Supported MATLAB Functions with CMSIS Library for ARM Cortex-M Processors

Embedded Coder® Support Package for ARM® Cortex®-M Processors provides a code replacement library (CRL) for common microcontroller software interface standard (CMSIS) functions.

CMSIS CRL supports these processors:

  • Cortex-M0

  • Cortex-M0+

  • Cortex-M3

  • Cortex-M4

  • Cortex-M7

  • Cortex-M33

To improve the simulation speed of your models and performance of the generated code, you can set the model configuration parameters under the Code Generation>Optimization category. For more information on how to set the model parameters, see Model Configuration Parameters: Code Generation Optimization.

Note

  • To get the code replacement, in the code generation configuration settings, set CodeReplacementLibrary to ARM Cortex-M.

  • All CRLs have been tested with CMSIS version 5.9.

Basic Math Operations

Basic Math Operations

Operation Wrappers calling CMSIS function Supported data typesInput/Output specificationsReplaced MATLAB® code
Absolutemw_arm_abs_f32 single

  • Vector or matrix

  • Real inputs

 
abs(a)
Additionmw_arm_add_f32 single

  • Vector and matrix

  • Real and complex inputs

 
a+b
mw_arm_add_q31 fixdt(true,32,31)

  • Vector and matrix

  • Real and complex inputs

 
fimath_q31 = fimath('SumMode','SpecifyPrecision',...
                    'OverflowAction','Saturate',...
                    'RoundingMethod','Floor',...
                    'SumWordLength',32,'SumFractionLength',31);
add(fimath_q31,a,b);
mw_arm_add_q15 fixdt(true,16,15)

  • Vector and matrix

  • Real and complex inputs

 
fimath_q15 = fimath('SumMode','SpecifyPrecision',...
                    'OverflowAction','Saturate',...
                    'RoundingMethod','Floor',...
                    'SumWordLength',16,'SumFractionLength',15);
add(fimath_q15,a,b);
mw_arm_add_q7 fixdt(true,8,7)

  • Vector and matrix

  • Real and complex inputs

 
fimath_q7 = fimath('SumMode','SpecifyPrecision',...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor',...
                   'SumWordLength',8,'SumFractionLength',7);
add(fimath_q7,a,b);
Bias/Offsetmw_arm_bias_1_f32single

  • Real inputs

  • First input must be a scalar.

  • Second input must be a vector or matrix.

 
a+b
mw_arm_bias_1_q31fixdt(true,32,*)

  • Real inputs

  • First input must be a scalar.

  • Second input must be a vector or matrix.

  • Supports different input word lengths.

  • Supports different input fraction lengths.

 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'SumWordLength',32,'SumFractionLength',31,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
add(FimathObj,a,b);
mw_arm_bias_1_q15fixdt(true,16,*) 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'SumWordLength',16,'SumFractionLength',15,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
add(FimathObj,a,b);
mw_arm_bias_1_q7fixdt(true,8,*) 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'SumWordLength',8,'SumFractionLength',7,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
add(FimathObj,a,b);
mw_arm_bias_2_f32single

  • Scalar inputs

  • Vector or matrix

  • Real inputs

  • First input must be a vector or matrix.

  • Second input must be a scalar.

 
a+b
mw_arm_bias_2_q31fixdt(true,32,*)

  • Vector or matrix

  • Real inputs

  • First input must be a vector or matrix.

  • Second input must be a scalar.

  • Supports different input word lengths.

  • Supports different input fraction lengths.

 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'SumWordLength',32,'SumFractionLength',31,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
add(FimathObj,a,b);
mw_arm_bias_2_q15fixdt(true,16,*) 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'SumWordLength',16,'SumFractionLength',15,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
add(FimathObj,a,b);
mw_arm_bias_2_q7fixdt(true,8,*) 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'SumWordLength',8,'SumFractionLength',7,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
add(FimathObj,a,b);
Exponentialmw_arm_vexp_f32single

  • Vector and matrix

  • Real inputs

 
exp(a)
Logarithmmw_arm_vlog_f32single

  • Vector and matrix

  • Real inputs

 
log(a)
Multiplicationmw_arm_mult_f32 single

  • Vector and matrix

  • Real inputs

 
a.*b
mw_arm_mult_q15 fixdt(true,16,*)

  • Vector and matrix

  • Real inputs

  • For multiplication operation, specify one input as a vector and the other as a matrix.

