Instruction manual

6 - 3
4. Communication format
The communication formats of the commands and responses between IV-S51M and a personal
computer are outlined below.
Command
: Station No. *****••••••• * * SC SC CR
(H) (L)
Header
(1)
Processing code (2)
Text (2) Checksum code (4)
Terminator
Response
: Station No. ****RC RC RC RC * •••••• * * SC SC CR
H
••• ••• (L ) (H) (L)
Header (1)
Termination code(3)
Text (2)
Processing code (2)
Terminator
Checksum code (4)
(1) Station No.: 00 to 7F(H)
(2) Processing code and text
• They depend on the contents of processing
• On abnormal termination, no text is provided.
(3) Termination code
• The termination code is a 4-digit hexadecimal number.
• When an output is sent through the general purpose serial I/F, 0000(H) is sent on normal
termination.
• On abnormal termination, a code is more than 0001 (H). (The errors are described in the
separate page.)
(4) Checksum code (SC(H), SC(L))
• To improve the reliability of the transmitted data, in addition to a parity check, error detection by
checksum is used for error detection.