Black Spot PCB Modifications
Buck converter modification
The initial design had a short between the 5V supply and ground. To alter the PCB to match the correct schematic, lift pins 5-8 of FET1. Connect a wire between the cathode of D1 to all lifted pins of FET1 as shown in Figure D.1.
Flash select line
The flash select line must be connected to processor flag PF2. This was initially connected to another line. To fix this cut the track running to pin 1 of FL SH1. Rewire pin 1 of FL SH1 to the via to the left of the R11 designator as shown in Figure D.2.
Image data bus modification
The image data bus must be rewired to allow 8 bit reads of the image sensor to be initi- ated without the possibility of the bright parts of the image producing a banding effect caused by the least significant bits resetting to zero. This operation is difficult and involves rewiring each image sensor data line so that the effect is a logic roll right by 2 bits. The schematic given in ppendix is the revised schematic and shows the modified image data bus. To modify the PCB to match the schematic requires cutting tracks on the top and
bottom of the board.