Hi all,<br><br>I have a number of driver related function calls that I would like to add as Primitive functions to yhc and yhi. For yhi (yhc\src\runtime\BCKernel) I have added definitions to Runtime.c and WrapPrimitive.c, in order to define and wrap stuff like&nbsp; &quot;void display_string(void)&quot; where the function is declared in a 
display.h/display.c file&nbsp; (this code controls the LCD display of the NXT).<br><br>So far I think I have this yhi part covered. My question is about where these primitives are made known to the compiler so I can make display_string visible to yhc programs. After adding this line to 
Primitive.hs yhc hangs...<br><br>----------------------------------------------------------------------------------------------------<br>-- NXT Display<br>----------------------------------------------------------------------------------------------------
<br>foreign import fastccall display_string :: CString -&gt; IO ()<br><br><br>I just noticed the following files seem to have something todo with things:<br><br>C:\YHC_OLD_SOURCES\yhc_again\yhc\src\packages\yhc-base-1.0\YHCPrimitive.hs
<br><br>C:\YHC_OLD_SOURCES\yhc_again\yhc\src\compiler\Prim.hs<br>C:\YHC_OLD_SOURCES\yhc_again\yhc\src\compiler\PrimCode.hs<br clear="all"><br>C:\YHC_OLD_SOURCES\yhc_again\yhc\src\compiler98\Prim.hs<br>
C:\YHC_OLD_SOURCES\yhc_again\yhc\src\compiler98\PrimCode.hs<br clear="all"><br><br>Which changes I need to make before recompiling YHC? Thanks in advance.&nbsp; :)<br><br>Cheers,<br>-- <br>&lt;/Alexis&gt;