Chorus Motor Controller Firmware

Client: Chorus Motors
Ongoing since August 2001

The firmware for the Chorus Motor controller implements rules for controlling motor speed, rate of change of speed over multiple speed ranges, use of special high-torque capability at low speed, and various other parameters. The firmware operates on an Atmel ATmega128L (second-generation prototype) and a PIC17C756a (first-generation). It is written in C and assembly. The firmware interacts with a Spartan 3 FPGA (programmed by a third party) which implements the innards of the motor controller, as well as a keypad/LCD and/or PC front-end interface.

High reliability: the firmware will eventually be used in large motor systems in electrically noisy environments. Glitches in the firmware's interfaces or crashes in the code could have drastic consequences for the motor and surrounding equipment, so the firmware must be reliable.

Changing requirements: This motor controller system has evolved over a period of time and through many changes in operational requirements. The firmware uses specific rules to translate requests to change speed, reverse, stop, etc. into detailed change sequences for FPGA parameters. It is a good example of how by understanding your system, Pink Shirt can provide good value on your project.

Successful remote consulting: All of the work has been performed from my home, using prototype electronics for testing. Most of the interaction with the client, whose lab is in Boston, is via email and telephone. Frequent communication insures that we understand each other well and they get the software they need from me.