  • Sum of input fraction length must be greater than 15.

  • Fraction length of output must be 15 less than sum of input fraction length.

 
FimathObj = fimath('ProductMode','SpecifyPrecision',...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor',...
                   'ProductWordLength',16,'ProductFractionLength',15);
mpy(FimathObj,a,b);
mw_arm_mult_q7 fixdt(true,8,*)

  • Vector and matrix

  • Real inputs

  • For multiplication operation, specify one input as a vector and the other as a matrix.

  • Sum of input fraction length must be greater than 7.

  • Fraction length of output must be 7 less than sum of input fraction length.

 
FimathObj = fimath('ProductMode','SpecifyPrecision',...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor',...
                   'ProductWordLength',8,'ProductFractionLength',7);
mpy(FimathObj,a,b);
Scale/Gainmw_arm_scale_1_f32single

  • Vector and matrix

  • Real inputs

  • First input is a vector or matrix.

  • Second input is a scalar.

 
a.*b
mw_arm_scale_1_q15fixdt(true,16,*)

  • Vector and matrix

  • Real inputs

  • First input is a vector or matrix.

  • Second input is a scalar.

  • Fraction length of output must be less than the sum of fraction length of inputs.

 
FimathObj = fimath('ProductMode','SpecifyPrecision',...
                   'ProductWordLength',16,...
                   'ProductFractionLength',15,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
mpy(FimathObj,a,b);
mw_arm_scale_1_q7fixdt(true,8,*) 
FimathObj = fimath('ProductMode','SpecifyPrecision',...
                   'ProductWordLength',8,...
                   'ProductFractionLength',7,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
mpy(FimathObj,a,b);
mw_arm_scale_2_f32single

  • Vector and matrix

  • Real inputs

  • First input is a vector or matrix.

  • Second input is a scalar.

  • Fraction length of output must be less than the sum of fraction length of inputs.

 
a.*b
mw_arm_scale_2_q15fixdt(true,16,*) 
FimathObj = fimath('ProductMode','SpecifyPrecision',...
                   'ProductWordLength',16,...
                   'ProductFractionLength',15,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
mpy(FimathObj,a,b);
mw_arm_scale_2_q7fixdt(true,8,*) 
FimathObj = fimath('ProductMode','SpecifyPrecision',...
                   'ProductWordLength',8,...
                   'ProductFractionLength',7,...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor');
mpy(FimathObj,a,b);
Subtraction mw_arm_sub_f32 single

  • Vector and matrix

  • Real and complex inputs

 
a-b
mw_arm_sub_q31 fixdt(true,32,31)

  • Vector and matrix

  • Real and complex inputs

 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor',...
                   'SumWordLength',32,'SumFractionLength',31);
sub(FimathObj,a,b);
mw_arm_sub_q15 fixdt(true,16,15)

  • Vector and matrix

  • Real and complex inputs

 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor',...
                   'SumWordLength',16,'SumFractionLength',15);
sub(FimathObj,a,b);
mw_arm_sub_q7 fixdt(true,8,7)

  • Vector and matrix

  • Real and complex inputs

 
FimathObj = fimath('SumMode','SpecifyPrecision',...
                   'OverflowAction','Saturate',...
                   'RoundingMethod','Floor',...
                   'SumWordLength',8,'SumFractionLength',7);
sub(FimathObj,a,b);
Square rootmw_arm_sqrt_f32 single

  • Vector and matrix

  • Real inputs

 
sqrt(a)
Unary minus/Negatemw_arm_uminus_f32single

  • Vector and matrix

  • Real inputs

 
uminus(a)
mw_arm_uminus_q31fixdt(true,32,*)
mw_arm_uminus_q15fixdt(true,16,*)
mw_arm_uminus_q7fixdt(true,8,*)

Shift Operations

Shift Operations

Operation Wrappers calling CMSIS function Supported data types Input/Output specificationsReplaced MATLAB code
Left shiftmw_arm_shift_31 fixdt(true,32,*)

  • Vector and matrix

  • Real inputs

 
cast(a,'like',b)
mw_arm_shift_15 fixdt(true,16,*)
mw_arm_shift_7 fixdt(true,8,*)

Data Cast Operations

Data Cast Operations

Operation Wrappers calling CMSIS function Supported data types Input/Output specificationsReplaced MATLAB code
Cast float to fixed pointmw_arm_float_to_q15single

