r8a77850anbg Renesas Electronics Corporation., r8a77850anbg Datasheet - Page 1510

• Manufacturer Part Number: r8a77850anbg
• Description: Renesas 32-bit Risc Microcomputer Superh? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

29. User Break Controller (UBC)
29.4
By using the user break debugging support function, the branch destination address can be
modified when the CPU accepts the user break request. Specifically, setting the UBDE bit of
break control register CBCR to 1 allows branching to the address indicated by DBR instead of
branching to the address indicated by the [VBR + offset]. Figure 29.2 shows the flowchart of the
user break debugging support function.
Rev.1.00 Jan. 10, 2008 Page 1480 of 1658
REJ09B0261-0100
Hardware operations
User Break Debugging Support Function
Debugging program
(STC instruction)
Figure 29.2 Flowchart of User Break Debugging Support Function
R15 ← SGR
PC ← DBR
Yes
EXPEVT ← Exception code
(CBCR.UBDE == 1)
&& (user break)?
Exception
No
Exception handling routine
PC ← VBR + vector offset
INTEVT ← Interrupt code
Exception operation ends
Exception/interrupt/trap?
Execute RTE instruction
Exception/interrupt
Reset exception?
SR.MD ← B'1
SR.RB ← B'1
SR.BL ← B'1
is generated
SGR ← R15
SPC ← PC
SSR ← SR
PC ← SPC
SR ← SSR
No
Interrupt
Yes
TRA ← TRAPA (imm)
Trap
PC ← H'A000 0000
EXPEVT ← H'160