Mitsubishi Electric M32R Series User Manual page 105

4
[EIT Processing]
(1) Saving SM, IE, and C bits
The SM, IE, and C bits of the PSW register are saved to their backup bits-the BSM, BIE,
and BC bits.
BSM
BIE
BC
(2) Updating SM, IE, and C bits
The SM, IE, and C bits of the PSW register are updated as shown below.
SM
IE
C
(3) Saving PC
The content (always word boundary) of the PC register is saved to the BPC register.
(4) Branching to the EIT vector entry
Control branches to the address H'0000 0010 in the user space. This is the last operation
performed in hardware preprocessing by the M32R/E.
(5) Jumping from the EIT vector entry to the user-created handler
The M32R/E executes the "BRA" instruction written at address H'0000 0010 of the EIT
vector entry by the user to jump to the start address of the user-created handler. The
system break interrupt can only be used when some fatal event has occurred to the
system. Also, this interrupt must be used on condition that after processing by the SBI
handler, control will not return to the program that was being executed when the system
break interrupt occurred.
← SM
← IE
← C
← 0
← 0
← 0
4-17
4.9 Interrupt Processing
Ver.0.10
EIT