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-
-
- Documentation for the Apple ][ A2.04 and Atari B1.01 versions of the
-
- 6502 EMULATOR ON THE ATARI ST
- Dec. 31, 1986
-
-
- by Darek Mihocka
-
- The emulators work on any ST with a minimum of 512K, and works
- in any resolution, colour or monochrome. It can be used as a tool to
- learn 6502 machine language, but also, it allows the ST to run Apple
- and Atari software.
-
- Files in the APPLE.ARC file:
-
- - APPLE.TOS (the emulator)
- - EMULATOR.DOC (this file)
- - CONVERT.C (source code for a Apple to ST file conversion)
- - DEMO.BIN (a demo program in Basic)
- - DEMOZP.BIN (zero page locations to make DEMO work)
-
- It is up to the user to create files called APPLSOFT.BIN and
- INTBASIC.BIN by transfering the two languages over to the ST. Both
- occupy memory locations $D000-$FFFF.
-
- Files in the ATARI800.ARC file:
-
- - ATARI800.TOS (the emulator)
- - EMULATOR.DOC (this file)
-
- It is up to the user to create file called OSB.BIN which is a
- binary file in DOS 2.0 format of the memory locations $A000-$FFFF.
-
- DOS 2.0 format is $FF,$FF, start(lo), (hi), end (lo), (hi)
- followed by the actual binary data.
-
- The only software in the machine at load time is the monitor.
- It is similar to the monitor found on Commodore PETs and Apple
- ][s. All commands are one character long, followed by any required
- parameters. The following is a command summary with examples:
-
- : - change contents of memory
- :12 34 56 puts 34 in 12 and 56 in 13
-
- B - boot virtual computer
-
- D - display memory
- D 0000 0028 displays all memory from 00 to 28
-
- G - go to address
- G 1234 starts executing at address 1234
-
- H - hardcopy control
- H1 turns on printer output
- H0 turns it off
-
- I - index of files on disk
-
- L - disassemble memory
- L 3456 disassembles from 3456
-
- M - move memory block
- M 4500 45FF 5600 moves 256 bytes from 4500 to 5600
-
- R - read binary file
- R BASIC loads a file called BASIC into memory
- format of file is $FF,$FF, start, end, data
-
- S - single step
-
- T - trace
-
- V - view video output screen
-
- W - write binary file
- W 1200 19FF TESTFILE
-
- X - exit
-
- A more detailed command summary can be found in the monitor by
- pressing the HELP key.
-
- Using two modems, you can download the operating system from
- the Apple to the ST. If you convert it into a Atari Dos 2.0
- compatible file, that is, a 6 byte header containing $FF,$FF, start
- address, end address, you can load it into the emulator with the R
- command.
-
- To transfer a program you load it into your Apple, and do a hex
- by modem to the ST. What you must transfer is a dump generated by the
- Apple monitor and it must be in the format that appears on the screen
- normally. You can modify the file CONVERT.C to change the format. Then
- compile CONVERT.C to CONVERT.TTP and type in the file name to convert
- and the new filename ending in .BIN.
-
- To see a real demonstration of the emulator, load Applesoft
- Basic by typing "R APPLSOFT" and hit RETURN, then boot it by typing
- "B" and hit RETURN. You will now be in an Apple ][ virtual computer.
- Type "CALL 768". Then load a program, e.g. "R DEMO" and "R DEMOZP".
- Then type "B" and hit return. The virtual computer should now have a
- demo program in memory.
- The editing, Basic, the machine language monitor, and even the
- graphics are similar. Most public domain software can similarly be
- copied over a null cable, and will execute on the emulator.
-
- To exit, you must generate a software interrupt by executing
- a BRK instruction. For example, typing "CALL 40000" will
- accomplish that.
-
- I know that these docs aren't too great but I'm uploading it long
- distance and don't want send over a novel!
-
- - Darek Mihocka MegaBaud ST BBS 416-243-9519
-
-