Get Started with MATLAB to SystemC Workflow Using the Command Line Interface
This example shows how to use the HDL Coder™ command-line interface to generate SystemC code from MATLAB® code, including floating-point to fixed-point conversion.
SystemC code generation using the command-line interface has the following basic steps:
Set up the high-level synthesis (HLS) tool path for SystemC code generation by using the function
fixptcoder configuration object.
hdlcoder configuration object.
Set configuration object parameters.
codegencommand to generate SystemC code.
The HDL Coder command-line interface can use two coder configuration objects with the
codegen command. The
fixpt coder configuration object configures the floating-point to fixed-point conversion of your MATLAB code. The
hdl coder configuration object configures SystemC code generation and programming options.
The example code implements a simple symmetric finite impulse response (FIR) filter and its test bench. Using this example, you can configure floating-point to fixed-point conversion and generate SystemC code.
Set up the FIR model and test bench for this example.
Create Floating-Point to Fixed-Point Conversion Configuration Object
If your design already uses fixed-point types and functions, then you can skip the fixed-point conversion step.
To perform floating-point to fixed-point conversion, you need a
fixpt configuration object.
fixpt configuration object and specify your test bench name.
fixptcfg = coder.config('fixpt'); fixptcfg.TestBenchName = 'mlhdlc_sfir_tb';
Fixed-Point Conversion Type Proposal Options
The code generator can propose fixed-point types based on your choice of either word length or fraction length. These two options are mutually exclusive.
Base the proposed types on a word length of
fixptcfg.DefaultWordLength = 24; fixptcfg.ProposeFractionLengthsForDefaultWordLength = true;
Alternatively, you can base the proposed fixed-point types on fraction lengths. The following code configures the coder to propose types based on a fraction length of
fixptcfg.DefaultFractionLength = 10; fixptcfg.ProposeWordLengthsForDefaultFractionLength = true;
The code generator increases the simulation data range on which it bases its fixed-point type proposal by the safety margin percentage. For example, the default safety margin is
4, which increases the simulation data range used for fixed-point type proposal by
fixptcfg.SafetyMargin = 10;
The code generator runs the test bench with the design before and after a floating-point to fixed-point conversion. You can enable simulation data logging to plot the quantization effects of the new fixed-point data types.
Enable data logging in the
fixpt configuration object:
fixptcfg.LogIOForComparisonPlotting = true;
Numeric Type Proposal Report
Configure the code generator to start the type proposal report once the fixed-point types have been proposed:
fixptcfg.LaunchNumericTypesReport = true;
Create SystemC Code Generation Configuration Object
To generate SystemC code, you must create an
hdl configuration object and set your test bench name:
hdlcfg = coder.config('hdl'); hdlcfg.TestBenchName = 'mlhdlc_sfir_tb';
Target Language and Synthesis Tool
To generate SystemC code, specify the target language as
SystemC and the synthesis tool as
hdlcfg.TargetLanguage = 'SystemC'; hdlcfg.SynthesisTool = 'Cadence Stratus';
Generation of SystemC Test Bench Code
Configure the code generator to generate a SystemC test bench from your MATLAB® test bench:
hdlcfg.GenerateHDLTestBench = true;
Simulation of the Generated SystemC Code
If you want to simulate your generated SystemC code, you must also configure the code generator to generate a SystemC test bench.
hdlcfg.SimulateGeneratedCode = true;
Synthesis Tool for Generated SystemC Code
You can synthesize your generated SystemC code by using the synthesis tool Cadence Stratus. Configure the code generator to use this tool.
hdlcfg.SynthesizeGeneratedCode = true;
Run SystemC Code Generation
Now that you have your
hdl configuration objects set up, run the
codegen command to perform floating-point to fixed-point conversion and generate SystemC code:
codegen -float2fixed fixptcfg -config hdlcfg mlhdlc_sfir -report
SystemC Code Generation Report
At the MATLAB command line window, you can check the code generation report by clicking
The code generation report helps you to:
Debug code generation issues and verify that your MATLAB code is suitable for code generation.
View generated SystemC code.
Access additional reports like a conformance report.
See how the code generator determines and propagates type information for variables and expressions in your MATLAB code.
To view a MATLAB function in the code pane, click the name of the function in the MATLAB Source pane. In the code pane, when you pause on a variable or expression, a tooltip displays information about its size, type, and complexity.
Only Cadence Stratus is supported as the high level synthesis tool. Cadence Stratus supports only point to point (p2p) communication for SystemC code generation.
Generating SystemC code that runs on multiple threads is not supported.
Real data types and Systems objects are not supported for SystemC code generation.
Structures and enumerations are not supported as inputs and outputs at the top-level DUT ports for SystemC code generation.