On 21.05.2021 13:56, R.Wieser wrote:
Herbert,

But in real DOS, the "copy com1 file" should work.

You got me there I'm afraid, I used the DOS w98 ran on. And although "copy
com1 file" /looks/ to be working there, it , just as "type com1", does not
know when to stop. Ctrl-C-ing outof it causes the file to be empty. :-\

How many characters did you send? Maybe it is written to the file only if
an internal buffer is full. But in DOS you can use .com programs. Just a
few bytes of code is necessary to copy bytes from com1 to stdout (terminate
if a special character is received or after maybe 1k byte is received).
Use debug or directly enter an ascii binary using the keyboard.