I have this code
Repeat getKey(9)
0~K
If R<14
If getKey(47)
Output(R,0,"A"
R+1~R
1~{GDB3+1}
47~K
End
While getKey(K)=1
End
End
End
In case it wasn't self explanatory, ~ is the Sto>.

Now, what should happen if you repeatedly press math is that you get an output that it "AAAAAAAAAAAAAAA"

But what is really happening is a display like "Annnnnnnnnnnn" with the "n"s italicized.

It works properly if i leave out the line with the GDB write, or if i don't add a number to the pointer.

I am new to Axe, so most i just figured out by trial and error, but i can't firgure this one out  

I don't get it. Why would you need GBD3? You aren't doing anything with it.

Hmm, he did never declare GDB3. I think he's overwriting the $32 for A with $01 which is indeed n(I think it's $32)

If you declared it as Data()→GDB3, then the behaviour of your program is normal
Here is your program, untouched:

Data()→GDB3
[??]
.I think you have declared some data inbetween, or
.maybe some code before that loop declared some data
.Else, the output would not be "Annnnn" but "AAnnnnn"
Repeat getKey(9)
0~K
If R<14
If getKey(47)
Output(R,0,"A"
R+1~R
1→{GDB3+1}
47~K
End
While getKey(K)=1
End
End
End

Here is how Axe translates it:

Data()→GDB3
[??]
"A"→Str0
Repeat getKey(9)
0~K
If R<14
If getKey(47)
Output(R,0,Str0)
R+1~R
1→{GDB3+1}
47~K
End
While getKey(K)=1
End
End
End

Which is basically the same as this, since there is nothing in the Data():

[??]→GDB3
"A"→Str0
Repeat getKey(9)
0~K
If R<14
If getKey(47)
Output(R,0,Str0)
R+1~R
1→{GDB3+1}
47~K
End
While getKey(K)=1
End
End
End

And now, Str0=GDB3+1, so when you do 1→{GDB3+1}, it replaces the A by a n, which is why you got the n