Part 4 - C Mechatronics Applications

Abstract

PICDEM Mechatronics includes mechatronics board hardware, mechatronics board connections, and mechatronics board motor drives. The PICDEM mechatronics demonstration board, supplied by Microchip® Inc., is a very useful target system for C control applications. A user manual contains the schematics and general guidance on using the board. It can be programmed using the ICD2 In-Circuit Debugger module, which allows a final stage of fault finding when testing an application in the target hardware. Alternatively, the low-cost PicKit2 programmer can be used. Since our applications here have been tested in simulation mode, the full ICD debugging interface is not needed. A mechatronics board is built around a PIC 16F917, which is similar to the 16F877A but incorporates an LCD driver module, which allows a plain 3.5-digit display to be operated with no additional interfacing. The main output devices are a small DC motor and a stepper motor. An initial test program for the PICDEM board is used to check that the downloading and in-circuit debugging modes are operational. The parallel LCD is operated by specific combinations of inputs that enable the segments as required. The main advantage of the stepper motor is that it provides position control without the feedback required by a DC motor. The mechatronics board is fitted with a light and temperature sensor, each of which produces an analog output in the range of 0–5 V. The PICDEM mechatronics board will now be used as the hardware platform for a temperature controller.