Applicable Systems
DVP
AH500
AS300
C2000
MS300
Symptoms
An illegal instruction was found in an interrupt service routine. The ISR cannot be executed.
Possible Causes
- Instruction not supported in interrupt context
- ISR contains instructions that modify system state unsafely
Troubleshooting Steps
- Step 1: Locate the illegal instruction in the interrupt service routine
Illegal instruction is identified - Step 2: Remove or replace the instruction with an ISR-safe alternative
Program compiles without error
How to Reset
To reset: Replace the illegal instruction in the ISR, then recompile and download.
Source: Delta DVP PLC Programming Manual, Delta Electronics
Category: PLC & VFD