Supervisor Mode
3-6
ADSP-BF535 Blackfin Processor Hardware Reference
service routine is interruptible, the return address is stored on the stack.
For this case, the address can be found by popping the value from the
stack. Once
RETx
has been loaded, the
RTx
instruction can be issued.
Note the stack pop is optional. The service routine becomes
non-interruptible, because the return address is not saved on the
stack.
The processor remains in User mode until one of these events occurs:
• An interrupt, NMI, or exception event invokes Supervisor mode.
• An emulation event invokes Emulation mode.
• A reset event invokes the Reset state.
Supervisor Mode
The processor services all interrupt, NMI, and exception events in Super-
visor mode.
Table 3-4. Return Instructions That can Invoke User Mode
Current Process Activity
Return Instruction to Use
Execution Resumes at Address
in This Register
Interrupt Service Routine
RTI
RETI
Exception Service Routine
RTX
RETX
Nonmaskable Interrupt Service
Routine
RTN
RETN
Emulation Service Routine
RTE
RETE
Summary of Contents for ADSP-BF535 Blackfin
Page 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Page 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Page 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Page 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Page 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Page 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Page 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Page 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Page 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...