The COM generated by NASM is not byte exact to the original TURBO.COM due to different codes for the same opcode instructions but it worked.
It worked and the next step was to turn the generated MASM code in NASM. Quite some time ago I found a tool to turn the original COM of TP 3.01 into its source file including comment.
I'll have a look at it anyway, you never know what interesting bits can be found. It only supports lines of 80 bytes and that is not what I have in mind.