There is an in-depth article covering several Samsung devices in the SamsungSerial page
| Device | I/O voltage | ID<->GND | SOC TX | SOC RX | switch | Comments |
|---|---|---|---|---|---|---|
| I9300 | 1.8V1 | 619kOhms | D- | D+ | It gives a shell once Replicant has booted | |
| Nexus S | 150 kOhm | FSA9480 | ||||
| Galaxy Nexus | ||||||
| Optimus Black | N/A2 |
1 Measured between USB GND and USB VCC
fn2. Code is required to use the switch as you need to configure both the MUIC and DP3T switch