My light has four 7135, all mounted on the same side as the ATtiny.
You might think this would be more pleasant to work on than the S2+ with the board soldered to the brass pill. You would be wrong. The LED wires are so short and the board is at the bottom of a deep cavity. With the S2+ you can easily unscrew the pill and avoid the tricky business of working in a cavity. I had to unsolder one of the LED wires to be able to tip the board enough to work on it.
It all worked out fine. I used my tiny bit in my dremel to cut the trace to pin 5 of the ATtiny, then clipped onto to board and flashed it. It would not let me reprogram the fuses until after I had flashed the firmware (they were at 0xfd, 0x72), but apparently the erase that was part of the flashing unlocked them and I reprogrammed the fuses after flashing the firmware.
The flashlight is all back together and works fine. I'll note that this light has "only" four 7135, so all the brightnesses will be half of one of the lights with eight of them. This is actually an advantage to my thinking. It doubles battery life at any selected brightness, the moonlight is even better, and the light is plenty bright enough with 1400 mA being delivered.
I say that the moonlight is "better". This is certainly true in theory. Putting it side by side with another light that has eight 7135 and comparing the two moonlight modes, I really cannot tell a difference.
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