CHAPTER 13 SYSTEM DOWN

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This chapter describes the system down functions performed by the RI600V4.

13.1 Outline

When the event that cannot be recovered while the RI600V4 is operating occurs, the system down is caused and the system down routine is invoked.

13.2 User-Own Coding Module

The system down routine must be implemented as user-own coding module.

Note The System down routine (_RI_sys_dwn__) which is provided by the RI600V4 as a sample file is implemented in the boot processing file "resetprg.c".

13.2.1 System down routine (_RI_sys_dwn__)

The following shows the basic form of the system down routine. The system down routine must not return.

#include "kernel.h" /*Standard header file definition*/ #include "kernel_id.h" /*Header file generated by cfg600*/ void _RI_sys_dwn__ ( W type, VW inf1, VW inf2, VW inf3 ); /*Prototype declaration*/ void _RI_sys_dwn__ ( W type, VW inf1, VW inf2, VW inf3 ) { /* ......... */ while(1); }

Note The function name of the system down routine is "_RI_sys_dwn__".

- Stack
The system down routine uses the system stack.

- Service call
The system down routine must not issue service calls.

- PSW register when processing is started

Table 13-1 PSW Register When System Down Routine is Started

Bit	Value	Note
I	0
IPL	- type < 0 : Undefined - type >= 0 : Same before system down	Do not lower IPL more than the start of processing.
PM	0	Supervisor mode
U	0	System stack
C, Z, S, O	Undefined
Others	0

13.2.2 Parameters of system down routine

- type == -1 (Error when a kernel interrupt handler ends)

Table 13-2 Parameters of System Down Routine (type == -1)

inf1	inf2	inf3	Description
E_CTX (-25)	2	Undefined	PSW.PM == 1 (user mode) when a kernel interrupt handler ends.
	3	Undefined	PSW.IPL > kernel interrupt mask level when a kernel interrupt handler ends.
	5	Undefined	The system is in the CPU locked state when a kernel interrupt handler ends.

- type == -2 (Error in ext_tsk)

Table 13-3 Parameters of System Down Routine (type == -2)

inf1	inf2	inf3	Description
E_CTX (-25)	1	Undefined	The ext_tsk is called in the non-task context.
	4	Undefined	PSW.IPL > kernel interrupt mask level when ext_tsk is called.

- type == -3 (Unlinked service call issued)

Table 13-4 Parameters of System Down Routine (type == -3)

inf1	inf2	inf3	Description
E_NOSPT (-9)	Undefined	Undefined	Unlinked service call is issued.

Note Refer to "2.6.1 Service call information files and "-ri600_preinit_mrc" compiler option".

- type == -16 (Undefined relocatable vector interrupt)

Table 13-5 Parameters of System Down Routine (type == -16)

inf1	inf2	inf3
- "-U" option is not specified for cfg600 Undefined - "-U" option is specified for cfg600 Vector number	PC, which is pushed to the stack by CPU's interrupt operation	PSW, which is pushed to the stack by CPU's interrupt operation

- type == -17 (Undefined fixed vector/exception vector interrupt)

Table 13-6 Parameters of System Down Routine (type == -17)

inf1	inf2	inf3
- "-U" option is not specified for cfg600 Undefined - "-U" option is specified for cfg600 Vector number	PC, which is pushed to the stack by CPU's interrupt operation	PSW, which is pushed to the stack by CPU's interrupt operation

- type > 0 (Issuing vsys_dwn, ivsys_dwn from application))
0 and a negative type value is reserved by the RI600V4. When calling vsys_dwn, ivsys_dwn from application, use positive type value.

Table 13-7 Parameters of System Down Routine (type > 0)

inf1	inf2	inf3
Value specified for vsys_dwn, ivsys_dwn