Hatsune Mike
Champion
Got a Dangun Feveron board in, which had flickering graphics and garbage on the bottom of the screen.
(the camera has nicely shown three frames here thanks to a rolling shutter - the left is a correct frame, the center is garbled, and the right is correct)
Someone in the past had replaced the ROMs (but included the originals), and the custom ICs have all been reflowed.
From observing it it became clear that every other frame had correct graphics, while the next was garbled crap.
My first instincts were that one of the two sprite framebuffer DRAMs were bad (smack dab in the middle of the board, next to the SPATTR 013 IC)
I desoldered those two J-lead chips, and transplanted some donor ones from a parts PCB (a dead power instinct 2).
Board booted perfectly, with working graphics.
(the camera has nicely shown three frames here thanks to a rolling shutter - the left is a correct frame, the center is garbled, and the right is correct)
Someone in the past had replaced the ROMs (but included the originals), and the custom ICs have all been reflowed.
From observing it it became clear that every other frame had correct graphics, while the next was garbled crap.
My first instincts were that one of the two sprite framebuffer DRAMs were bad (smack dab in the middle of the board, next to the SPATTR 013 IC)
I desoldered those two J-lead chips, and transplanted some donor ones from a parts PCB (a dead power instinct 2).
Board booted perfectly, with working graphics.
