Re: Resolution Output compare
124 code for 50us
1 code for 50e-6 /124 = 403 e-9. Resolution is 403 ns
Duty cycle in percent is the raw value devided by 124.
If you compute with your simulink model a duty cycle whose values are taken within 0 and 1, then you need to multiply by 124, convert result to uint16 and connect that result to the OC block input up (duty cycle) or down (duty cycle). Note that it is possible to use the OC1max variable within simulink to perform such scaling.
FYI, The max time you provide allows the tool to determine the best setting for internal counter frequency that will provide the finest resolution which comply with this maximum time constraint.