NRF24LE1

[a.serhatboz]

Hello, first of all, I am an engineering student. I want to learn communication and I just started it. I don't understand exactly what the following lines do. How can I do? What are the current resources? I couldn't understand the following lines of code.... Waiting for your support. ((The codes are completely taken from (enhanced_shockburst_ptx_nrf24le1.uvproj))

What part of the code does the actual work? Where is the ACK part? I don't want ACK and I want to work at 1 Mbps.

I don't know about addressing either, I don't know where to start :)

Thank you from now...

[a.serhatboz]

Hello, first of all, thank you. I have read the codes many times but I don't know. Normally the receiver should not receive data from different addresses, but my receiver does. I leave my schematic, codes and more. thanks 

[ovrebekk]

Hi

I dug out my old nRF24LE1 kits and tested the standard examples, with some code added to simulate your changes (like the modified address). 

One thing I realized is that in order to properly update the address you need to set both the TX and the PIPE0 address on the PTX side, otherwise the transmission won't work properly. 

The PTX will essentially send the packet using the TX address, and look for the ACK on the PIPE0 address, so in order to have successful communication with ACK you need to set these two addresses identically. 

Could you try to make this change and see if it works better?

If needed I have attached my main files below:

Fullscreen main_ptx.c Download

/* Copyright (c) 2009 Nordic Semiconductor. All Rights Reserved.
 *
 * The information contained herein is property of Nordic Semiconductor ASA.
 * Terms and conditions of usage are described in detail in NORDIC
 * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
 *
 * Licensees are granted free, non-transferable use of the information. NO
 * WARRENTY of ANY KIND is provided. This heading must NOT be removed from
 * the file.
 *
 * $LastChangedRevision: 2513 $
 */

/** @file
 * @brief Enhanced ShockBurst Primary Transmitter example
 * @defgroup esb_ptx_example Enhanced ShockBurst Primary Transmitter (PTX) example
 * @{
 * @ingroup nrf_examples
 *
 * @brief This example sends packets continuously. The contents of P0 are
 * sent in the first payload byte (byte 0).
 *
 * The example shows the minimum required setup for transmitting packets to a
 * primary receiver (PRX) device.
 *
 * The following default radio parameters are being used:
 * - RF channel 2
 * - 2 Mbps data rate
 * - TX address 0xE7E7E7E7E7
 * - 1 byte CRC
 *
 * The project @ref esb_prx_example can be used as a counterpart for receiving the data.
 *
*/

//lint -e717
//lint -e714
//lint -e640

#ifdef MCU_NRF24LE1
#include "nrf24le1.h"
#include "hal_clk.h"
#endif

#ifdef MCU_NRF24LU1P
#include "nrf24lu1p.h"
#endif

#include <stdint.h>
#include <stdbool.h>
#include "hal_nrf.h"
#ifndef MCU_NRF24LU1P
#include "hal_clk.h" //lint !e322 !e7 "include file not found"
#endif

// Global variables
static bool volatile radio_busy;

uint8_t address[5]={0xB3,0xB4,0xB5,0xB6,0xF2};

void main(void)
{
  uint8_t payload[3];

  #ifdef MCU_NRF24LE1
  while(hal_clk_get_16m_source() != HAL_CLK_XOSC16M)
  {
    // Wait until 16 MHz crystal oscillator is running
  }
  #endif

  #ifdef MCU_NRF24LU1P
  // Enable radio SPI
  RFCTL = 0x10U;
  #endif

  // Enable the radio clock
  RFCKEN = 1U;

  // Enable RF interrupt
  RF = 1U;

  // Enable global interrupt
  EA = 1U;

  hal_nrf_set_address_width(HAL_NRF_AW_5BYTES); // 5 bytes address width
  hal_nrf_set_address(HAL_NRF_PIPE0, address); // Set device's addresses
  hal_nrf_set_address(HAL_NRF_TX, address); // Set device's addresses
  
  // Power up radio
  hal_nrf_set_power_mode(HAL_NRF_PWR_UP);

  for(;;)
  {
    // Put P0 contents in payload[0]
    payload[0] = ~P0;

    // Write payload to radio TX FIFO
    hal_nrf_write_tx_payload(payload, 3U);

    // Toggle radio CE signal to start transmission
    CE_PULSE();

    radio_busy = true;
    // Wait for radio operation to finish
    while (radio_busy)
    {
    }
  }
}

