This demo code shows how to synchronize the PWM signals with another internal timer or an off-chip source. It allows you to achieve slower PWM frequencies than those that can be achieved with internal clocks as well as that multiple modules and multiple chips can be synchronized to each other.
The idea is the following:
The QTMR generates a PWM signal (external clock signal) which is routed through the XBAR to clocking the eFlexPWM, and at the same, the external clock signal is routed to an IO PAD in the first MCU. In a second MCU, an IO PAD is routed through the XBAR to clocking the eFlexPWM (see Figure 1).
Figure 1
The demo code (only MCU1 part so far) can me tested using the SDK for EVKB-IMXRT1050 v2.14.0.
Probe the PWM signals using an oscilloscope:
- - At J24-1 GPIO_AD_B0_03 XBAR1_INOUT17 (QTMR PWM signal)
- - At J24-6 GPIO_SD_B0_00 FLEXPWM1_PWM0_A
- - At J24-3 GPIO_SD_B0_01 FLEXPWM1_PWM0_B
Please remember weld resistors 0Ω at R280 R281.
