14
32000D–04/2011
AVR32
R - Java register remap
When this bit is set, the addresses of the registers in the register file is dynamically changed.
This allows efficient use of the register file registers as a stack. For more details, see
chapter 3..
The R bit is cleared at reset. Undefined behaviour may result if this bit is modified by the user.
T - Scratch bit
This bit is not set or cleared implicit by any instruction and the programmer can therefore use
this bit as a custom flag to for example signal events in the program. This bit is cleared at reset.
L - Lock flag
Used by the conditional store instruction. Used to support atomical memory access. Automati-
cally cleared by rete. This bit is cleared after reset.
Q - Saturation flag
The saturation flag indicates that a saturating arithmetic operation overflowed. The flag is sticky
and once set it has to be manually cleared by a csrf instruction after the desired action has been
taken. See the Instruction set description for details.
V - Overflow flag
The overflow flag indicates that an arithmetic operation overflowed. See the Instruction set
description for details.
N - Negative flag
The negative flag is modified by arithmetical and logical operations. See the Instruction set
description for details.
Z - Zero flag
The zero flag indicates a zero result after an arithmetic or logic operation. See the Instruction set
description for details.
C - Carry flag
The carry flag indicates a carry after an arithmetic or logic operation. See the Instruction set
description for details.
2.11
System registers
The system registers are placed outside of the virtual memory space, and are only accessible
cal locations is IMPLEMENTATION DEFINED, but a maximum of 256 locations can be
addressed with the dedicated instructions. Some of the System Registers are altered automati-
cally by hardware.
The reset value of the System Registers are IMPLEMENTATION DEFINED.