Trycom Technology TRP-C29U, Руководство пользователя

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5. Function description
Power on mode: When power fail, system reset or host watchdog timeout will cause the
module reboot then into power on mode, the module’s digital output value will return to the
before setting.
And module can accept the host’s command to change the digital output value.
Dual Watchdog: Module self watchdog: The module’s watchdog is a hardware reset circuit
while working in harsh or noisy environment, the module may be down by the external, The
circuit may let the module to work continues and never halt.
Host watchdog: The host watchdog is software function to monitor the module's output states to
prevent the module from communication problem or system halt due to unexpected situation,
It’s purpose is to prevent the RS485 network from communication problem or host halt. When
the timeout interval expired, the module will turn all output to predefined safe value. This can
prevent the controlled target from unexpected situation.
Safe mode: If the user install the watch-dog enable on the RS485 line, The host will send the
reset module’s watchdog command one by one, when the host is not send the command (May
be is RS485 off line or host halt), the module will watchdog timeout then into the safe mode, if
the module into the safe mode, the digital out will not be changed until the watchdog disable.
6. TRPCOM ASCII Command Protocol Description
Command Format :”Leading Code”+”ID A”C”CHK”+(cr).
Response Format :”Leading Code”+”ID A”Data”+”CHK”+(cr).
7. How to Calculate the Checksum
1. Calculate all characters of the command string to get the ASCII sum, except the character
return.
2. Mask the sum of string with 0FFH.
Example:
Send the command is “$06M”.
Sum of string is “$”+”0”+”6”+”M”=“24H”+”30H”+” 4D“=“A1H”……The checksum and [CHK]=“A1”.
Response string with checksum is:” A1 “.
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