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I have a story about executable text-file and it goes like this: In 1990 I got Atari Portfolio from liquidation sale in Sweden. Copyright was expired so there

I have a story about executable text-file and it goes like this: In 1990 I got Atari Portfolio from liquidation sale in Sweden. Copyright was expired so there were no romcard, which contained various tools to program the bloody thing. It was an empty MSDOS-machine without DEBUG or anything. All I could do was to copy 7 bit ASCII-characters to a file from the keyboard. After few days, or maybe weeks, I managed to construct small ASCII TXT-file, which, when renamed to EXE-file, executed a loop, which read and interpreted hexadecimal code from keyboard and executed this piece of code at <CR>. This was the gateway and bootstrap to everything else. And yes: I was now in Finland. So there was no other Atari Portfolio owner anywhere nearby from whom I could have borrowed this romcard.

em-bee 6y ago
could you share the rest of the story please? what does "copy from keyboard" mean? was there a way to type numbers to produce any 7bit sequence? and with that you wrote a program that could read hex (which was easier to type than raw 7bit code)? so you wrote the initial program in raw machinecode? not as a script that would be interpreted? and then what did you type in hex? the whole contents of the romcard? and you got that from where? you had a printout of that?
- timonoko 6y ago
  This is what I was trying to do: c:\> echo ABCDEFG > file.txt c:\> ren file.txt file.exe c:\> file.exe DOSBOX: Exit to error: Illegal GRP4 Call 5 Now. Imagine that you study very hard raw machine code and find a new string (replacing ABCDEFG), which constitute valid EXE-header and a piece of code, which does not cause error and does something useful. And useful thing here was to interpret letter-pairs in the string as hexadecimal numbers, so you then can write any program you want. Did this help any?
  - em-bee 6y ago
    yes, you are confirming what i guessed. so you were able to type out the initial program only with the keys on the keyboard? how did you find what to type? and then once you had the hex-reader, where did you get the hexdump to type in? which programs did you create this way?
    - timonoko 6y ago
      No thank you kindly. I give up. This was 31 years ago and it was once-only issue. Who cares. Remembered however that COM-files were the simple ones. EXE-headers were more complicated. But quite obviously I made a program that read stuff from serial port. And once you had ZMODEM you could copy rest of standard MSDOS command set from anywhere. The machine was truly empty, the was only hardwired COMMAND.COM running.
      - em-bee 6y ago
        well, that wasn't obvious to me. thank you. so you did have access to the right executables, just no direct way to get them into the machine. i only dabbled with old unix workstations. the oldest one being a machine from 1989 running apollo domain OS. and i remember booting an AIX workstation into some kind of rescue mode and using ed to fix config files (fstab probably) to allow it to boot.

em-bee 6y ago

could you share the rest of the story please? what does "copy from keyboard" mean? was there a way to type numbers to produce any 7bit sequence? and with that you wrote a program that could read hex (which was easier to type than raw 7bit code)? so you wrote the initial program in raw machinecode? not as a script that would be interpreted? and then what did you type in hex? the whole contents of the romcard? and you got that from where? you had a printout of that?

timonoko 6y ago
This is what I was trying to do: c:\> echo ABCDEFG > file.txt c:\> ren file.txt file.exe c:\> file.exe DOSBOX: Exit to error: Illegal GRP4 Call 5 Now. Imagine that you study very hard raw machine code and find a new string (replacing ABCDEFG), which constitute valid EXE-header and a piece of code, which does not cause error and does something useful. And useful thing here was to interpret letter-pairs in the string as hexadecimal numbers, so you then can write any program you want. Did this help any?
- em-bee 6y ago
  yes, you are confirming what i guessed. so you were able to type out the initial program only with the keys on the keyboard? how did you find what to type? and then once you had the hex-reader, where did you get the hexdump to type in? which programs did you create this way?
  - timonoko 6y ago
    No thank you kindly. I give up. This was 31 years ago and it was once-only issue. Who cares. Remembered however that COM-files were the simple ones. EXE-headers were more complicated. But quite obviously I made a program that read stuff from serial port. And once you had ZMODEM you could copy rest of standard MSDOS command set from anywhere. The machine was truly empty, the was only hardwired COMMAND.COM running.
    - em-bee 6y ago
      well, that wasn't obvious to me. thank you. so you did have access to the right executables, just no direct way to get them into the machine. i only dabbled with old unix workstations. the oldest one being a machine from 1989 running apollo domain OS. and i remember booting an AIX workstation into some kind of rescue mode and using ed to fix config files (fstab probably) to allow it to boot.