Issue 20: Jun 2002
Features
- | Foreword
- | Tip of the day
- | Busy Bee
- | Atari in the USA 2002
- | Jump out of the Window or learn Polish
- | Seasoning with MSG
- | Video games in Europe - the early years
- | Atari Emulation - Part 3
- | Vision - An Introduction to Albums
| Setting up Atari800Win PLus Welcome to the third part in my emulation series, this month I will be spending some time taking you through the basic steps to setting up an emulator. I will also be discussing a few ways of getting ROMs from your real Atari into your emulator without having to scour the internet for illegal ones. Setting up and using an emulator can be a little confusing if you have never used one before. Many authors assume that the end user has a great amount of knowledge about the computer they are wishing to emulate. For example, you may have only ever used an Atari to play games on, to type letters or do the accounts and were never interested in how it worked. If this is the case, you will find statements like "set BIT 7 on PORTB to access memory location... blah... blah..." just a little confusing! Thankfully most recent emulators use an intuitive interface to access most of the relevant parts of the virtual machine, but in order to use them properly you must first have a basic understanding of how the original machine worked. The following examples will take you through every step of setting up the emulator Atari800Win PLus. I have chosen Atari800Win PLus mainly because of its Windows based interface, but also because it is one of the most comprehensive emulators I use. Installation The installation is in the form of a short wizard. I am not generally fond of wizards, but this one is both short and functional with three basic steps; Shortcuts Operating system and BASIC ROM images File association of Atari files Step 1 - Shortcuts Here I would suggest leaving both boxes (Start Menu and Desktop) checked so a shortcut for the emulator is created on your desktop and within your Start Menu. Click the Next button to continue. Step 2 - Operating system and BASIC ROM images This step can be awkward if you are not sure where your ROM files are. If you have several emulators like myself, I tend to have a folder just for ROMs and set all my links to the one folder. For simplicity you can copy your ROM files into the ROMs folder created when you originally unzipped AtariWin PLus. So that AtariWin PLus knows where to find your ROM files, you need to type in the location of the files here or locate them using the Windows file selector by clicking on the buttons for each OS. Click the Next button to continue. Step 3 - File association of Atari files For now, I would suggest leaving the boxes unchecked because some of the file types may clash with your current Windows system settings, however, feel free to change it later when you are more confident with the software. Click the Finish button and your virtual Atari should burst into life. To get any further you will need some disk images, preferably DOS 2.5, DOS XE, or MyDOS. Although they can be found bundled with other emulation software, the only one that has obtained permission from Atari to do this is the author of Xformer 2000. If you like, play around with BASIC, you will find that the emulator behaves exactly like an Atari (although using the keyboard takes a bit of getting used to). Should you experience any problems, the help menu is very comprehensive and will take you through the basics of using the drop down menus. Like I said we need some disk images, this is where it gets interesting. For public domain software, I recommend that you visit www.newbreedsoftware.com/xlsearch/. This site has literally thousands of on-line disks to both download and run, however, it is more fun to port across your own. Transferring disk images and your operating system To physically transfer files from a real 8-bit to a PC has been the holy grail for years. Many ideas have come and gone but the few that remain are both tried and tested and relatively easy to do. These are; Direct connection to the Atari. Via a modem or null-modem cable. Using a 5¼ inch disk drive. Using the original Atari disk in a modern PC is impossible as the Atari disk format is totally incompatible. However, we can use a modified drive such as the Disk Doubler or Happy 1050 to write the information in the standard IBM format for 5¼ inch disks. To do this you will need such a drive in your PC, but unfortunately they disappeared from PCs a decade ago and are now quite hard to obtain. Although do not give up too easily as I was lucky to find two brand new 5¼ inch drives at a boot fair. An alternative method is to transfer the files using a null-modem cable using terminal software on both the 8-bit and PC. However, how many of us have an Atari 850 interface or 8-bit modem?! We therefore need a modern solution which everyone can use. This leaves us with a final solution... to directly connect the 8-bit to the PC. Direct connection sounds like madness, but it's not. The Serial Input/Output (SIO) interface on the 8-bit is quite similar to the RS232/Serial connections on a modern PC. Using a suitable cable and software it is possible to fool the 8-bit into thinking it is talking to an Atari piece of hardware, when it is in fact talking to a modern PC. One such cable is the APE interface available from Steven Tucker. It costs around £80 for the cable and software, but is well worth it. I was going to construct the cable myself but Steve provides one in a special moulded cable with over 500MB of software on a CD-ROM which includes a personalised copy of the APE software for Windows 98. I won't go into detail about how to set-up and use APE here as I am saving that for another article. However, I am pleased to report that APE's instructions so easy to follow that I was up and running in five minutes flat. The following photograph shows my Atari 65XE with the APE cable in the SIO port on the right of the Atari and the video cable plugged into the front of my video recorder.
I use the built-in capture facility of my Asus video card in my PC instead of a television, this keeps screens to a minimum on my PC desk and allows screen grabs for articles such as this.
