Chapter 8 Serial Communication Module AH10SCM 8.6.4 Modbus Advance Please refer to the introduction in section 8.5 for more information. 8.6.5 COM Port History During communication, all packets are recorded in a buffer zone in AH10SCM-5A. The COM port history helps users debug a program. Packets which are sent/received are recorded in this buffer zone. The capacity of the buffer zone is 2048 bytes. Only the latest communication data is recorded. The older communication data is discarded. Besides, the buffer zone is a non-latched area. Data in the buffer zone will disappear if there is a power failure. The COM port history function can be enabled and disabled.
The data in the buffer zone can also be uploaded to SCMSoft. After users right-click COM PORT History , they can select Start COM PORT History , Stop COM PORT History , or Upload COM PORT History Data . If Start COM PORT History is selected, all communication through COM1 and COM2 will be recorded. If Stop COM PORT History is selected, the recording of all communication through COM1 and COM2 will stop. If Upload COM PORT History Data is selected, all communication data in AH10SCM-5A will be uploaded to SCMSoft. Please notice that the recording of all communication data stops before the data is uploaded to SCMSoft.
If users want resume the recording of communication data, they must enable the COM port history function again. 8-33