Modbus uses diagnostic counters to enable performance and error management. Read the counter of incorrect bus messages due to overrun errors Read the counter of messages sent to the slave but not answered because of the Slave Device Busy exception code 06 Read the counter of messages sent to the slave but not answered because of the Negative Acknowledge exception code 07 Return slave negative acknowledge counter Read the counter of messages sent to the slave Read the counter of exception responses managed by the slave Read the counter of incorrect bus messages managed by the slave Read the counter of correct bus messages managed by the slave The scattered holding register read function is available:
Recommended period is at least every 15 minutes. It is therefore mandatory to set date and time for all Modbus slaves after recovering the 24 Vdc power supply.įurthermore, due to the clock drift of each Modbus slave, it is mandatory to set date and time for all Modbus slaves periodically. In case of 24 Vdc power loss, the date and time of the Modbus slaves without battery is not refreshed anymore. If the date-time structure content is not consistent with a true date-time (that is, an invalid date-time), the value returned in the Date-Time field is set to 0 by the device. The normal response is an echo of the request, returned after the date-time has been updated in the remote device.
