NRF24L01+ IRQ Issue

Hi All,

I am testing the functionality of NRF24L01+ and for my purposes I have configured it as PTX, No Auto ACK.

I am able to communicate with the chip just fine and able to configure all the registers (confirmed with a logic analyzer).

However when I try to send data, the IRQ pin never goes low.

below is the configuration I used for NRF24L01+

_delay_ms(1000); 	//allow radio to stabilize after power on

uint8_t val[5];

val[0]=0x00;		//disable AA(auto acknowledgements)
RADIO_READWRITE(W, EN_AA, val, 1);

val[0]=0x01;		//number of enabled pipes. enable only daya pipe0
RADIO_READWRITE(W, EN_RXADDR, val, 1);

val[0]=0x03; 		//ADDRESS width setup. 5 bytes
RADIO_READWRITE(W, SETUP_AW, val, 1);

val[0]=0x01; 		//RF channel setup. 2401 Mhz
RADIO_READWRITE(W, RF_CH, val, 1);

val[0] = 0x07; 		//RF setup. 0DB max power. 1 mbps max range
RADIO_READWRITE(W, RF_SETUP, val, 1);

val[0] = 0x12; 		//Tx RF_ADDRESS setup. address of the PRX device
val[1] = 0x12; 
val[2] = 0x12; 
val[3] = 0x12; 
val[4] = 0x12; 
RADIO_READWRITE(W, TX_ADDR, val, 5);

val[0]=0x01;		//payload width setup. 1 bytes
RADIO_READWRITE(W, RX_PW_P0, val, 1);

val[0]=0x0E;		// Config register. PTX + POWER UP + 2BYTE CRC
RADIO_READWRITE(W, CONFIG, val, 1);

_delay_ms(100); //give radio time to reach STANDBY mode (CE=low);

As suggested in a similar post here, i even tried adding a 22pf capacitor between the power and ground of NRF24L01+ but with no success.

Please help.

UPDATE:

I checked using polling as well (bit 5 on STATUS register) using the command

while((RADIO_GETSTATUS()&(1<<5))==0){}
PORTB |= (1<<PB0); //light GREEN LED

The LED does not light up ... so even the TX_DS bit is not getting set in the STATUS register.

On probing with logic analyzer,I get this

image description

after the toggle on CE line to TX the payload, I am continuously polling the status register (0x07) and continuously getting 0x0E