Double Precision words for ModBus


Thread Starter

Punnoose Jacob

I have a typical application to read data from SMITH accuload batch controller using modbus RTU communication module of GE Fanuc PLC. The
volume, mass etc is stored in a 64 bit register ( Double precision word). Since GE Fanuc 90-30 PLCs support only 32 bit long registers could anyone
help me on how to dircetly/indirectly read the 64 bit registers from the batch controller.
Thanks in advance

kalpak dabir

modbus itself does not specify data size except as 8 bit transmission and each register(location) is 16 bit. So, irrespective of the native data size/format the communication can take place. Your problem will be how to use the data once
it is received. That can be solved by taking similar approach that is taken for example when 16 bit data is handled by an 8 bit processor, byte by byte.
kalpak dabir