PINK no longer receive through serial input pin

My PINK is no longer able to receive variable values through the serial input pin.
I can modify variables with the factory page and the values stays there as long as power is connected but the vaiables will not be overwritten each time the BS writes to the PINK.
I have checked the power, no problems, no resets, I tried a different BS and I also checked RX-pin on PINK with scope and find no errors.
I can access the PINK from the network without any problem, upload and download.
The BS updates the variables every twenty seconds or so.
The PINK has been running for almost a year, seven days a week, with no problems until this happend. Now it's only displaying NA where variables should be.
Looks like a serial input issue on the PINK, anyone have any ideas here?
I can modify variables with the factory page and the values stays there as long as power is connected but the vaiables will not be overwritten each time the BS writes to the PINK.
I have checked the power, no problems, no resets, I tried a different BS and I also checked RX-pin on PINK with scope and find no errors.
I can access the PINK from the network without any problem, upload and download.
The BS updates the variables every twenty seconds or so.
The PINK has been running for almost a year, seven days a week, with no problems until this happend. Now it's only displaying NA where variables should be.
Looks like a serial input issue on the PINK, anyone have any ideas here?
Comments
Edit:
Back from work reading Parallax' own datasheet on PINK, page 5 about variables:
I am using variables in the RAM area only (20-99), not writing to one single of the flash-memory variables. I can't find any information that these RAM locations could be worn out. Sorry I didn't mention what variable location I am using, in my first post.