CC2541: How to send the string command with CC2541 via bluetooth

When I tried to send this command(1,0,0,0,0,0,0,0,0). In print I got 508

I suppose you can use GATT_WriteCharValue to write to a specific GATT characteristics to send a string.

okay. Let me test this one!

any sample code on this. How to use this command and on which file do I need to use it. 

Hi YiKai Chen and Ammar N,

static void simpleProfileChangeCB( uint16 paramID)
{
    char Data[11];
    switch( paramID )

{
    case SIMPLEPROFILE_CHAR1:
    attWriteReq_t wrreq; 

   wrreq.pValue= Data;
   wrreq.sig = 0;
   wrreq.cmd = 0;
   GATT_WriteCharValue(paramID, &wrreq, SIMPLEPROFILE_CHAR1);
   printf("COMMAND: %s'\n'",Data);

}

}

This will work ?? 

I want to send (1,0,0,0,0,0,0,0,0) as string 

Regards,

Yatin Baluja 

I suppose you have GATT service/characteristic implemented on BLE peripheral so you should use GATT_WriteCharValue on BLE central to write characteristic to BLE peripheral.

I am only using BLEperipheral....I know App will send the string to the BLEPeripheral. It is possible to set GATT service in BLEPeripheral like simpleProfileChangeCB ?? I want to send the string from the App and BLEPeripheral will receive it and perform the operation but I don't know how to set the GATT service like simpleProfile so that I can receive the string command on CC2541

One more thing, it is possible to set the time in milliseconds in CC2541? If yes, how ?

ok

Hi YiKai Chen, 

I changed the length of the CHAR1 to 20 bytes and I send the command from the nrfConnect App and printed the command. I am attaching the screenshot what I'm getting after sending (1,0,0,0,0,0,0,0).

I'm also attaching the  simpleProfile_WriteAttrCB code.

/*********************************************************************
* @fn simpleProfile_WriteAttrCB
*
* @brief Validate attribute data prior to a write operation
*
* @param connHandle - connection message was received on
* @param pAttr - pointer to attribute
* @param pValue - pointer to data to be written
* @param len - length of data
* @param offset - offset of the first octet to be written
* @param method - type of write message
*
* @return SUCCESS, blePending or Failure
*/
static bStatus_t simpleProfile_WriteAttrCB( uint16 connHandle, gattAttribute_t *pAttr,
uint8 *pValue, uint8 len, uint16 offset,
uint8 method )
{
bStatus_t status = SUCCESS;
uint8 notifyApp = 0xEE ;

// If attribute permissions require authorization to write, return error
if ( gattPermitAuthorWrite( pAttr->permissions ) )
{
// Insufficient authorization
return ( ATT_ERR_INSUFFICIENT_AUTHOR );
}

if ( pAttr->type.len == ATT_BT_UUID_SIZE )
{
// 16-bit UUID
uint16 uuid = BUILD_UINT16( pAttr->type.uuid[0], pAttr->type.uuid[1]);
switch ( uuid )
{
case SIMPLEPROFILE_CHAR1_UUID:
case SIMPLEPROFILE_CHAR3_UUID:
case SIMPLEPROFILE_CHAR4_UUID:
case SIMPLEPROFILE_CHAR5_UUID:

/*
//Validate the value
// Make sure it's not a blob oper
if ( offset == 0 )
{
if ( len != 1 )
{
status = ATT_ERR_INVALID_VALUE_SIZE;
}
}
else
{
status = ATT_ERR_ATTR_NOT_LONG;
}
*/
//Write the value
if ( status == SUCCESS )
{
uint8 *pCurValue = (uint8 *)pAttr->pValue;
/**pCurValue = pValue[0];
*pCurValue++;
*pCurValue = pValue[1];*/
memcpy(pCurValue,pValue,len);
bledatalen = len;

if( pAttr->pValue == &simpleProfileChar1 )
{
notifyApp = SIMPLEPROFILE_CHAR1;
}
if( pAttr->pValue == &simpleProfileChar3 )
{
notifyApp = SIMPLEPROFILE_CHAR3;
}
if( pAttr->pValue == &simpleProfileChar4 )
{
notifyApp = SIMPLEPROFILE_CHAR4;
}

if( pAttr->pValue == &simpleProfileChar5 )
{
notifyApp = SIMPLEPROFILE_CHAR5;
}
}

break;

case GATT_CLIENT_CHAR_CFG_UUID:
status = GATTServApp_ProcessCCCWriteReq( connHandle, pAttr, pValue, len,
offset, GATT_CLIENT_CFG_NOTIFY );
break;

default:
// Should never get here! (characteristics 2 and 4 do not have write permissions)
status = ATT_ERR_ATTR_NOT_FOUND;
break;
}
}
else
{
// 128-bit UUID
status = ATT_ERR_INVALID_HANDLE;
}

// If a charactersitic value changed then callback function to notify application of change
if ( (notifyApp != 0xEE) && simpleProfile_AppCBs && simpleProfile_AppCBs->pfnSimpleProfileChange )
{
simpleProfile_AppCBs->pfnSimpleProfileChange( notifyApp );
}

return ( status );
}

Regards,

Yatin Baluja 

Do you check if your simpleProfile_WriteAttrCB is triggered and if yes, what value is written over the air?

Hi YiKai Chen,

If I'm sending only "1" command then simpleProfile_WriteAttrCB is triggering and providing me output as I'm using serial print to print the values but if I'm sending the command as string like 100000 then it is not printing anything.  

What do you mean "sending the command as string like 100000"? What is the data type of your written characteristic?

Hi YiKai Chen,

/*********************************************************************
* @fn simpleProfileChangeCB
*
* @brief Callback from SimpleBLEProfile indicating a value changesimpleProfileChangeCB
*
* @param paramID - parameter ID of the value that was changed.
*
* @return none
*/
static void simpleProfileChangeCB( uint16 paramID )
{
  uint8 newValue[15];
  switch( paramID )
{
  case SIMPLEPROFILE_CHAR1:
  SimpleProfile_GetParameter( SIMPLEPROFILE_CHAR1, &newValue );
  printf("Command: %x\n",newValue);
break;

}

}

This is the code I'm testing and from the App I am testing sending "TEXT".

So, for example if I'm sending "1" from nrfConnect APP to Characteristics 1, In the serial print output is printing as 1fb but when I'm sending string like 110000000 it is not printing anything. So, basically 110000000 are the status of the LED's for example 11 means LED1 and LED2 are ON and others are OFF. But this data will be send directly by the App and the firmware will pass this status to CC2541 using Bluetooth. 

Regards,

Yatin Baluja 

I am not familiar with nrfConnect APP, you might need to use sniffer to check what nrfConnect APP actually send out over the air when you said you send "1" from nrfConnect APP to Characteristics 1.

Hi YiKai Chen,

How to send 20 bytes data with CC2541 on one Bluetooth UUID? Do I need array or string ? but how I can do using SimpleBLEPeripheral example.

Regards,

Yatin Baluja

I suppose you can use an array and GATT_Notification to send the 20 bytes.

This will work with the BLEPeripheral like on the server side ? I am not using BLECentral which is basically client

Basically, BLE peripheral need to have a GATT service to send notification.