ICP DAS USA M-7065 User Manual page 27

A host watchdog timeout has occurred, the
digital output channel s are set to safe value,
and the digital output value that was sent is
ignored.
There will be no response if the command syntax is
incorrect, there is a communication error, or there is
no module with the specified address.
Examples:
Command:#010006
Response:>
Sets DO0、DO3 to off，DO1、DO2 to on, and
the module returns a valid response.
Command:#010016
Response:>
Sets DO0、DO3 to off，DO1、DO2 to on
DO6、DO7、DO8 to off，DO5 to on
Command:#010005
Response:!
Host Watchdog Timeout.
M-7065 User's Manual Ver2.0, Dec. /200 8 ---27