Question

TRAP is an interrupt in 8085. Which one of the following statements is true about the TRAP
1. It is level triggered
2. It is negative edge triggered
3. It is positive edge triggered
4. It is both positive and negative edge triggered

Answer 1

Correct Answer - Option 3 : It is positive edge triggered

Edge Triggered Interrupts:

1. TRAP

2. RST 7.5

Level-Triggered Interrupts:

1. TRAP

2. RST 5.5

3. RST 6.5

4. INTR

TRAP is both level and positive edge sensitive it means that TRAP makes a low to high transition and remain high until it is acknowledged.

Since the TRAP input has the highest priority, it is used for catastrophic events such as power failure, parity errors, and other events that require immediate attention.

Interrupt	Priority	Trigger	Mask	Vectored address
TRAP (RST 4.5)	1 (Highest)	Edge and Level	Non-maskable	0024 H
RST 7.5	2	Edge	Maskable	003C H
RST 6.5	3	Level	Maskable	0034 H
RST 5.5	4	Level	Maskable	002C H
INTR	5 (Lowest)	Level	Maskable	0000 to 0038 H