Board Specific Sema Functions; Voltages; Main Current; Bmc Status - ADLINK Technology COM Express Express-BL User Manual

5.1.

Board Specific SEMA Functions

5.1.1.

Voltages

The BMC of the Express-BL 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).
5.1.2.

Main Current

The BMC of the Express-BL 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.
5.1.3.

BMC Status

This register shows the status of BMC controlled signals on the Express-BL.
ADC Channel Voltage Name
0 Not used
1 +V3.3V
2 +V1.05S
3 +V3.3V
4 +VMEM
5 +V5.0V
6 +VIN
7 (MAIN CURRENT)
Main Current = (MSB_n<<8 + LSB_n) x 8.06mA
Status Bit
0
1
2
3
4
5
6
7
Voltage Formula [V]
(MSB<<8 + LSB) x 1.1 x 3.3 / 1024
(MSB<<8 + LSB) x 3.3 / 1024
(MSB<<8 + LSB) x 1.1 x 3.3 / 1024
(MSB<<8 + LSB) x 3.3 / 1024
(MSB<<8 + LSB) x 1.833 x 3.3 / 1024
(MSB<<8 + LSB) x 6.000 x 3.3 / 1024
Use Main Current Function
Signal
WDT_OUT
LVDS_VDDEN
LVDS_BKLTEN
BIOS_MODE
POSTWDT_DISn
SEL_BIOS
BIOS_DIS0n
BIOS_DIS1n
Express-BL
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