User Manual

Page 39
7.1 Board Specific SEMA Functions
7.1.1 Voltages
The BMC of the ETX-BT implements a voltage monitor and samples several onboard voltages.
The voltages can be read by calling the SEMA function “Get Voltages”. The function returns a 16-
bit value divided into high-byte (MSB) and low-byte (LSB).
ADC Channel Voltage Name Voltage Formula [V]
0 CPU-Vcore (MSB<<8 + LSB) x 3.3 / 1024
1 GFX-Vcore (MSB<<8 + LSB) x 3.3 / 1024
2 +V1.05S (MSB<<8 + LSB) x 3.3 / 1024
3 Vmem (MSB<<8 + LSB) x 3.3 / 1024
4 +V1.0V (MSB<<8 + LSB) x 3.3 / 1024
5 +V3.3V (MSB<<8 + LSB) x 1.1 x 3.3 / 1024
6 +VIN (MSB<<8 + LSB) x 6.000 x 3.3 / 1024
7 MAIN CURRENT Use Main Current Function
7.1.2 Main Current
The BMC of the ETX-BT implements a current monitor. The current can be read by calling the
SEMA function “Get Main Current”. The function returns four 16-bit values divided in high-byte
(MSB) and low-byte (LSB). These 4 values represent the last 4 currents drawn by the board. The
values are sampled every 250ms. The order of the 4 values is NOT in chronological order. Access
by the BMC may increase the drawn current of the whole system. In this case, there are still 3
samples not influenced by the read access.
Main Current = (MSB_n<<8 + LSB_n) x 8.06mA