Log of Problems and Solutions

SOLVED 2-8-2012 Jitter and Flashing of image

PROBLEM: On front illuminated image it was observed that the images had a flashing on the first column and that there was a pixel jitter.

CAUSE: The pipeline in the fCRIC must first be purge before we get the real data from the CCD. This is done in state 4 of the readout state machine. After state 4 the readot goes to state 5 where it starts saving data. The state machine was entering state 5 while in the middle of the data transfers started in state 4.

SOLUTION: Extend the end time of state 4 from 96 ticks to 245 ticks. This will prevent the system from entering state 5 until the fCRICs are done sending out their data. Since this state is only used for 6 pixles it will not have a signifigant inpact on the total readout time.

PROBLEM: It was possible through software to apply more than 5V to the buffer chips. This allows developers and users to issue a "Self-Destruct" command. This has been tested out and verified to work. (Too soon to joke?)

SOLUTION: Initially there was a Software fix, but a hardware solution should was implemented and was included in the final 12 boards.

NOT SOLVED YET - Buffer Chips should not recieve more than +5V

PROBLEM It is possible through software to apply more than 5V to the buffer chips. This allows developers and users to issue a "Self-Destruct" command. This has been tested out and verified to work. (Too soon to joke?)

SOLUTION Software protection has been implemented in the GUI, but a hardware solution should be implemented.