[solved] AVR133 long delay using cascaded timers

I’m trying to create a long delay by cascading timers via the procedure outlined in Atmel Application Note AVR133. I’ve set timer #1 up to toggle the OCR1A (D9) pin and wired that to the T0 pin (D4) which clocks timer #0. Then I put the arduino to sleep and wait for the timer #0 interrupt to wake it. Or at least that’s what I’m trying to do. The values I’m using should toggle the pin 13 LED at a 1 minute frequency. A much longer delay is easily possible, but I can’t get it t work.

// AVR 133: Atmel Application Note Long Delay Generation 
// T = 2/Fs x T1P x OCR1A x (256 - TCNT0)
// T = 2/16000000x256x7500x(256-6)
// T = 60 or 1 minute
// connect arduino D9 to D4: 
//  T0 = PD4 (Arduino D4 as input)
//  OC1A = PB1 (Arduino D9 as output)
#include <avr/sleep.h>
#include <avr/power.h>

void setup() {
  //set pins
  DDRB |= (1<<PINB1) | (1<<PINB5); //set arduino D9 and D13 as outputs
  PORTB &= ~(1<<PINB1);            //set D9 low
  PORTD &= ~(1<<PIND4);            //set D4 low

  //timer #1 toggles OCR1A on TCNT1=0 in turn toggling T0
  TCCR1A = (1<<COM1A0); //TCCR1A toggle OC1A on compare match
  TCCR1B = 0;
  TCCR1C = 0;
  OCR1A = 7500;       //output compare register on division ratio of 7500
  TIMSK1 = 0;

  //timer #0 fires interrupt when TCNT0=0 waking arduino 
  TCCR0A = 0;
  TCCR0B = 0;
  TIMSK0 = (1<<TOIE0);  //enable timer0 interrupt

void loop() {
  //toggle led
  PORTB ^= (1<<PINB5); //toggle led pin 

  //reset timers
  TCNT0 = 6;
  TCCR0B = (1<<CS00) | (1<<CS01) | (1<<CS02); //external source (t0) rising edge
  TCNT1 = 0UL;
  TCCR1B = (1<<WGM12) | (1<<CS12); //CTC mode 4 and 256 prescaler

  //go to sleep here, wake on interrupt
  //stop timers
  TCCR1B = 0;
  TCCR0B = 0; 

edit: above code now works.