 8-bit Ataris produced nice video on most TVs (I didn’t grow up with NTSC so I don’t know how ...


11

Memory beyond 48 KB on 8-bit Ataris is all based on bank-switching, since the 6502 processor only has 16 address lines. The CPU can address 64 KB total, and that has to include ROM and memory-mapped I/O (0xD000-0xD7FF) as well as RAM. On XL/XE Ataris, PIA Port B, at address 0xD301, is used to swap parts of physical memory in and out of various banks, so ...


11

If bit 0 of location 842 is set then the keyboard scanning routine immediately returns 0x9B which is the code indicating the ENTER key has been pressed. In short, a surprisingly literal effect. The keyboard scan is part of the "OS" ROM built into the machine. There's a source listing I'll excerpt from: Atari 800 ROM OS Source Listing ICAX1Z is a zero ...


11

The order of switching should be relatively arbitrary - After all, there were Ataris around (like the Falcon or ST/E) that didn't have a separate power switch for the hard disk and where it was relatively random what stopped first. But, if in doubt, ask the manual. The Atari Megafile manual says the following: (I'm especially fond of the "...when the ...


11

The biographical evidence for both Jobs and Wozniak indicates that Wozniak's version of Breakout (which is NOT the version Atari would release publicly) was likely developed in the first half of 1974. From the biography of Steve Jobs, we know that in early 1974 Jobs was working at Atari, having been hired in 1973 at the age of 18. We also know that he left ...


10

For posterity, here is the solution that allows you to convert the video output of an Atari Centipede arcade game to VGA output. Aquire the GBS-8200 You need to add an additional wire to the video wiring loom for composite sync. This composite sync signal is already generated on the Atari centipede motherboard and is brought to the video connector, but ...


10

To identify SIMM sizes based on chip IDs, search the Internet for the chip IDs to see what each chip is (chip datasheets are a good way to find this out), then multiply the chip capacity by the number of chips. For example, an M514100D (D probably is a newer version but otherwise compatible with M514100B) is a 4Mbit x 1 fast page mode DRAM chip. So if you ...


10

There is a tool called STZip which is a ZIP archive/unarchive utility for the Atari ST computer. Why not zip up the STOS game creator into 300kb chunks on multiple floppies, and join the files on the ST itself? There is another tool called DC Xtract Plus that may work as well. Both of these applications should fit onto a single floppy. There is also a ...


10

No. At least not in a software compatible manner. The PIA which is used in the 800 to read joystick ports 3 and 4 was repurposed in the XL systems to control memory mapping (eg. disable OS ROM, disable BASIC ROM, etc.) and for other special XL functions. Source: http://www.atarimagazines.com/compute/issue57/feedback_atari_amnesia.html


9

Super hot chips are usually dead chips. That said, with the Atari one common culprit is a bad power supply — certain models are known to go bad in a way that results in excessive voltage at the socket, which can easily fry multiple ICs on the motherboard. So first step would be to verify the power supply is good (preferably by not connecting it to another ...


8

One solution is to use the program published at COMPUTE! ISSUE 76 / SEPTEMBER 1986 / PAGE 100 : http://www.atarimagazines.com/compute/issue76/AtariML.php The program heavily utilizes the CASIC "self-programming trick". First, let's explain the trick. An example - dynamically allocating a string of variable length - is located starting with line 31570: PH ...


8

The major difference between drive speeds in classic computers is the philosophy and design of the drive and it's attachment mechanism. Some computers, such as the TRS-80/CoCo and Apple II lines, used a bus-level connection that allows the drive's controller to dump data in a parallel fashion from the drive to the computer's RAM. Other lines, such as Atari ...


8

I've found that the old Atari keyboards can lose conductivity and that pressing they key repeatedly, not necessarily with a lot of pressure, can revive them. I've had Apple II keys start working again after pressing them a hundred or two times. Assuming the above isn't the issue, if the rest of the keys, particularly in the same row and column work (not ...


8

As others have said, Atari didn't recommend a monitor as far as I'm aware, but I can confirm S-Video on a Sony PVM looks fantastic. I remember as a kid my Dad telling me why he'd bought a Sony TV (a little 14" Trinitron) and him showing me the manual for Archon. Interestingly enough, EA did recommend a Sony ;)


7

Actually, you're asking about two separate things here. The first is "how to get my tapes to a PC" and second is "how to convert tape records into a disk file/image". The former can be solved with http://turgen.sourceforge.net, the latter is a bit more complicated. There had been many native tools for this task but the conversion is not always possible -- ...


7

The loading code does it; you can see that the CPU writes to one of the audio registers during the load if you disassemble the ROM. The "feature" could be disabled through code although it was usually reassuring during tape load. As far as tapes go, the program was stored on one track and the second track was free for audio; I have only seen this feature ...


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