Hi All,
I have a toy drone's TX, which using XN297Lbw RF chip as transmitter. By using logic analyzer with Sigrok , I found this TX config as follows:
- EN_AA (Auto ACK) register as "1"
- TX address: 0x6D, 0x6A, 0x77, 0x77, 0x77
- Bind CH: 0x36
- Payload size: 16
With above information and using arduino + module XN297Lbw, I can communicate with this TX (Bind and receive joystick data)
But when I use NRF24L01 RF chip as RX and xn297_scramble to set for tx,rx address, I can not communicate with TX.
static const uint8_t xn297_scramble[] = {
0xe3, 0xb1, 0x4b, 0xea, 0x85, 0xbc, 0xe5, 0x66,
0x0d, 0xae, 0x8c, 0x88, 0x12, 0x69, 0xee, 0x1f,
0xc7, 0x62, 0x97, 0xd5, 0x0b, 0x79, 0xca, 0xcc
};
static void nrf24_set_xn297_address( uint8_t * addr )
{
uint8_t rxaddr[ 6 ] = { 0x2a };
crc_addr = 0xb5d2;
for ( int i = 5; i > 0; --i ) {
rxaddr[ i ] = addr[ i - 1 ] ^ xn297_scramble[ 5 - i ];
if ( crc_en ) {
crc_addr = CRC16_UPDATE( crc_addr, rxaddr[ i ] );
}
}
// write rx address
rx_writeregs( rxaddr, sizeof( rxaddr ) );
// write tx address
rxaddr[ 0 ] = 0x30;
rx_writeregs( rxaddr, sizeof( rxaddr ) );
}
void rx_init()
{
debugln("rx_init");
drv_rx_init();
#define XN_TO_TX B00000010
#define XN_TO_RX B00000011
#define XN_POWER B00000001 | ( ( TX_POWER & 7 ) << 3 )
rx_writereg( SETUP_AW, 3 ); // address size (5 bytes)
static int rxaddr[ 5 ] = { /*0x2a,*/ 0x6D, 0x6A, 0x77, 0x77, 0x77 };
// static int rxaddr[ 5 ] = { /*0x2a,*/ 0x55, 0x0f, 0x71, 0x77, 0x77 };
//rx_writeregs( rxaddr, sizeof( rxaddr ) );
// rx_writetxaddress(rxaddr);
// rx_writerxaddress(rxaddr);
nrf24_set_xn297_address( (uint8_t*)rxaddr );
rx_writereg( EN_AA, 1 ); // aa enable
rx_writereg( EN_RXADDR, 1 ); // pipe 0 only
rx_writereg( RF_SETUP, XN_POWER ); // power / data rate / lna
rx_writereg( RX_PW_P0, PAYLOAD_SIZE ); // payload size
rx_writereg( SETUP_RETR, 0 ); // no retransmissions (redundant?)
rx_writereg( SETUP_AW, 3 ); // address size (5 bytes)
rx_command( FLUSH_RX );
rx_writereg( RF_CH, BIND_CH ); // bind on channel 0
debugln("Read RF_CH: 0x%x", rx_readreg(RF_CH));
rx_writereg( 0x1d, B00111000 ); // 64 bit payload, software ce
// static uint8_t cehigh_regs[ 2 ] = { 0xFD, 0 }; // internal CE high command, 0 also required
// rx_writeregs( cehigh_regs, sizeof( cehigh_regs ) );
rx_writereg( 0, XN_TO_RX ); // power up, crc enabled, rx mode
int rxcheck = rx_readreg( 0x0f ); // rx address pipe 5
// should be 0xc6
extern void failloop( int );
if ( rxcheck != 0xc6 ) {
failloop( 3 );
}
}
If I config EN_AA reg as "0" and use address to xn297 preamble " 0x55, 0x0f, 0x71" I can receive bind package, but as I understand , TX use Auto Ack to detect that RX (drone) already received bind package and go to data mode. If EN_AA set to 0, TX will not able to know ack from RX.
I hope someone can help me to found a solution for this.
Thank you for your attention.