APE has many functions. One of the best is to use a folder on your PC as a virtual disk. The virtual disk concept works by taking the raw data from the diskette and creating a single file version of it on the PC's hard drive. For example, let's say that the following data represents information stored on an Atari diskette: 0 0 0 123 54 67 98 0 0 0 0 0 3 8 34 241 33 6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0. The numbers represent data while the zeros represent a part of the disk which is unused. What a virtual disk does is take the data numbers and create what is effectively a large text file containing ASCII data. If you look at a virtual disk in Notepad on a PC it looks just like gibberish. This is because the information is not in a form of English, but the raw data which the Atari understands. Virtual disks should represent the size and format they were originally in (single, enhanced or double density). APE gives you the option of using your hard drive as an Atari diskette, that is, you are writing files directly to the PC, it is not hidden in a virtual disk. This subsequently allows you to use as much hard drive space as you like... 30GB enough for you? There is no real limit, only what the Atari can access at once which depends on the DOS (Disk Operating System) you are using at the time. Those of you that are familiar with Atari DOS 2.5 should keep folders small as this DOS cannot access large amounts of data at a time. Also remember that Atari's DOS generally cannot understand sub-directories / sub-folders. It is therefore recommended that you treat each folder as a separate disk. By writing directly to your PC in exactly the same way your PC access files it means that we are able to copy files and create our own ROM files. The following screen-shot shows the APE software with all eight Atari drives represented. Disk drive one is a virtual disk with DOS 2.5 while drive two is what APE calls a PC-MIRROR (a drive represented by a folder on the PC). If you have used Atari DOS before, you will not doubt be familiar with the copy disk option in the menu. With the APE cable daisy-chained to say a Atari 1050 disk drive, copying your physical Atari DOS diskettes to a virtual disk on your PC couldn't be easier. There are no catches... it is really as easy as that! APE turns your PC into a piece of Atari hardware the old 8-bit thinks it is really talking to a second 1050 disk drive. Let's first try copying a DOS disk to a folder. Open the folder on your PC and it should look something like the following; You will notice however that DOS 2.5 will not let you copy DOS.SYS or DUP.SYS across. This is because it checks to see what format the disk is formatted in first which confuses the DOS and it will not do it. The same happens if we try to write just the DOS files to disk drive two. Solution? We must use either the APE software, or Atari800Win PLus to create a virtual floppy disk and use that instead. Here is how to create a new virtual disk using Atari800Win PLus; From the menu bar at the top of the screen choose Atari, then select Disk drives. In the Drive Selections dialog, select the New image button at the bottom left of the window. In this dialog, choose a disk density, preferably enhanced if you wish to use Atari DOS 2.5. The option at the bottom of the window is asking which drive you want to put it in, but don't worry too much about it as it only affects the emulation software, we just need the disk image. Click Create and the following file selector will appear; Browse to where you want your disk image to be put and select Save. Now we have the disk image, we can do a straight copy from drive one to drive two with your Atari via APE, using the virtual disk file instead of a real floppy disk. When you have done it try copying other floppy disks, you can back-up most of your collection this way, although some copy protected disks could be a problem. Now we have a DOS disk to use with our emulator, what about the ROMs? As I mentioned before, although it is possible to use ROMs downloaded with other emulators, the problem with this is that you don't know what you are getting. I am not saying that there are any viruses out there for 8-bits, but it is possible. The only safe way to get a ROM into your emulator is to copy the one hardwired into your real Atari. How to do it? Taking a look at the instructions that came with Atari800Win PLus proved an eye-opener! The following is an extract from the help file; Set bit 7 of port B... Eh? I decided to reach for my copy of Mapping The Atari. It didn't take long to understand what the author meant, but for a beginner it could be difficult. I have written a couple of small Atari BASIC programs to do the donkeywork for you. They are by no means fast but you can see what they are doing, and you will find them easy to alter if you wish to change which drive you want the files sent too. Firstly, let's create an operating system ROM file. Line 30 takes care of setting bit 7 of port B, this makes sure that the rest of the program works okay, otherwise half of the ROM won't be copied. Line 40 is the Disk drive number and filename. By setting it to drive two, this lets you boot into BASIC with drive one using a real 1050 drive, then via APE set-up a folder to use as a PC-Mirror for drive two and the ROM file will be saved there. Having made sure that APE has a second drive set-up mirrored on your PC, type RUN on the Atari and wait. It will take several minutes to run through each part of the memory dump process, but you can see what it happening, an ever-increasing list of numbers will run up the screen until the program has run its course. Now we need a copy of Atari BASIC. This is a much simpler process; line 40 is the disk drive number and filename. I recommend leaving virtual disk settings of APE alone, this way the BASIC ROM will be saved next to the operating system ROM and will be easy to find. Type RUN on the Atari and let the program to create the file - job done! All you need do now is try these ROMs in your Atari emulator as discussed at the beginning of this article, I can tell you the first time I did it, I could not believe that it worked first time, so I did it again. The process should work both ways; you could take a modified ROM from an emulator and put it into a real Atari - that's one to experiment with. Remember old 800XLs came with a buggy version of BASIC, so you may want to use one from the XE series of home computers instead. Now that you have an emulator up and running, next time I will be taking a look at a bit of trouble shooting, but if you are having problems or would just like to know a bit more then please contact me here at MyAtari. m.preston@myatari.co.uk
Useful links
A mass archive of Atari 8-bit software and disk images www.newbreedsoftware.com/xlsearch/ Home of the APE interface and software www.atarimax.com Home of the Atari800Win PLus software (Remember to click on the Union Jack for an English translation) www.a800win.atari-area.prv.pl
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