Hi,
I've been reading some devices with mango via modbus IP over satellite. Apart from the high latency we also have a bandwidth limit and ridiculous charges for data used beyond our limit.
I've noticed that if the addresses being read are contiguous they get read all at once with the 'read multiple registers' modbus command whereas if they are not strictly contiguous a seperate read request is issued for each register or group of contiguous registers.
Each read register request is about 50 bytes regardless of how many registers are read. Likewise there is an overhead of about 50 bytes per reply, regardless of how many registers are in the reply.
It takes mango 3 seconds per request-response cycle with these satellites. Cutting down the number of requests is going to allow us to increase the refresh rate and save on bandwidth charges on the satellite.
Temporarily I could add points to make the addresses contiguous but then I have all the unused points cluttering & confusing the instance.
Is the source for the com.serotonin.modbus4j package available so I could take a crack at getting the number of modbus requests we're making down?
Cheers
Craig