TilEm on MacOS

TilEm is a Linux emulator for certain TI graphing calculators including the TI-83 and TI-84 series. This is more or less how I got TilEm running on my Snow Leopard MacOS system. I'm no expert; suggestions welcome.

Install MacPorts.
Using MacPorts, install gtk2
```
sudo port install gtk2
```
Download TilEm.

Unzip and build it:

tar xvfz tilem-0.973.tar.gz
cd tilem-0.973
./configure
make

TilEm really just emulates the calculator hardware; it depends on an actual TI calculator ROM to act like a calculator. Here's one way to get one:
1. Download the TI-83 Plus SDK from here.
2. Download and install wine. MacPorts has a wine port but at this writing it does not work with Snow Leopard so instead I used this handbuilt and hand-tweaked version.
  This is how you would install under MacPorts:
```
sudo port install wine
  
```
3. Using wine, open the downloaded SDK (named 83psdk_setup.exe). This should open the Windows installer; when it asks where to install, make sure it goes to a Mac directory, not a native Windows directory. (Of course, instead of using wine, you could also install the SDK on a Windows machine and just copy the ROMs over to the Mac.)
4. Copy the .clc files from where they got installed to where the tilem binary lives:
```
cp sdkdir/Exe/*.clc tilemdir/bin
  
```
Start X-Windows
Start tilem from tilemdir/bin
```
./tilem
```
This seems to copy the ROMs to a standard place: ~/.TilEm/ti83p. (If you see the TilEm logo on the screen, you have to turn the calculator on before it works!)
If it works, install it:
```
sudo make install
```
Run it from a command window with the command tilem. Make sure X11 is running first.

Extra credit tweak: White background instead of gray

TilEm tries a bit too hard to emulate the thing accurately. One thing I don't like is the gray screen, especially if I want screen shots for printing. So I modified tilemdir/src/tilem/gui/screen.c this way:

308,309c308,309
< = (0xbd * i) / (NGRAYS - 1);
< iris[NGRAYS*3 - i - 1] = (0xb5 * i) / (NGRAYS - 1);
---
>   = (0xff/*bd*/ * i) / (NGRAYS - 1);
>   iris[NGRAYS*3 - i - 1] = (0xff/*b5*/ * i) / (NGRAYS - 1);

Jon Dreyer • Math tutor • Computer Science tutor
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