Interrupts R5#

Software User Model#

The interrupt triggers the ISR_Control function (in isr.c) and the ADC conversion in the PL. The trigger can be synchronized with the PWM (two- and three-level) modules or the axi2tcm data mover. The interrupt trigger is defined in uz_global_configuration.h by assigning a value to Interrupt_ISR_source_user_choice.

//chose here which of the above interrupt trigger you want to use:
#define Interrupt_ISR_source_user_choice    0
Table 6 Trigger sources for interrupt#

#

Define name

Interrupt trigger

0

Interrupt_2L_max_min

Two-Level PWM Module at minimum and maximum value of the triangular carrier

1

Interrupt_2L_min

Two-Level PWM Module at minimum value of the triangular carrier

2

Interrupt_2L_max

Two-Level PWM Module at maximum value of the triangular carrier

3

Interrupt_3L_start_center

Three-Level PWM Module at minimum and maximum value of the triangular carrier

4

Interrupt_3L_start

Three-Level PWM Module at minimum value of the triangular carrier

5

Interrupt_3L_center

Three-Level PWM Module at maximum value of the triangular carrier

6

axi2tcm_write_done

Triggers when axi2tcm data mover signals write_done

Structure of the Interrupt#

        graph TD
  A[Interrupt_ISR_source_user_choice] -->|Sets interrupt source| B(Initialize_ISR)
  B -->|Mux for ADC trigger source| D[Trigger source of ADC in PL]
  B -->|Rpu_GicInit| E[Trigger source of ISR_Control]

Fig. 56 Usage of Interrupt_ISR_source_user_choice in source code#

        graph LR
    PWM2L --> Interrupt
    PWM3L --> Interrupt
    Interrupt --> Concat_interrupts
    Concat_interrupts --> mux_axi
    mux_axi --> ADC_trigger_conversion
    Concat_interrupts --> R5_Interrupt

Fig. 57 Signal flow in PL of interrupt and trigger ADC#

Structure in the PL#

The Interrupt module consists of:

  • mux_axi: chose source of ADC conversion trigger

  • delay_trigger: adds delay to the ADC conversion trigger

  • vio_interrupt: manually trigger delay by Vivado hardware manager for debugging

  • adc_delay: vio to set delay of delay_trigger

../../../_images/pl_interrupt_module.png

Fig. 58 PL module of the interrupt structure.#

In Vivado, the signals connected to pl_ps_irq0 are assigned an interrupt ID starting at XPS_FPGA0_INT_ID for bit 0 and increasing with each additional signal. In our project, the Interrupt_vector is directly connected to pl_ps_irq0. With this logic, the interrupt IDs are assigned in isr.h. Note that XPS_FPGAx_INT_ID is defined in xparameters_ps.h.

Trigger of ADC Conversion#

In some applications, the ADC conversion needs to be delayed relative to the trigger from the PWM module. This can be the case if you are using an IGBT, where the delay introduced by the driver and the IGBT itself are not negligible. To ensure that the ADC sampling does not occur while switching, the delay can be added in PL. At the moment this is done with a VIO (Virtual IO) in the Hardware Manager in Vivado.