I found the thread: Help: Keyboard input problem?
In: Dosbox General
Just to let you know, I upgraded to Windows 10 and reinstalled the latest DOSBOx and the keyboard in it works perfectly now. If you still want to try the keyboard with an earlier OS see below...
I typed in keyb us103 437. I don't know if that was the original layout setting. however I discovered that if I map the ' key as itself, typing shift before it yields a double quotation! In other words: in keyboard mapper (ctrl-f1) click on ' which is just left of the \ key. then click on add. then type ' again. click save. close. then type shift-' to enter ".
Thank you so much Qbix! You made my day! I'll post this in the other thread also.
For other not working keys try mapping them as themselves possibly. if you don't know where a character is try to search for the characters you need by first mapping every one that is not a-z and press shift before typing them as it could be a capital toggle like " was.
first be sure to try mapping (typing a key after add) without holding the shift key
i also found if you set usescancodes=false, pressing a key will spill out all it's characters
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I have to add, now, with more experience, when I was trying to type a tilda ~ that it was possible only after pasting it into the console. I.e. I used notebook to make a text file with a tilda ~ in it and then opened it in Dosbox, copied and pasted it, and then i was able to type it. That is, of course, after mapping it as itself. Note: i did this in Turbo C++ with a file extension of .cpp