Grouping: Single Values. Normally, ModMaster will try to transfer as many values as possible in each read or write request that it sends to the slave. If you select the Single Values checkbox, then it will transfer only one value in each request.

Error Handling: Continue Polling. Normally, ModMaster will stop polling if it receives an error response from the slave. If you select the Continue Polling, then it will continue polling if it receives an error response.

Pass Delay. The Pass Delay field is used to insert a time delay into the polling sequence to reduce the load on the slave (and maybe also on the computer running ModMaster). The delay is inserted after each complete pass through all the registers. The delay is measured in milliseconds. (Also see Request Delay).