  • Vector and matrix

  • Real inputs

 
cast(a,'like',b)
mw_arm_float_to_q7single

  • Vector and matrix

  • Real inputs

Cast q31 to floatmw_arm_q31_to_float fixdt(true,32,31)

  • Vector and matrix

  • Real inputs

Cast q31 to q15mw_arm_q31_to_q15 fixdt(true,32,31)

  • Vector and matrix

  • Real inputs

Cast q31 to q7mw_arm_q31_to_q7 fixdt(true,32,31)

  • Vector and matrix

  • Real inputs

Cast q15 to floatmw_arm_q15_to_float fixdt(true,16,15)

  • Vector and matrix

  • Real inputs

Cast q15 to q31mw_arm_q15_to_q31 fixdt(true,16,15)

  • Vector and matrix

  • Real inputs

Cast q15 to q7mw_arm_q15_to_q7 fixdt(true,16,15)

  • Vector and matrix

  • Real inputs

Cast q7 to floatmw_arm_q7_to_float fixdt(true,8,7)

  • Vector and matrix

  • Real inputs

Cast q7 to q31mw_arm_q7_to_q31 fixdt(true,8,7)

  • Vector and matrix

  • Real inputs

Cast q7 to q15mw_arm_q7_to_q15fixdt(true,8,7)

  • Vector and matrix

  • Real inputs

Complex Math Operations

Complex Math Operations

Operation Wrappers calling CMSIS function Supported data typesInput/Output specificationsReplaced MATLAB code
Complex conjugatemw_arm_cmplx_conj_f32 single

  • Vector and matrix

  • Complex inputs

 
conj(a)
Complex-by-complex multiplicationmw_arm_cmplx_mult_cmplx_f32 single

  • Vector and matrix

  • Both inputs must be complex

 
a.*b
Complex-by-real multiplicationmw_arm_cmplx_mult_real_f32 single

  • Vector and matrix

  • Real and complex inputs

  • One input must be complex and the other must be real.

 
a.*b

Logical Operations

Logical Operations

Operation Wrappers calling CMSIS functionSupported data typesInput/Output specificationsReplaced MATLAB code
Logical ANDmw_arm_and_uint32

  • uint32

  • fixdt(false,32,*)

  • Vector and matrix

  • Both inputs must be uint32 or fixdt(false,32,*).

  • Both inputs must have same fraction length.

 
bitand(a,b)
mw_arm_and_uint16

  • uint16

  • fixdt(false,16,*)

  • Vector and matrix

  • Both inputs must be uint16 or fixdt(false,16,*).

  • Both inputs must have same fraction length.

mw_arm_and_uint8

  • uint8

  • fixdt(false,8,*)

  • Vector and matrix

  • Both inputs must be uint8 or fixdt(false,8,*).

  • Both inputs must have same fraction length.

Logical ORmw_arm_or_uint32

  • uint32

  • fixdt(false,32,*)

  • Vector and matrix

  • Both inputs must be uint32 or fixdt(false,32,*).

  • Both inputs must have same fraction length.

 
bitor(a,b)
mw_arm_or_uint16

  • uint16

  • fixdt(false,16,*)

  • Vector and matrix

  • Both inputs must be uint16 or fixdt(false,16,*).

  • Both inputs must have same fraction length.

mw_arm_or_uint8

  • uint8

  • fixdt(false,8,*)

  • Vector and matrix

  • Both inputs must be uint8 or fixdt(false,8,*).

  • Both inputs must have same fraction length.

Logical NOTmw_arm_not_uint32

  • uint32

  • fixdt(false,32,*)

  • Vector and matrix

 
bitcmp(a)
mw_arm_not_uint16

  • uint16

  • fixdt(false,16,*)

  • Vector and matrix

mw_arm_not_uint8

  • uint8

  • fixdt(false,8,*)

  • Vector and matrix

Logical XORmw_arm_xor_uint32

  • uint32

  • fixdt(false,32,*)

  • Vector and matrix

  • Both inputs must be uint32 or fixdt(false,32,*).

  • Both inputs must have same fraction length.

 
bitxor(a,b)
mw_arm_xor_uint16

  • uint16

  • fixdt(false,16,*)

  • Vector and matrix

  • Both inputs must be uint16 or fixdt(false,16,*).

  • Both inputs must have same fraction length.

mw_arm_xor_uint8

  • uint8

  • fixdt(false,8,*)

  • Vector and matrix

  • Both inputs must be uint8 or fixdt(false,8,*).

