User's Manual

Table Of Contents
R01UH0823EJ0110 Rev.1.10 Page 275 of 1852
Nov 30, 2020
RX23W Group 14. Exception Handling
14.6 Return from Exception Handling Routine
Executing the instruction listed in Table 14.3 at the end of the corresponding exception handling routine restores the
values of the program counter (PC) and processor status word (PSW) that were saved on the stack or in the control
registers (BPC and BPSW) immediately before the exception handling sequence.
14.7 Priority of Exception Events
The priority of exception events is listed in Table 14.4. When multiple exceptions are generated at the same time, the
exception with the highest priority is accepted first.
Table 14.3 Return from Exception Handling Routine
Exception Instruction for Return
Undefined instruction exception RTE
Privileged instruction exception RTE
Access exception RTE
Floating-point exception RTE
Reset Return is impossible
Non-maskable interrupt Prohibited
Interrupt Fast interrupt RTFI
Other than above RTE
Unconditional trap RTE
Table 14.4 Priority of Exception Events
Priority Exception Event
High
Low
1Reset
2 Non-maskable interrupt
3 Interrupt
4 Instruction access exception
5 Undefined instruction exception
Privileged instruction exception
6 Unconditional trap
7 Operand access exception
8 Floating-point exception