Video Out/VGA Display Skipping Every Other X Pixel

Hey, so I'm using a De1-SoC and programming in Assembly using the the Nios II instruction set found here: https://www.altera.com/content/dam/altera-www/global/en_us/pdfs/literature/hb/nios2/n2cpu_nii51017.pdf

So I was just experimenting with the video out pixel buffer (at memory located 0x8000000) and tried to create a screen that was just entirely white. I looped through each pixel and coloured each one white but I am getting vertical lines that are not being coloured in. I have provided pictures as well as screenshots of the documentation I used to create the image, my source code, and the output on my VGA monitor.

http://www.alteraforum.com/forum/attachment.php?attachmentid=11935&stc=1 Vertical columns not being printed white

http://www.alteraforum.com/forum/attachment.php?attachmentid=11937&stc=1 Video Out Documentation - 1

http://www.alteraforum.com/forum/attachment.php?attachmentid=11938&stc=1 Video Out Documentation - 2

http://www.alteraforum.com/forum/attachment.php?attachmentid=11936&stc=1 Video Out Documentation - 3

Any help is greatly appreciated! Cheers