Using a HP VEE Program to Control your Instrument through Modbus RTU protocol
HP VEE is a very powerful and convenient graphical programming software to control instruments, more and more devices use the Modbus RTU protocol for Serial Communications. This is why ESS, Inc. has developed HP VEE programs to use with its temperature controllers for chart-recording, PID setting and setup. Thanks to its experience, ESS, Inc. now offers a Data Acquisition HP VEE Panel to work with any Modbus RTU instrument.
Download the HP VEE Modbus Package
- This package contains:
Three HP VEE programs, modbus_reader.vee, modbus_writer.vee and an example of utilization Panel_Modbus.vee.
Among these vee files, you could find three HP VEE UserObjects, which are a reading and two writing routines (write positive and negative values). As they require Modbus registers in the decimal format and they return read values in decimal format too, you can insert these routines in your programs to communicate with your Modbus device. The routines take care of splitting the register or value in a high byte and low byte if necessary (for high or negative numbers).