Ben Krasnow developed this dispensing system that can measure out a desired mass of material via a dispensing valve controlled by a Parallax Propeller. He already had an American Weigh Scales miniPro-100, and decided to hack it so that the Propeller can discover how much mass is on the balance and regulate the dispensing valve appropriately. “The balance contains a Cirrus CS5530 24-bit ADC. I tapped the clock and data lines and found bursts of data that occurred at 7.5Hz. The clock is about 150KHz. I used a Parallax Propeller running assembly in one of its cores to capture the data stream and load it into my main program.”
This video concentrates on the scale/Propeller connection, and Ben plans to detail the dispensing mechanism control in a later video.