
FPU Registers
179
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Cortex-M4 Peripherals
2.7.2 FPCC Register (Offset = 0xF34) [reset = 0xC0000000]
Floating-Point Context Control (FPCC)
The FPCC register sets or returns FPU control data.
FPCC is shown in
and described in
.
Return to
Figure 2-34. FPCC Register
31
30
29
28
27
26
25
24
ASPEN
LSPEN
RESERVED
R/W-0x1
R/W-0x1
R-0x0
23
22
21
20
19
18
17
16
RESERVED
R-0x0
15
14
13
12
11
10
9
8
RESERVED
MONRDY
R-0x0
R/W-0x0
7
6
5
4
3
2
1
0
RESERVED
BFRDY
MMRDY
HFRDY
THREAD
RESERVED_3
USER
LSPACT
R-0x0
R/W-0x0
R/W-0x0
R/W-0x0
R/W-0x0
R-0x0
R/W-0x0
R/W-0x0
Table 2-52. FPCC Register Field Descriptions
Bit
Field
Type
Reset
Description
31
ASPEN
R/W
0x1
Automatic State Preservation Enable
When set, enables the use of the FRACTV bit in the CONTROL
register on execution of a floating-point instruction.
This results in automatic hardware state preservation and
restoration, for floating-point context, on exception entry and exit.
NOTE: Two bits control when FPCA can be enabled: the ASPEN bit
in the Floating-Point Context Control (FPCC) register and the
DISFPCA bit in the Auxiliary Control (ACTLR) register.
30
LSPEN
R/W
0x1
Lazy State Preservation Enable
When set, enables automatic lazy state preservation for floating-
point context.
29-9
RESERVED
R
0x0
8
MONRDY
R/W
0x0
Monitor Ready
When set, DebugMonitor is enabled and priority permits setting
MON_PEND when the floating-point stack frame was allocated.
7
RESERVED
R
0x0
6
BFRDY
R/W
0x0
Bus Fault Ready
When set, BusFault is enabled and priority permitted setting the
BusFault handler to the pending state when the floating-point stack
frame was allocated.
5
MMRDY
R/W
0x0
Memory Management Fault Ready
When set, MemManage is enabled and priority permitted setting the
MemManage handler to the pending state when the floating-point
stack frame was allocated.
4
HFRDY
R/W
0x0
Hard Fault Ready
When set, priority permitted setting the HardFault handler to the
pending state when the floating-point stack frame was allocated.
3
THREAD
R/W
0x0
Thread Mode
When set, mode was Thread Mode when the floating-point stack
frame was allocated.
2
RESERVED
R
0x0