Texas Instruments TMS320C67X/C67X+ DSP - Manual (Page 400)

Overview
5-5 Interrupts SPRU733
5.1.1.4 Interrupt Acknowledgment (IACK) and Interrupt Number (INUMn)
The IACK and INUMn signals alert hardware external to the C6000 that an
interrupt has occurred and is being processed. The IACK signal indicates that
the CPU has begun processing an interrupt. The INUMn signal (INUM3−
INUM0) indicates the number of the interrupt (bit position in the IFR) that is
being processed. For example:
INUM3 = 0 (MSB)
INUM2 = 1
INUM1 = 1
INUM0 = 1 (LSB)
Together, these signals provide the 4-bit value 0111, indicating INT7 is being
processed.