/*! ----------------------------------------------------------------------------
* @file main.c
* @brief Automatically Acknowledged data RX example code
*
* This is a simple code example that turns on the DW1000 receiver to receive a frame, (expecting the frame as sent by the companion simple
* example "ACK DATA TX"). The DW1000 is configured so that when a correctly addressed data frame is received with the ACK request (AR) bit
* set in the frame control field, the DW1000 will automatically respond with an ACK frame. The code loops after each frame reception to
* await another frame.
*
* @attention
*
* Copyright 2016 (c) Decawave Ltd, Dublin, Ireland.
*
* All rights reserved.
*
* @author Decawave
*/
#include "deca_device_api.h"
#include "deca_regs.h"
#include "lcd.h"
#include "port.h"
/* Example application name and version to display on LCD screen. */
#define APP_NAME "ACK DATA RX v1.0"
/* Default communication configuration. We use here EVK1000's default mode (mode 3). */
static dwt_config_t config = {
2, /* Channel number. */
DWT_PRF_64M, /* Pulse repetition frequency. */
DWT_PLEN_1024, /* Preamble length. Used in TX only. */
DWT_PAC32, /* Preamble acquisition chunk size. Used in RX only. */
9, /* TX preamble code. Used in TX only. */
9, /* RX preamble code. Used in RX only. */
1, /* 0 to use standard SFD, 1 to use non-standard SFD. */
DWT_BR_110K, /* Data rate. */
DWT_PHRMODE_STD, /* PHY header mode. */
(1025 + 64 - 32) /* SFD timeout (preamble length + 1 + SFD length - PAC size). Used in RX only. */
};
/* PAN ID/EUI/short address. See NOTE 1 and 2 below. */
static uint16 pan_id = 0xDECA;
static uint8 eui[] = {'A', 'C', 'K', 'D', 'A', 'T', 'R', 'X'};
static uint16 short_addr = 0x5258; /* "RX" */
/* Buffer to store received frame. See NOTE 3 below. */
#define FRAME_LEN_MAX 127
static uint8 rx_buffer[FRAME_LEN_MAX];
/* ACK request bit mask in DATA and MAC COMMAND frame control's first byte. */
#define FCTRL_ACK_REQ_MASK 0x20
/* Hold copy of status register state here for reference so that it can be examined at a debug breakpoint. */
static uint32 status_reg = 0;
/* Hold copy of frame length of frame received (if good) so that it can be examined at a debug breakpoint. */
static uint16 frame_len = 0;
/**
* Application entry point.
*/
int main(void)
{
/* Start with board specific hardware init. */
peripherals_init();
/* Display application name on LCD. */
lcd_display_str(APP_NAME);
/* Reset and initialise DW1000. See NOTE 4 below.
* For initialisation, DW1000 clocks must be temporarily set to crystal speed. After initialisation SPI rate can be increased for optimum
* performance. */
reset_DW1000(); /* Target specific drive of RSTn line into DW1000 low for a period. */
spi_set_rate_low();
if (dwt_initialise(DWT_LOADNONE) == DWT_ERROR)
{
lcd_display_str("INIT FAILED");
while (1)
{ };
}
spi_set_rate_high();
/* Configure DW1000. See NOTE 5 below. */
dwt_configure(&config);
/* Set PAN ID, EUI and short address. See NOTE 2 below. */
dwt_setpanid(pan_id);
dwt_seteui(eui);
dwt_setaddress16(short_addr);
/* Configure frame filtering. Only data frames are enabled in this example. Frame filtering must be enabled for Auto ACK to work. */
dwt_enableframefilter(DWT_FF_DATA_EN);
/* Activate auto-acknowledgement. Time is set to 0 so that the ACK is sent as soon as possible after reception of a frame. */
dwt_enableautoack(0);
/* Loop forever receiving frames. */
while (1)
{
/* Activate reception immediately. See NOTE 6 below. */
dwt_rxenable(0);
/* Poll until a frame is properly received or an RX error occurs. See NOTE 7 below.
* STATUS register is 5 bytes long but we are not interested in the high byte here, so we read a more manageable 32-bits with this API call. */
while (!((status_reg = dwt_read32bitreg(SYS_STATUS_ID)) & (SYS_STATUS_RXFCG | SYS_STATUS_ALL_RX_ERR)))
{ };
if (status_reg & SYS_STATUS_RXFCG)
{
/* Clear good RX frame event in the DW1000 status register. */
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_RXFCG);
/* A frame has been received, read it into the local buffer. */
frame_len = dwt_read32bitreg(RX_FINFO_ID) & RX_FINFO_RXFL_MASK_1023;
if (frame_len <= FRAME_LEN_MAX)
{
dwt_readrxdata(rx_buffer, frame_len, 0);
}
/* TESTING BREAKPOINT LOCATION #1 */
/* Since the auto ACK feature is enabled, an ACK should be sent if the received frame requests it, so we await the ACK TX completion
* before taking next action. See NOTE 8 below. */
if (rx_buffer[0] & FCTRL_ACK_REQ_MASK)
{
/* Poll DW1000 until confirmation of transmission of the ACK frame. */
while (!((status_reg = dwt_read32bitreg(SYS_STATUS_ID)) & SYS_STATUS_TXFRS))
{ };
/* Clear TXFRS event. */
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_TXFRS);
}
}
else
{
/* Clear RX error events in the DW1000 status register. */
dwt_write32bitreg(SYS_STATUS_ID, SYS_STATUS_ALL_RX_ERR);
}
}
}
/*****************************************************************************************************************************************************
* NOTES:
*
* 1. PAN ID, EUI and short address are hard coded constants to keep the example simple but for a real product every device should have a unique ID.
* For development purposes it is possible to generate a DW1000 unique ID by combining the Lot ID & Part Number values programmed into the DW1000
* during its manufacture. However there is no guarantee this will not conflict with someone else�s implementation. We recommended that customers
* buy a block of addresses from the IEEE Registration Authority for their production items. See "EUI" in the DW1000 User Manual.
* 2. EUI64 is not actually used in this example but the DW1000 is set up with this dummy value, to have it set to something. This would be required
* for a real application, i.e. because short addresses (and PAN ID) are typically assigned by a PAN coordinator.
* 3. In this example, maximum frame length is set to 127 bytes which is 802.15.4 UWB standard maximum frame length. DW1000 supports an extended frame
* length (up to 1023 bytes long) mode which is not used in this example.
* 4. In this example, LDE microcode is not loaded upon calling dwt_initialise(). This will prevent the IC from generating an RX timestamp. If
* time-stamping is required, DWT_LOADUCODE parameter should be used. See two-way ranging examples (e.g. examples 5a/5b).
* 5. In a real application, for optimum performance within regulatory limits, it may be necessary to set TX pulse bandwidth and TX power, (using
* the dwt_configuretxrf API call) to per device calibrated values saved in the target system or the DW1000 OTP memory.
* 6. Manual reception activation is performed here but DW1000 offers several features that can be used to handle more complex scenarios or to
* optimise system's overall performance (e.g. timeout after a given time, automatic re-enabling of reception in case of errors, etc.).
* 7. We use polled mode of operation here to keep the example as simple as possible but all status events can be used to generate interrupts. Please
* refer to DW1000 User Manual for more details on "interrupts".
* 8. This is the purpose of the AAT bit in DW1
