ADLINK CoreExpress-ECO2 - Manual (Page 34)

4.28 Set Backlight PWM
This command sets the duty of Backlight control output. The value of the PWM also controls the
Backlight enable output. In case of PWM=0, the Backlight enable output will go inactive.
START SMC_addr ACK command ACK length ACK PWM_value ACK STOP
Table 4.28.1 SMC receiver format of the Set Backlight PWM Command Code
ITEM DESCRIPTION
START SM-bus start condition
SMC_addr 01010000b = 0x50 (8-bit, write access to SMC)
ACK SM-bus acknowledge condition generated by receiver
command 0x80 = “Set Backlight PWM” Command code
length 0x01 = Length of this Command
PWM_value Duty setting (0-255)
STOP SM-bus stop condition
Table 4.28.2 Explanation of Table 4.28.1
4.29 Get Backlight PWM
This command reads the current duty of the Backlight control output.
START SMC_addr ACK command ACK length ACK PWM_value ACK STOP
Table 4.29.1 SMC receiver format of the Set Backlight PWM Command Code
ITEM DESCRIPTION
START SM-bus start condition
SMC_addr 01010000b = 0x50 (8-bit, write access to SMC)
ACK SM-bus acknowledge condition generated by receiver
command 0x80 = “Set Backlight PWM” Command code
length 0x01 = Length of this Command
PWM_value Duty setting (0-255)
STOP SM-bus stop condition
Table 4.29.2 Explanation of Table 4.29.1