Modbus ASCII, RTU and TCP are all the same type of codes. They only differ in the representation of the data. Our PLC support the same functions: 01, 02, 03, 04,05, 06, 16 in all 3 types of Modbus protocols.
[Moderator's note]: We have moved your post from Frequently Asked Questions board to here as the former was meant to be posted by the moderator only.