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Checksum Instructions

Hardware Method:	Setup eC instruction tags correct checksum to end of the N02 response message. Transmit instructions >00eC08CR. Now any instruction can be assembled in the usual manner, but enter 00 for checksum. The unit returns a N02 response message, plus the correct checksum.
Wildcard:	If ?? is added to the instruction instead of a checksum, the instruction is executed. It sends a "don't care" value for thechecksum. This method is not recommended for programming, because it does not ensure proper communication error checking.
Circulation Method:	Checksum can also be obtained by adding all decimal values of ASCII characters that make up an instruction or response (exclude > for instructions and A for responses). Repeatedly subtract 256 from this sum until the remainder is less than 256. The checksum is 2 digit hex equivalent of the remainder.
Example:	Instruction >80L0800[ ]CR Response A1CAC[ ]CR Instruction Character ASCII Value 8 0 L 0 8 0 0 56 48 76 48 56 48 48 380 380D - 256D = 124D = 7CH The checksum is 7CH and the complete instruction is: >80L08007CCR The response is: Character ASCII 1 C A C 49 67 65 67 248D = F8H The checksum is F8H and the complete response is: A1CACF8CR Note: The ASCII values can be obtained from Appendix H; Decimal/Hexadecimal/ASCII Printable Table

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