Proximity Sensor - Maxim44000

Steps to getting the Maxim chip working:

Follow the steps given in the tutorial link below.

http://pdfserv.maximintegrated.com/en/an/UG5483.pdf

This starts with sdk rather than vivado because it includes a hidden block design/code for each of the maxim chips. Once you have completed the tutorial and the FPGA is programmed, then you can use gtk term to read the output of the chip. The instructions below are for installing and using gtk term.

 The following link gives a three step process on how to install gtkterm.
http://pkgs.org/centos-6/epel-i386/gtkterm-0.99.5-11.el6.i686.rpm.html

In the first step, this link is provided:
http://dl.fedoraproject.org/pub/epel/6/i386/

Open the previous link and look for:

epel-release-6-8.noarch.rpm

Click on this link and it will download. Then in the downloads folder, or at the bottom of your web browser, click the file to install it.

Then go to the terminal and type the following:

sudo yum install gtkterm

Directions to use gtkterm are in Sven's blog:
http://svenand.blogdrive.com/archive/173.html#.VWh9l9jbJ9A

At the beginning of the blog, it talks about permissions. Following these steps can help with that:
To check for the permissions, open a terminal and type:
          cd ..
          cd ..  (to move all the way out)
          cd dev (must be in this directory)
          ls -l ttyAMC0  (checks the permission)
If the permission is not crw-rw-rw, then type:
          sudo chmod 666 ttyACM0

Then we are able to follow the steps in Sven's blog.

Then once you run the program, gtk term should look something like the picture below. This picture should the fluctuations in the Proximity value as I moved my hand closer to the sensor and then farther away and repeating this motion.

I am still unsure of what these values mean but the datasheet (http://datasheets.maximintegrated.com/en/ds/MAX44000.pdf) states that a photodiode array inside the IC converts light to a current which is then processed into a digital value. I think this digital value is an 8 bit number because 2^8 = 256 and the highest value that was outputted when my hand was directly on top of the sensor was 253. This is just an idea and I need to look into this more.

253  fd    11111101

208  d0    1101000

125  7d    01100001

97    61    01100001