4.7.2. Floating-point Context Control Register

The FPCCR register sets or returns FPU control data. See the register summary in Table 4.58 for its attributes. The bit assignments are:

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Table 4.60. FPCCR bit assignments

BitsNameFunction
[31]ASPEN

Enables CONTROL.FPCA setting 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.

0

Disable CONTROL.FPCA setting on execution of a floating-point instruction.

1

Enable CONTROL.FPCA setting on execution of a floating-point instruction.

[30]LSPEN
0

Disable automatic lazy state preservation for floating-point context.

1

Enable automatic lazy state preservation for floating-point context.

[29:9]-Reserved.
[8]MONRDY
0

DebugMonitor is disabled or priority did not permit setting MON_PEND when the floating-point stack frame was allocated.

1

DebugMonitor is enabled and priority permits setting MON_PEND when the floating-point stack frame was allocated.

[7]-Reserved.
[6]BFRDY
0

BusFault is disabled or priority did not permit setting the BusFault handler to the pending state when the floating-point stack frame was allocated.

1

BusFault is enabled and priority permitted setting the BusFault handler to the pending state when the floating-point stack frame was allocated.

[5]MMRDY
0

MemManage is disabled or priority did not permit setting the MemManage handler to the pending state when the floating-point stack frame was allocated.

1

MemManage is enabled and priority permitted setting the MemManage handler to the pending state when the floating-point stack frame was allocated.

[4]HFRDY
0

Priority did not permit setting the HardFault handler to the pending state when the floating-point stack frame was allocated.

1

Priority permitted setting the HardFault handler to the pending state when the floating-point stack frame was allocated.

[3]THREAD
0

Mode was not Thread Mode when the floating-point stack frame was allocated.

1

Mode was Thread Mode when the floating-point stack frame was allocated.

[2]-Reserved.
[1]USER
0

Privilege level was not user when the floating-point stack frame was allocated.

1

Privilege level was user when the floating-point stack frame was allocated.

[0]LSPACT
0

Lazy state preservation is not active.

1

Lazy state preservation is active. Floating-point stack frame has been allocated but saving state to it has been deferred.


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