user11529: I've got a MAX7456 chip and I am using this (this is the unmodified one) library with it. 
There's a sketch inside the examples folder (Max7456WriteTable) that I need to get to work to update the character table.
I modified three lines and then I got really stuck as I do not know how to continue. This is the modified one.
In file included from Max7456Write.ino:2:0:
/tmp/build4608284042510222737.tmp/sketch/Max7456WriteTable.h:29:69153: warning: narrowing conversion of '243' from 'int' to 'const char' inside { } is ill-formed in C++11 [-Wnarrowing]

This happens for every item in the array. But that is not the only problem. (I'll skip a few hundred lines)
/tmp/build8855411239666100148.tmp/sketch/Max7456Write.cpp.o: In function `setup':
/home/t/Max7456Write.ino:13: undefined reference to `Max7456::Max7456(unsigned char)'
/home/t/Max7456Write.ino:19: undefined reference to `Max7456::activateOSD(bool)'
/home/t/Max7456Write.ino:44: undefined reference to `Max7456::getCARACFromProgMem(char const*, unsigned char, unsigned char*)'
/home/t/Max7456Write.ino:46: undefined reference to `Max7456::sendCharacter(unsigned char const*, unsigned char, unsigned char)'
collect2: error: ld returned 1 exit status
Error compiling.

It takes a huge amount of time for it to abort the compilation.

user2881: If I change prog_uchar to unsigned char in both max7456.h and max7456.cpp the hello world example sketch compiles. 
In Max7456WriteTable change
Max7456::getCARACFromProgMem(i,currentChar); //Because the table is too big for ram memory

osd->sendCharacter(currentChar,i); //We send currentChar at address i.

to 
Max7456::getCARACFromProgMem(tableOfAllCharacters, i,currentChar); //Because the table is too big for ram memory

osd->sendCharacter(currentChar,i, 0); //We send currentChar at address i.

0 is probably the wrong value, but at least it compiles.

11529: <p>I've got a MAX7456 chip and I am using <a href="https://www.dropbox.com/s/3cp4am1f271odcm/max7456.tar?dl=1" rel="nofollow">this (this is the unmodified one)</a> library with it. 
There's a sketch inside the examples folder (Max7456WriteTable) that I need to get to work to update the character table.</p>

<p>I modified three lines and then I got really stuck as I do not know how to continue. <a href="https://www.dropbox.com/s/sljvyngc27zver4/max7456_new.tar?dl=1" rel="nofollow">This</a> is the modified one.</p>

<pre><code>In file included from Max7456Write.ino:2:0:
/tmp/build4608284042510222737.tmp/sketch/Max7456WriteTable.h:29:69153: warning: narrowing conversion of '243' from 'int' to 'const char' inside { } is ill-formed in C++11 [-Wnarrowing]
</code></pre>

<p>This happens for every item in the array. But that is not the only problem. (I'll skip a few hundred lines)</p>

<pre><code>/tmp/build8855411239666100148.tmp/sketch/Max7456Write.cpp.o: In function `setup':
/home/t/Max7456Write.ino:13: undefined reference to `Max7456::Max7456(unsigned char)'
/home/t/Max7456Write.ino:19: undefined reference to `Max7456::activateOSD(bool)'
/home/t/Max7456Write.ino:44: undefined reference to `Max7456::getCARACFromProgMem(char const*, unsigned char, unsigned char*)'
/home/t/Max7456Write.ino:46: undefined reference to `Max7456::sendCharacter(unsigned char const*, unsigned char, unsigned char)'
collect2: error: ld returned 1 exit status
Error compiling.
</code></pre>

<p>It takes a huge amount of time for it to abort the compilation.</p>
 2881: <p>If I change <code>prog_uchar</code> to <code>unsigned char</code> in both max7456.h and max7456.cpp the hello world example sketch compiles. </p>

<p>In Max7456WriteTable change</p>

<pre><code>Max7456::getCARACFromProgMem(i,currentChar); //Because the table is too big for ram memory

osd-&gt;sendCharacter(currentChar,i); //We send currentChar at address i.
</code></pre>

<p>to </p>

<pre><code>Max7456::getCARACFromProgMem(tableOfAllCharacters, i,currentChar); //Because the table is too big for ram memory

osd-&gt;sendCharacter(currentChar,i, 0); //We send currentChar at address i.
</code></pre>

<p><code>0</code> is probably the wrong value, but at least it compiles.</p>
