I am interested in seeing a few of Trinamics products, like the TMC246, TMC423, and TMC428 ics. These are very easy to add to a circuit and in bulk they are relatively cheap. The TMC428 is the central chip of the chipset. It has a SPI bus connection between the uP and the TMC423. The uP sends target position and velocity parameters to the TMC428 and it calculates ramp up/duration/ramp down values and sends them to the TMC246 chips which are the actual motor drivers. The connection between the TMC428 and the (one to three) TMC246 is a seperate SPI bus. The TMC423 is the encoder and reference switch controller that sends its values to the TMC428 to help with position and velocity calculations. All of the hard work of 3-axis stepper motor controllers are converted into simple commands, and lets the uP tend to other work. The URL of the site is www.trinamicusa.com .
Peter Norberg Consulting StepperBoard Products combine the serial port command input (via RS232, USB or microcontroller) with position and acceleration calculation and much more one one pcb. Voltage or current regulated models, 2 or 4 axis, CNC.