streamDevice configuration issues with serial ports

[LONG FENG via Tech-talk <tech-talk at aps.anl.gov>]

Hi all,

     I have a sensor that communicates via RS485 with the Modbus RTU protocol. I want to use streamDevice to read the sensor values, but I've found that there is no data transmission between the system and the sensor, and the following issues have occurred：

epics> 2024/10/28 21:00:05.370941 SI Sensor:Data: No reply within 10000 ms to "<01><04><00><00><00><06>p<08><0d><0a>"
2024/10/28 21:00:20.484243 SI Sensor:Data: No reply within 10000 ms to "<01><04><00><00><00><06>p<08><0d><0a>"
2024/10/28 21:00:35.322913 SI Sensor:Data: No reply within 10000 ms to "<01><04><00><00><00><06>p<08><0d><0a>"
2024/10/28 21:00:50.427348 SI Sensor:Data: No reply within 10000 ms to "<01><04><00><00><00><06>p<08><0d><0a>"

    My protocol(RS485Test.proto) file is written like this：

Terminator = CR LF;
InTerminator = CR LF;
ReplyTimeout = 10000;
ReadTimeout = 10000;

getData
{
  out "\x01\x04\x00\x00\x00\x06\x70\x08";
  in "%r";
}

    Record(RS485Test.db)：

record(ai, "Sensor:Data")
{
    field(DTYP, "stream")
    field(INP, "@RS485Test.proto getData SI")
    field(SCAN, "5 second")
}

    IOC st.cmd:

#!../../bin/linux-x86_64/dataProcessing
 
< envPaths

dbLoadDatabase("../../dbd/dataProcessing.dbd",0,0)
dataProcessing_registerRecordDeviceDriver pdbbase
epicsEnvSet ("STREAM_PROTOCOL_PATH", "/home/training/examples/dataProcessingApp/Db")


drvAsynSerialPortConfigure("SI", "/dev/ttyS3")
asynSetOption("SI", 0, "baud", "9600")
asynSetOption("SI", 0, "bits", "8")
asynSetOption("SI", 0, "parity", "none")
asynSetOption("SI", 0, "stop", "1")
asynSetOption("SI", 0, "clocal", "Y")
asynSetOption("SI", 0, "crtscts", "N")

## Load record instances
dbLoadRecords("../../db/RS485Test.db")

iocInit()

    Is there anything wrong with these?