Chapter 8 Communication Functions
8-14
(4) Response format (NAK response)
Format name Header Station No. Command Command type Error code
(Hex 2 Byte) Tail Frame check
Ex. of frame NAK H10 r SB H1132 ETX BCC
ASCII value H15 H3130 H72 H5342 H31313332 H03
Item Explanation
BCC When command is lowercase(r), only one lower byte of the value resulted by adding 1 Byte
each to ASCII values from NAK to ETX is converted into ASCII and added to BCC, and sent.
Error code Hex and 2 bytes(ASCII code, 4 bytes) indicate error type. For the details, see 8.1.8 Error
codes.
(5) Example
This example supposes that 2 WORDs from M000 of station No. 10 is read and BCC value is checked. Also it is supposed
that data in M000 and in M001 is as follow:
M000 = H1234
M001 = H5678
① Computer request format (PC → MASTER-K120S Main Unit)
Format name Header Station No. Command Command
type Device length Device name Number of data Tail Frame check
Frame (Example)
ENQ H0A r SB H06 %MW000 H02 EOT BCC
ASCII value H05 H3041 H72 H5342 H3036 H254D5730
3030 H3032 H04
② For ACK response after execution of command(PC ← MASTER-K120S Main Unit)
Format name Header Station No. Command Command
type
Number of
data Data Tail Frame check
Frame (Example)
ACK H0A r SB H04 12345678 ETX BCC
ASCII value H06 H3041 H72 H5342 H3034 H3132333435363738 03
③ For NAK response after execution of command(PC ← MASTER-K120S Main Unit)
Format name Header Station No> Command Command type Error code
Tail
BCC
Frame (Example)
NAK H0A r SB
Error code
(2Byte) ETX BCC
ASCII value H15 H3041 H72 H5342
Error code
(4Byte) H03