A controller's direct SMS reply can return a Boolean value as 0 or 1, but the available evidence does not support replacing those values with custom text in that reply. To return readable states such as NORMAL and ALARM, process the received command and select a predefined outgoing SMS according to the Boolean state.
Direct Boolean Reply Limitation
When an SMS management function replies with a variable value, it can change the numeric value but not substitute arbitrary text for that value. Therefore, a request such as SOST cannot directly format Boolean 0 as NORMAL and Boolean 1 as ALARM through value substitution alone.
| Method | Boolean result | Custom state text |
|---|---|---|
| Direct variable reply |
0 or 1
|
Not supported |
| Conditional SMS selection | Selects a message by state | Supported through predefined messages |
Configure Conditional SMS Selection
Use the received SMS as a command trigger rather than relying on the direct variable reply. The controller evaluates the alarm Boolean and selects one of two predefined responses.
- Configure the controller to recognize the incoming command
SOST. - After receiving the command, evaluate the required Boolean alarm variable.
- If the value is
0, select the predefinedNORMALmessage. - If the value is
1, select the predefinedALARMmessage. - Send the selected SMS to the requesting recipient.
Message Count and Scaling
The described selection method supports as many as 255 outgoing SMS variants. However, each required readable response must be configured and selected explicitly. If one query must report many equipment or alarm states, the number of message variants and conditional branches can become difficult to maintain; the evidence does not identify a supported mechanism for inserting custom words directly into a variable-based reply.
Verification
Test both Boolean states independently. Set or simulate the alarm state as 0, send SOST, and confirm receipt of NORMAL; then set or simulate it as 1, repeat the request, and confirm receipt of ALARM. Also verify that the direct variable-reply path still returns only its numeric representation and is not being mistaken for the conditional message path.
FAQ
Can a controller SMS reply show words instead of 0 or 1?
Not through the direct variable-reply method described in the evidence. Use conditional logic to select separate predefined text messages for Boolean 0 and 1.
How do I make SOST return NORMAL or ALARM?
Recognize SOST as an incoming command, evaluate the alarm Boolean, and send NORMAL for 0 or ALARM for 1.
How many SMS response variants can be selected?
The described approach supports up to 255 SMS variants, although every response and its selection condition must be configured.
