CHAPTER 7 INTERRUPT/EXCEPTION PROCESSING FUNCTION
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User’s Manual U15195EJ5V0UD
7.2.1 Operation
If a non-maskable interrupt is generated, the CPU performs the following processing, and transfers control to the
handler routine.
(1) Saves the restored PC to FEPC.
(2) Saves the current PSW to FEPSW.
(3) Writes exception code 0010H to the higher halfword (FECC) of ECR.
(4) Sets the NP and ID bits of the PSW and clears the EP bit.
(5) Sets the handler address (00000010H) corresponding to the non-maskable interrupt to the PC, and transfers
control.
The servicing configuration of a non-maskable interrupt is shown in Figure 7-1.
Figure 7-1. Servicing Configuration of Non-Maskable Interrupt
PSW.NP
FEPC
FEPSW
ECR.FECC
PSW.NP
PSW.EP
PSW.ID
PC
Restored PC
PSW
0010H
1
0
1
00000010H
1
0
NMI input
Non-maskable interrupt request
Interrupt servicing
Interrupt request held pending
INTC
acknowledged
CPU processing
Содержание PD703114
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