FPGA-based climate controller design for plant tissue culture room

A single-chip FPGA-based embedded processor is presented. The controller controls climatic conditions including managing energy utilization in a plant tissue culture room. The chip has been designed to control four climatic parameters, i.e., temperature, relative humidity, irradiance and photoperiod, to promote plant growth and development. The climate controller is consisted of a processor core and subsystems, which are dedicated hardware components, i.e., I/O interface, climate unit, timing generator and user interface. The processor core is an 8-bit CISC microprocessor executing 30 instructions. Subsystems run specific functions to reduce processing loads and to simultaneously execute the operations. The processor core sends commands directly to instruct the subsystems. Exchanging data among the subsystems is accomplished through a shared-memory interprocess communication. The hardware/software codesign method is adapted for FPGA-based design. VHDL code has been used as a design entry. The designed chip is utilized 645 CLB slices and 88 IOs of a Xilinx Spartan-II XC2S50 FPGA.