// Radio interrupt
NRF_ISR()
{
  uint8_t irq_flags;

  // Read and clear IRQ flags from radio
  irq_flags = hal_nrf_get_clear_irq_flags();

  switch(irq_flags)
  {
    // Transmission success
    case (1 << (uint8_t)HAL_NRF_TX_DS):
      radio_busy = false;
      // Data has been sent
      break;
    // Transmission failed (maximum re-transmits)
    case (1 << (uint8_t)HAL_NRF_MAX_RT):
      // When a MAX_RT interrupt occurs the TX payload will not be removed from the TX FIFO.
      // If the packet is to be discarded this must be done manually by flushing the TX FIFO.
      // Alternatively, CE_PULSE() can be called re-starting transmission of the payload.
      // (Will only be possible after the radio irq flags are cleared)
      hal_nrf_flush_tx();
      radio_busy = false;
      break;
    default:
      break;
  }
}
/** @} */

Fullscreen main_prx.c Download

/* Copyright (c) 2009 Nordic Semiconductor. All Rights Reserved.
 *
 * The information contained herein is confidential property of Nordic
 * Semiconductor ASA.Terms and conditions of usage are described in detail
 * in NORDIC SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
 *
 * Licensees are granted free, non-transferable use of the information. NO
 * WARRENTY of ANY KIND is provided. This heading must NOT be removed from
 * the file.
 *
 * $LastChangedRevision: 2211 $
 */

/** @file
 * @brief Enhanced ShockBurst Primary Receiver example
 * @defgroup esb_prx_example Enhanced ShockBurst Primary Receiver (PRX) example
 * @{
 * @ingroup nrf_examples
 *
 * @brief This example monitors for data and writes the first byte (byte 0) of the
 * received payloads to P0.
 *
 * The example shows the minimum required setup for receiving packets from a
 * primary transmitter (PTX) device.
 *
 * The following default radio parameters are being used:
 * - RF channel 2
 * - 2 Mbps data rate
 * - RX address 0xE7E7E7E7E7 (pipe 0) and 0xC2C2C2C2C2 (pipe 1)
 * - 1 byte CRC
 *
 * The project @ref esb_ptx_example can be used as a counterpart for transmitting the data.
 *
*/

//lint -e717
//lint -e534
//lint -e714
//lint -e783

#ifdef MCU_NRF24LE1
#include "nrf24le1.h"
#include "hal_clk.h"
#endif

#ifdef MCU_NRF24LU1P
#include "nrf24lu1p.h"
#endif

#include <stdint.h>
#include "hal_nrf.h"

// Global variables
uint8_t payload[3];

uint8_t address[5]={0xB3,0xB4,0xB5,0xB6,0xF2};

void main()
{
#ifdef MCU_NRF24LE1
  while(hal_clk_get_16m_source() != HAL_CLK_XOSC16M)
  {
    // Wait until 16 MHz crystal oscillator is running
  }
#endif
  
  #ifdef MCU_NRF24LU1P
  // Enable radio SPI
  RFCTL = 0x10;
  #endif

  // Set P0 as output
  P0DIR = 0;

  // Enable the radio clock
  RFCKEN = 1;

  // Enable RF interrupt
  RF = 1;
  // Enable global interrupt
  EA = 1;

  // Configure radio as primary receiver (PTX)
  hal_nrf_set_operation_mode(HAL_NRF_PRX);

  // Set payload width to 3 bytes
  hal_nrf_set_rx_payload_width((int)HAL_NRF_PIPE0, 3);
  
  hal_nrf_set_address_width(HAL_NRF_AW_5BYTES); // 5 bytes address width
  hal_nrf_set_address(HAL_NRF_PIPE0, address); // Set device's addresses

  // Power up radio
  hal_nrf_set_power_mode(HAL_NRF_PWR_UP);

  // Enable receiver
  CE_HIGH();

  for(;;){}
}

// Radio interrupt
NRF_ISR()
{
  uint8_t irq_flags;

  // Read and clear IRQ flags from radio
  irq_flags = hal_nrf_get_clear_irq_flags();

  // If data received
  if((irq_flags & (1<<(uint8_t)HAL_NRF_RX_DR)) > 0)
  {
    // Read payload
    while(!hal_nrf_rx_fifo_empty())
    {
      hal_nrf_read_rx_payload(payload);
    }

    // Write received payload[0] to port 0
    P0 = payload[0];
  }
}
/** @} */

Best regards
Torbjørn