VSI VisSim/ECD Generates Efficient Fixed Point C Code For A Range Of Targets

After simulation, VisSim’s Code Generator uses the same diagram to generate highly efficient C code and compiles to an executable image for an embedded target. The VisSim target HotLink downloads the executable image and lets you change controller gains from the PC host and displays digital scope results of on-target signals.

VisSim/ECD is unique in its ability to generate highly efficient, high sample rate, low jitter target executables. For example, a closed-loop PID control with encoder input and PWM output and one digital output line takes 1.1K flash and 100 bytes RAM on the MSP430, and VisSim/ECD generated code can sample at rates over 1 MHz on the F28335. As a TI third party partner, Visual Solutions has gained valuable access to TI technology to tune VisSim/ECD to make best use of TI processors and peripherals.

Kevin Godfrey, Principal Engineer, AMETEK Airtechnology Group Limited, said: VisSim/ECD has been instrumental in letting us get our controller working well and hitting our design goals and deadlines. The quality of the code generator has removed the need for an independent coding staff, which has lowered our costs and sped up overall implementation. The VisSim folks have been very helpful and responsive when we have any questions or issues.

Features:

•VisSim/Fixed Point block set performs simulation and efficient code generation of scaled fixed-point operations like sin, cos, sqrt, atan2, FIR and IIR; overflow and precision loss effects are easily seen and corrected at simulation time; auto-scaling speeds fixed-point development; in-line code generation creates fast target code.

•Peripheral blocks to generate code for C2000 on-chip devices: 280x ePWM, eQEP, eCAP, ADC, GPIO, quadrature encoder, event capture, CAN 2.0, SCI(RS232,UART,serial port), SPI, McBSP, watchdog and interrupts.

•Full control of PWM including dynamic control of PWM period and phase, ADC start of conversion, trip zone, deadband intervals, action selection.

•Interrupt-based queue drivers for serial, SPI and McBSP; user selectable queue lengths and use of hardware FIFO result in lower system overhead.

•Diagram-based interrupt handlers for XINT, ADC, PWM and DMA.

•Easy creation of background tasks Subsystem dialogue box to create a background task that runs at a user specified rate.

•TI C2000 Digital Motor Control block set supports simulation and code generation of efficient, fixed-point routines for Park and Clarke transforms, rotor speed and flux estimation, PID control, space vector wave form generation for AC Induction and brushless DC motor control.

•Automatic C code generation of production quality fixed-point code, compile, link and JTAG download.

•Supported processors include TI MSP430 (all flavours), C2000 (all flavours) including F2808 and variations, F28027, F28035 (Piccolo), F28335(Delfino), LF2407, F2812, C5510, C6713, Intel x86 PC.

•Retention of the VisSim GUI while algorithm executes on MCU lets you visualise interactive plots of MCU outputs and change MCU gains and parameters in real time.

•VisSim Code Composer Studio plug-in for automatic CCS project creation.

•TI C2000 CAN bus support.

•Serial-port-based LCD display support.

•Efficient 7- and 14-segment LCD display support for MSP430; user table can customise segment assignments; auto conversion from scaled fixed-point to decimal display uses no floating point and no divide for maximum efficiency on MSP architecture.

•Conditional execution of subsystems based on any Boolean condition, including occurrence of interrupt.

•User control of execution order of parallel flows is done top down; subsystem contents are completely executed before the next block on given layer, which provides fine grain control necessary for hardware device access.

•State transition block provides unlimited states and transition conditions, transition conditions are C expressions.

The VisSim product range is supplied and supported by Adept Scientific in the UK, Ireland, Germany, Austria, Scandinavia and the Nordic countries.