TX19A Datasheet, PDF (132/491 Pages) Toshiba Semiconductor – 32Bit TX System RISC

Chapter 9 Exception Handling
Exception detection
1
EXL (Status [1])?
0
YES
Instr. In branch
NO
delay slot？
･ BD (Cause[31]) ← 1
･ EPC ← PC of jump or
branch instr.
･ BD (Cause[31]) ← 0
･ EPC ← PC
YES
Maskable
NO
Interrupt？
* If BEV=0 & IV=0
PC ← 0x8000_0180
If BEV=0 & IV=1
PC ← 0x8000_0200
If BEV=1 & IV=0
PC ← 0xBFC0_0380
If BEV=1 & IV=1
PC ← 0xBFC0_0400
If BEV=0
PC ← 0x8000_0180
If BEV=1
PC ← 0xBFC0_0380
* BEV = Status [22]
IV = Cause [23]
CE (Cause[29:28]) ← Fault Cop #
ExcCode (Cause[6:2]) ← Exception code
EXL (Status[1])
←1
Branch to the exception handler
Figure 9-1 General Exception Processing
The CE field consists of the Cause register bit 28 and 29 is only valid when a Coprocessor Unusable
exception occurred.
9-2