Problem with SPI eeprom

Hi everyone!

I’m trying to write to and read from an AT93C46D eeprom using an Arduino UNO but for some reason the output I’m getting is not what I expect.

The eeprom has a data structure of 128 words of 8 bits each and I’m trying to write 10000010 to each word. When reading back the data however I get 11000001.
If I write all zeros I get 10000000 when reading the eeprom. So it seems that the MSB is always 1 for some reason.
I’m probably making a stupid mistake but I can’t seem to find it, any help is greatly appreciated!

My .ino file is attached to this post.
Datasheet: http://www.atmel.com/images/atmel-5193-seeprom-at93c46d-datasheet.pdf

AT93c46d.ino (1.21 KB)