26 get main current – ADLINK CoreExpress-ECO2 User Manual
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4.26 Get Main Current
This command reads 4 values representing the last 4 currents drawn by the board. The values are
sampled every 250ms. The order of the 4 values is NOT in relationship to the time. The access to the
SMC may increase the drawn current of the whole system. In this case, you still have 3 samples
without the influence of the read access.
The returned values must be calculated by the user application into a current. Please look at the
board technical manual chapter “LEMT functions” for the equation to calculate the returned value
into a current.
START
SMC_addr
ACK command
ACK START (Repeat)
SMC_addr+1
ACK
length
ACK(C) MSB_byte1
ACK(C) LSB_byte1
ACK(C) ...
MSB_byte4
ACK(C)
LSB_byte4
ACK(C) STOP
Table 4.26.1 SMC transmitter format of the Get Main Current Command Code
ITEM
DESCRIPTION
START
SM-bus start condition
SMC_addr
0x50 (8-bit)
ACK
SM-bus acknowledge condition generated by receiver
command
0x69 = “Get Main Current” Command code
length
0x08 = 8 Bytes data length
MSB byte n
LSB byte n
4 samples of 16-Bit data value of Main Current (n=1..4)
STOP
SM-bus stop condition