Chapter 6 Applied Instructions or one word. 7. The MODRW instruction is not executed if the sending flags SM96 and SM97 are not ON. 8. If a communication timeout occurs, the timeout flags SM104 and SM105 are ON, and the receiving flags SM98 and SM99 are OFF. 9. If an error occurs while receiving data, the error flags SM102 and SM103 are ON, and the receiving flags SM98 and SM99 are OFF. 10. If the function code specified by S 2 is related to word devices, the device in the external equipment with which the PLC communicates must be a word device.
If the function code specified by S 2 is related to bit devices, the device in the external equipment with which the PLC communicates must be a bit device. 11. Please refer to section 6.19.3 for more details on communication register setups (SM, SR). 6_ 6-547