/** ISR to handle software SPI transmission and reception */
ISR(TIMER1_COMPA_vect, ISR_BLOCK)
{
+ /* Check if rising edge (output next bit) or falling edge (read in next bit) */
if (!(PINB & (1 << 1)))
{
if (SoftSPI_Data & (1 << 7))
DDRB &= ~((1 << 1) | (1 << 2));
PORTB &= ~((1 << 0) | (1 << 3));
+ /* Must re-enable rescue clock once software ISP has exited, as the timer for the rescue clock is
+ * re-purposed for software SPI */
ISPTarget_ConfigureRescueClock();
}
}