FTM Timer PWM output

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con_103

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I am attempting to get and FTM timer outputting a PWM signal to pin 25 on my Teensy 3.2.
But something isn't working.

I am basing my code off an edge aligned example from here
https://www.nxp.com/docs/en/application-note/AN5142.pdf

I read back the PORTA_PCR3 register and got 768 (dec)

Here s a pic of the data sheet, where I got my pin MUX assignment.
Capture.PNG
Do you see any issues? I am new to this embedded programming so I don't really know how to properly troubleshoot. Any info, rules of thumb would be greatly appreciated.
I am using Arduino IDE.

Code: 
void setup() {
  // put your setup code here, to run once:
/* PORTs for FTM0 initialization */
  
  SIM_SCGC6|=0x03000000; //enable FTM0 and FTM0 module clock
  FTM0_CONF=0xC0; //set up BDM in 11
  FTM0_FMS=0x00; //clear the WPEN so that WPDIS is set in FTM0_MODE register
  FTM0_MODE|=0x05; //enable write the FTM CnV register
  FTM0_MOD=1000;
  FTM0_C0SC=0x28; //edge-alignment, PWM initial state is High, becomes low //after match
  FTM0_C1SC=0x28;
  FTM0_COMBINE=0x02; //complementary mode for CH0&CH1 of FTM0
  FTM0_COMBINE|=0x10; //dead timer insertion enabled in complementary mode for //CH0&CH1 of
  
  FTM0_C1V=500;
  FTM0_C0V=500;
  FTM0_C2SC=0x28;
  FTM0_C3SC=0x28;
  FTM0_COMBINE|=0x0200;
  FTM0_COMBINE|=0x1000;
  FTM0_DEADTIME=0x00;
  FTM0_C3V=250;
  FTM0_C2V=250;
  FTM0_CNTIN=0x00;
  FTM0_SC=0x08; //PWM edge_alignment, system clock driving, dividing by 1
  PORTA_PCR3 = PORT_PCR_MUX(3); // FTM0 CH0 - Pin 25
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.println(PORTA_PCR3);
  delay(1);
}
 
You are off to a bad start. Take a look at the T3.2 schematic and the pinout card. You'll see that the chip pin 25 (PTA3) is connected to the teensy bootloader chip. A simpler test of the teensy PWM is to use the Arduino IDE API for PWM (analogWrite). You'll need a logic analyzer or scope to observe the changing values of the PWM pin, or jumper the PWM pin output to a digital pin and count rising edges with attachInterrupt().
Code: 
volatile uint32_t ticks;
void ding() {
  ticks++;
}
void setup() {
  Serial.begin(9600);
  while (!Serial);
  analogWriteFrequency(23, 24000);
  analogWrite(23, 128);   // 50% duty
  attachInterrupt(12, ding, RISING);
}

void loop() {
  delay(1000);
  Serial.println(ticks);
}
The sketch above does PWM on pin 23 @24khz (50% duty), and i jumpered 23 to pin 12 to count rising edges.

If you want to see how the teensy core manipulates the FTM registers, look at source files included with Arduino/Teensy IDE
hardware/teensy/avr/cores/teensy3/pins_teensy.c

T3.2 pin 23 is PTC2 and uses FTM0_CH1
 
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