  • Both inputs must have same fraction length.

Matrix Operations

Matrix Operations

Operation Wrappers calling CMSIS functionSupported data typesInput/Output specificationsReplaced MATLAB code
Matrix multiplicationmw_arm_mat_mult_f32

  • single

  • Vector and matrix

 
a*b
Complex matrix multiplicationmw_arm_mat_cmplx_mult_f32

  • single

  • Vector and matrix

  • Complex values

 
a*b
Matrix transposemw_arm_trans_f32

  • single

  • Matrix

  • Real inputs

 
  • transpose(a)
  • a'
  • ctranspose(a)
  • a.'
mw_arm_trans_q31

  • fixdt(true,32,*)

mw_arm_trans_q15

  • fixdt(true,16,*)

mw_arm_trans_q7

  • fixdt(true,8,*)

mw_arm_mat_cmplx_trans_f32

  • single

  • Matrix

  • Complex inputs

 
  • transpose(a)
  • a'
mw_arm_mat_cmplx_trans_q31

  • fixdt(true,32,*)

mw_arm_mat_cmplx_trans_q15

  • fixdt(true,16,*)

Fourier Transform Operations

Fourier Transform Operations

MATLAB FunctionSupported Function SignaturesInput specificationsProperty specificationsEquivalent CMSIS Functions
fft

Y = fft(X)

Y = fft(X, n)

Y = fft(X, n, dim)

  • Real or Complex Values

  • Multichannel Input (Multiple columns)

  • single data type

Transform Length n:

  • Real Input: n must be in the range[9 2048] U {4096}-{16}.

  • Complex Input: n must be in the range[5 2048] U {4096}-{8}.

Dimension to operate along dim: dim must be a compile time constant.

  • arm_cfft_f32

  • arm_rfft_fast_init_f32

  • arm_rfft_fast_f32

Wrapper functions, each with an mw_ prefix bridge the library interface.

ifft

X = ifft(Y)

X = ifft(Y, n)

X = ifft(Y, n, dim)

X = ifft(__, symflag)

  • Real or Complex Values

  • Multichannel Input

  • single data type

Transform Length n: Minimum length is 8.

Dimension to operate along dim: dim must be a compile time constant.

Symmetric type symflag: non-symmetric (default)

  • arm_cfft_f32

  • arm_rfft_fast_init_f32

  • arm_rfft_fast_f32

Wrapper functions, each with an mw_ prefix bridge the library interface.

fft2

Y = fft2(X)

Y = fft2(X, m, n)

  • Real or Complex Values

  • Multichannel Input

  • single data type

Number of transform rows m:

  • Minimum length is 8 when input is real.

  • Minimum length is 4 when input is complex.

Number of transform rows n:

  • Minimum length is 8 when input is real.

  • Minimum length is 4 when input is complex.

  • arm_cfft_f32

  • arm_rfft_fast_init_f32

  • arm_rfft_fast_f32

Wrapper functions, each with an mw_ prefix bridge the library interface.

ifft2

X = ifft2(Y)

X = ifft2(Y, m, n)

X = ifft2(__, symflag)

  • Complex Values

  • Multichannel Input

  • single data type

Number of transform rows m:

  • Minimum length is 8

Number of transform rows n:

  • Minimum length is 8

Symmetric type symflag: non-symmetric (default)

  • arm_cfft_f32

  • arm_rfft_fast_init_f32

  • arm_rfft_fast_f32

Wrapper functions, each with an mw_ prefix bridge the library interface.

fftn

Y = fftn(X)

Y = fftn(X, sz)

  • Real or Complex Values

  • Multichannel Input (Multiple columns)

  • single data type

Length of transform dimension sz: Each sz element must have:

  • Minimum value 8 when input is real

  • Minimum value 4 when input is complex

  • arm_cfft_f32

  • arm_rfft_fast_init_f32

  • arm_rfft_fast_f32

Wrapper functions, each with an mw_ prefix bridge the library interface.

ifftn

X = ifftn(Y)

X = ifftn(Y, sz)

X = ifftn(__, symflag)

  • Complex Values

  • Multichannel Input

  • single data type

Length of transform dimension sz: Each sz element must have:

  • Minimum value is 8

  • arm_cfft_f32

  • arm_rfft_fast_init_f32

  • arm_rfft_fast_f32

Wrapper functions, each with an mw_ prefix bridge the library interface.