HL7812 issue with data transfer via http post

IoT Modules HL78
21

I’ve testet with the original Sierra Wireless HL78 dev kit.

22

I tried changing the baud rate but I get the following error:
AT+IPR?
+CME ERROR: 4
AT+IPR=?
+CME ERROR: 4
AT+IPR=38400
+CME ERROR: 4

What could be wrong?

23

i don’t see problem:

ati3
HL7812.5.4.10.0

OK
at+ipr?
+IPR: 115200

OK
at+ipr=?
+IPR: (1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600, 3000000)

OK
24

Strange - here is my log:

grafik

25

are you using UART0?

26

I’m using the HL78 dev kit and have connected it to “MAIN USB”.
I see 4 serial communication ports in Device Manager:
grafik

Probably AT, AT/PPP, NMEA and MSE (Modem to USE).

AT commands are possible via COM7 and COM12 (probably AT and AT/PPP).

grafik

COM12:
grafik

COM7:
grafik

27

can you try with the UART1 port?

28

Are you using uart or usb?

29

Ok, I switched to UART1 and everything works fine now (without changing the baud rate).
How can this be explained?
Does http post not work over USB?

grafik
grafik569×829 19.6 KB

30

Does problem only happen in windows?
Did you try linux?

31

So far I have only tested on Windows (10).
Today I don’t have a chance to test it with a Linux system (maybe in the next few days).

32

Thanks all for your help and support. I now did fixed the problem:

Although all AT commands work fine, if closed with CR only, the header information must be closed by CR_LF

Now everything work as expected.

  //--- add http header ---
  sprintf( Usart3_TxBuffer, "Accept: text/plain\r\n" );
  SendCmdToGsmModul( Usart3_TxBuffer );
  sprintf( Usart3_TxBuffer, "Content-Type: application/x-www-form-urlencoded\r\n" );
  SendCmdToGsmModul( Usart3_TxBuffer );
  sprintf( Usart3_TxBuffer, "Content-Length: %d\r\n", BytesToSent );
  SendCmdToGsmModul( Usart3_TxBuffer );
  strcpy( Usart3_TxBuffer, "--EOF--Pattern--" ); 
  SendDataToGsmModul( Usart3_TxBuffer, 16 );
  AnswerReceived = WaitForModemAnswerOk( RX_ACK_TIME );