Tinkering with a Kospet ROCK

Le led driver current control implementation is described like this in the 3603 datasheet :

LED current range 3.2 to 204.8 mA
LED current resolution 6 Bits
...
The device has one internal current DAC 3bits output current control.
The output current control though register 0x0Bbit2:bit0for phase1
to phase3.

And in the driver :

// LED Driver current
HRS_LEDDR_MSB : 3,
PS1_LEDDR_MSB : 7,
LEDDR_LSB : 7,
...
dev.writeByte(0x0b, c.PS1_LEDDR_MSB<<4 | c.HRS_LEDDR_MSB);
dev.writeByte(0xc4, c.EXTPD_SEL<<7 | (c.LEDDR_LSB&0x07)<<4 | 0x0f);

Look vaguely consistent. Shame that the 0xC4 register isn't documented (among others).