2. Programming Model
Rev.1.00 Jan. 10, 2008 Page 33 of 1658
REJ09B0261-0100
2.2.4 Control Registers (1) Status Register (SR)
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
BIt:
0111000000000000
MD RB BL
FD M Q IMASK S T
Initial value:
RR/WR/WR/WRRRRRRRRRRRR
R/W:
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
BIt:
0000000011110000
Initial value:
R/W R R R R R R/W R/W R/W R/W R/W R/W R R R/W R/W
R/W:
Bit Bit Name
Initial
Value R/W Description
31 — 0 R Reserved
For details on reading/writing this bit, see General
Precautions on Handling of Product.
30 MD 1 R/W Processing Mode
Selects the processing mode.
0: User mode (Some instructions cannot be executed
and some resources cannot be accessed.)
1: Privileged mode
This bit is set to 1 by an exception or interrupt.
29 RB 1 R/W Privileged Mode General Register Bank Specification
Bit
0: R0_BANK0 to R7_BANK0 are accessed as general
registers R0 to R7 and R0_BANK1 to R7_BANK1 can
be accessed using LDC/STC instructions
1: R0_BANK1 to R7_BANK1 are accessed as general
registers R0 to R7 and R0_BANK0–R7_BANK0 can
be accessed using LDC/STC instructions
This bit is set to 1 by an exception or interrupt.
28 BL 1 R/W Exception/Interrupt Block Bit
This bit is set to 1 by a reset, a general exception, or an
interrupt.
While this bit is set to 1, an interrupt request is masked.
In this case, this processor enters the reset state when
a general exception other than a user break occurs.