6 replies to this topic

[Fahdil]

Hi Guys

 

lately I'm try to send SMS via GSMshield (using UART port Com1), but I dont know why it always return error as result (the SMS never sent). Can anybody help me to find the way out...

Public Class GSM_UART_serial        Private Shared GSM_UART As SerialPort        Private Shared Respons As String        Private Shared bytesTosend As Byte()        Private Shared SendingSMS As Boolean        Public Shared Sub Main()            OnboardLed = New OutputPort(Pins.ONBOARD_LED, False)            D9 = New OutputPort(Pins.GPIO_PIN_D9, False)            SendingSMS = False            D9.Write(True)            Thread.Sleep(500)            D9.Write(False)            GSM_UART = New SerialPort("COM1", 9600, Parity.None, 8, StopBits.One)            AddHandler GSM_UART.DataReceived, New SerialDataReceivedEventHandler(AddressOf RecieveData)            If GSM_UART.IsOpen = False Then                GSM_UART.Open()                Debug.Print("Port Opening" & " : at baudRate= " & GSM_UART.BaudRate)            Else                Debug.Print("Port is ready...")            End If            SendingSMS = True            While SendingSMS = True                Thread.Sleep(250)                GSM_UART_dataWrite("AT+CMGF=1" & vbCr)                Thread.Sleep(250)                GSM_UART_dataWrite("ATE" & vbCr)                Thread.Sleep(250)                GSM_UART_dataWrite("AT+CMGS=")                Thread.Sleep(250)                GSM_UART.WriteByte(34)                GSM_UART_dataWrite("085218877358")                GSM_UART.WriteByte(34)                GSM_UART_dataWrite("" & vbCr)                Thread.Sleep(250)                GSM_UART_dataWrite("Body Massage being so good" & vbCr)                Thread.Sleep(250)                GSM_UART_dataWrite("x1A" & vbCr)                Thread.Sleep(1000)                SendingSMS = False            End While            Debug.Print(Respons & "?")            Thread.Sleep(Timeout.Infinite)        End Sub                Private Shared Sub GSM_UART_dataWrite(ByVal Command As String)            bytesTosend = Encoding.UTF8.GetBytes(Command)            Debug.Print("Send port : " & Command)            GSM_UART.Write(bytesTosend, 0, bytesTosend.Length)            Debug.Print("Port is writing...")        End Sub	    Private Shared Sub RecieveData(ByVal sender As Object, ByVal e As SerialDataReceivedEventArgs)		    Dim Length As Integer = GSM_UART.BytesToRead		    Dim bufferData As Byte() = New Byte(Length - 1) {}		    GSM_UART.Read(bufferData, 0, Length)		    Respons += New String(Encoding.UTF8.GetChars(bufferData))		    If Respons.IndexOf(vbLf) >= 0 Then			    Respons = Respons.Trim()			    If Respons <> "" Then				    OnboardLed.Write(state:=True)				    Debug.Print(Respons)			    End If			    Respons = ""			    If Respons = "" Then				    OnboardLed.Write(state:=False)				    Debug.Print(Respons)			    End If		    End If	    End Subend class

very appreciate for your help

 

Best Regards

[Fahdil]

I little bit better... but still error..... after I modified the code like this, it's going better, the error comes after Ctrl-z. so I think, I need to know how to send Ctrl-Z  (0x1A)... I try to use GSM_UART.writebyte(0x1A) it doesnt work either.

 While SendingSMS = True                Thread.Sleep(250)                GSM_UART_dataWrite("AT+CMGS=")                Thread.Sleep(250)                GSM_UART.WriteByte(34)                GSM_UART_dataWrite("085218877358")                GSM_UART.WriteByte(34)                GSM_UART_dataWrite("" & vbLf)                Thread.Sleep(500)                GSM_UART_dataWrite("Body Massage being so good")                Thread.Sleep(250)                GSM_UART_dataWrite("0x1A" & vbCr)                Thread.Sleep(1000)                                SendingSMS = False            End While

[JoopC]

Your problem is the syntax of converting hex 0x1A is in Visual Basic &H1A   0x = &H

[Nighthawk]

Please note that after powering on the SIM900 (using pin D9), you need to WAIT till you get a "CALL READY" message before using any commands that use the SIM card. It is written in the IComSat manual.

 

This usually happens around 7-10 seconds after powering up the SIM900.

[Nighthawk]

Also, I'm not 100% sure about this, but I believe you need to send Carriage Return AND Line Feed (vbCrLf) over the serial connection. 

[Fahdil]

it's done... and I adopt this class....

 

thx to forum

 

*edit

note for Icomsat v1.1:

 

you have to set up the serial :

baudrate : 9600 (up to 57000 see sim900 datasheet for details)

parity : none (seedstudio GSM sheild using parity.odd) 

dataBits = 8

stopBits = One

 

for Netduino Compatibility :

 

you have to set Pin D8 to Low. I dont know why but if it's still on High, powering the GSM shield via pin 9 (send High fo 500ms) wont work.

 

cheers

Attached Files

•  GSM_UART.cs   10.96KB   4 downloads

[Fahdil]

next to try:

 

How to use IcomSat v1.1 as fax modem...