Download Carrol Touch Modular Flat Panel Specifications
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Chapter 5 - Smart-Frame Protocol II CARROLL TOUCH follows the header, read the number of bytes specified by the byte count (the report packet), and verify that the following byte is a trailer byte. If the segment of the incoming byte stream under consideration fits this format, the segment is deemed to be a valid SFP-II report packet and the command error status, report number, and parameters are forwarded to the interpretation layer. Interpretation Layer The format for SFP-II reports at the interpretation layer is as follows: commanderrorstatus reportnumber optionalreportparameters To interpret the report, the host should first examine the command error status parameter. If the command error status parameter indicates an error, the host should take the appropriate action. The host should then examine the report number. If the report number does not correspond to a defined SFP-II report, the host should deem the report invalid. Finally, the host should examine the report to determine that the appropriate number of parameter bytes for the report is present. If the appropriate number is not present, or one or more of the parameter bytes are otherwise invalid for the report (parameter is out of range and so forth), the host should deem the report invalid. If the host determines that all information in the interpretation layer is valid, the host should process the command. The bytes within the report packet are indexed beginning at 0 for the SFP-II report number, and ending at (report packet byte count - 1) for the last parameter byte. The length of the report packet is given by the packet byte count that was read during the validation layer. Example An example of a report issued in response to a valid SFP-II command, GetProtocolVersion (command 65), is: E0 04 00 65 02 12 FF E0 and FF are the header and footer, respectively. 04 indicates the report contains four bytes. 00 is the command error status (Cmderr) and indicates the report is valid. 65 is the report number, which is the 5-10 Touch System Programmer’s Guide