User`s guide

A.3.4 – Rear connections

The DSP can generate a pulse train with variable period (actually, its duty cycle) - this

method, PWM (Pulse-Width Modulation) is the DSPs main form of signal output.

At the boards back, we have 24 PWM outputs (12 unique), which can be measured by an

oscilloscope. The table below show how the rear connections are placed and denoted.

Rear connections

PWM is best introduced by looking at yet another sample program, Example_281xEvPwm.

Particularly interesting are the two functions init_eva() and init_evb(). In the code segment

below, we take a closer look at init_eva()

void init_eva()

{

// EVA Configure T1PWM, T2PWM, PWM1-PWM6

// Initalize the timers

// Initalize EVA Timer1

EvaRegs.T1PR = 0x0FFF; // Timer1 period

EvaRegs.T1CMPR = 0x3C00; // Timer1 compare

EvaRegs.T1CNT = 0x0000; // Timer1 counter

// TMODE = continuous up/down

// Timer enable

// Timer compare enable

EvaRegs.T1CON.all = 0x1042;