iOS Bluetooth retrievePeripherals causes EXC_BAD_ACCESS crash

iOS Bluetooth retrievePeripherals causes EXC_BAD_ACCESS crash

I need to periodically reconnect to a peripheral. First, my central scans
for its UUID, then it connects, then it stores the peripheral.UUID into a
CFUUIDRef variable, and then disconnects. Next, to re-connect it retrieves
the UUID from variable, then either crashes with "EXC_BAD_ACCESS" when it
does retreivePeripherals, or a little later when it does the subsequent
didRetrievePeripherals.
Maybe I'm not storing the UUID correctly, but I don't see the bug. Thanks.
Here's the code..........
-(void)centralManager:(CBCentralManager *)central
didConnectPeripheral:(CBPeripheral *)peripheral
{
/////////////////////// C E N T R A L C O N N E C T E D P E R I
P H E R A L //////////////////////
[self.centralManager stopScan];
// Make sure we get the discovery callbacks
peripheral.delegate = pwr_tx_management;
switch( PWR_TX_manager.present_operation )
{
case POLLING_FOR_GENERIC_DVINEWAVE_DEVICE:
if( dbg_ev ) printf("1");
// Add new record for connection device to local system status
database:
update_device_record( &packed_ad_record ); //
==> device_record_index
// Store peripheral UUID for later, perioed re-connection for
polling:
area_device_status[ device_area ][ device_record_index
].peripheral_UUID = peripheral.UUID;
// uses declaration: CFUUIDRef
peripheral_UUID;
// Disconnect: !!!
[self.centralManager cancelPeripheralConnection: peripheral];
break;
case OPERATION_SPECIFIC_POLLING:
NSLog( @"(7) didConnectPeripheral
" );
if( dbg_ev ) printf("2");
// Proceed with reading device's status and updating local
database:
[peripheral discoverServices:nil]; // request
service, characteristics, then request device send its
packed status record
break;
default:
break;
}
}
// Connects to device specificed by index next_dbase_record .
void connect_specific_device( void )
{
NSLog( @"(5)
connect_specific_device
-
next_dbase_record
= %d",
next_dbase_record
);
CFUUIDRef uuid = area_device_status[ device_area ][ next_dbase_record
].peripheral_UUID;
if( uuid )
{
// Request call to didRetrievePeripherals() with CBPeripheral:
[pwr_tx_management.centralManager retrievePeripherals:[NSArray
arrayWithObject: (id)CFBridgingRelease(uuid)]];
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< crashes here with: Thread
1: EXC_BAD_ACCESS
}
else
{
NSLog( @" - missing area_device_status[][].peripheral_UUID ");
}
}
// Iniates connection to peripheral device specified before by
retrievePeripherals.
- (void) centralManager:(CBCentralManager *)central
didRetrievePeripherals:(CBPeripheral *)peripheral
{
NSLog( @"(6) didRetrievePeripherals");
[central connectPeripheral:peripheral options:nil];
}