LG Electronics 120S - page 217

Chapter 8 Communication Functions
8-27
(4) Response Format ( NAK response)
Format name Header Station No. Command Command type Error code
(Hex 2 Byte) Tail Frame check
Frame (Example) NAK H0A R(r) ST H1132 ETX BCC
ASCII value 15 3041 5272 5354 31313332 03
* When command is one of lower case(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.
* 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 the status of MASTER-K120S Main unit of station No. 1 is read.
① Computer request Format (PC → MASTER-K120S Main Unit)
Format name Header Station No. Command Command type Tail Frame check
Frame (Example) ENQ H01 R(r) ST EOT BCC
ASCII value H05 H3031 H52(72) H5354 H04
② For ACK response after execution of command (PC ← MASTER-K120S Main Unit)
Format name Header Station No. Command Command type Status data Tail Frame check
Frame (Example) ACK H01 R(r) ST See status data
Format ETX BCC
ASCII value H06 H3031 H52(72) H5354 H03
③ For NAK response after execution of command (PC ← MASTER-K120S Main Unit)
Format name Header Station No. Command Command type Error code Tail Frame check
Frame (Example) NAK H01 R(r) ST Error code (2) ETX BCC
ASCII value H15 H3031 H52(72) H5354 Error code (4) H03