C2000 Synchronization of ePWM modules with external signal

Hello everyone, I am trying to use an external signal to synchronize 4 ePWM (ePWM1, ePWM2, ePWM3 and ePWM4) modules together, however I have not been able to make it work. Modules ePWM1, ePWM2 and ePWM3 are configured as UP/DOWN with TBPRD = 5000 (achieving 20 kHz period) and ePWM4 is also configured in UP/DOWN mode, however TBPRD = 50000 (achieving 2 kHz). I would like to use a signal connected to GPIO40 as an external SYNC to the ePWM modules. The signal is 2 kHz. How am I supposed to configure the ePWM Blocks in Simulink??? BTW: I have configured GPIO40 als SYNCI inthe Hardware settings tab.

I have also noticed that Simulink is not setting the EPWMSYNCINSEL register in the generated code.....

I am using a TMS320F28388D ControlCard

Thanks!