/**
* @file LoRaPHUS915.cpp
*
* @brief Implements LoRaPHY for US 915 MHz band
*
* \code
* ______ _
* / _____) _ | |
* ( (____ _____ ____ _| |_ _____ ____| |__
* \____ \| ___ | (_ _) ___ |/ ___) _ \
* _____) ) ____| | | || |_| ____( (___| | | |
* (______/|_____)_|_|_| \__)_____)\____)_| |_|
* (C)2013 Semtech
* ___ _____ _ ___ _ _____ ___ ___ ___ ___
* / __|_ _/_\ / __| |/ / __/ _ \| _ \/ __| __|
* \__ \ | |/ _ \ (__| ' <| _| (_) | / (__| _|
* |___/ |_/_/ \_\___|_|\_\_| \___/|_|_\\___|___|
* embedded.connectivity.solutions===============
*
* \endcode
*
*
* License: Revised BSD License, see LICENSE.TXT file include in the project
*
* Maintainer: Miguel Luis ( Semtech ), Gregory Cristian ( Semtech ) and Daniel Jaeckle ( STACKFORCE )
*
* Copyright (c) 2017, Arm Limited and affiliates.
* SPDX-License-Identifier: BSD-3-Clause
*
*/
#include <string.h>
#include "LoRaPHYUS915.h"
#include "lora_phy_ds.h"
/*!
* Minimal datarate that can be used by the node
*/
#define US915_TX_MIN_DATARATE DR_0
/*!
* Maximal datarate that can be used by the node
*/
#define US915_TX_MAX_DATARATE DR_4
/*!
* Minimal datarate that can be used by the node
*/
#define US915_RX_MIN_DATARATE DR_8
/*!
* Maximal datarate that can be used by the node
*/
#define US915_RX_MAX_DATARATE DR_13
/*!
* Default datarate used by the node
*/
#define US915_DEFAULT_DATARATE DR_0
/*!
* Minimal Rx1 receive datarate offset
*/
#define US915_MIN_RX1_DR_OFFSET 0
/*!
* Maximal Rx1 receive datarate offset
*/
#define US915_MAX_RX1_DR_OFFSET 3
/*!
* Default Rx1 receive datarate offset
*/
#define US915_DEFAULT_RX1_DR_OFFSET 0
/*!
* Minimal Tx output power that can be used by the node
*/
#define US915_MIN_TX_POWER TX_POWER_10
/*!
* Maximal Tx output power that can be used by the node
*/
#define US915_MAX_TX_POWER TX_POWER_0
/*!
* Default Tx output power used by the node
*/
#define US915_DEFAULT_TX_POWER TX_POWER_0
/*!
* Default Max ERP
*/
#define US915_DEFAULT_MAX_ERP 30.0f
/*!
* ADR Ack limit
*/
#define US915_ADR_ACK_LIMIT 64
/*!
* ADR Ack delay
*/
#define US915_ADR_ACK_DELAY 32
/*!
* Enabled or disabled the duty cycle
*/
#define US915_DUTY_CYCLE_ENABLED 0
/*!
* Maximum RX window duration
*/
#define US915_MAX_RX_WINDOW 3000
/*!
* Receive delay 1
*/
#define US915_RECEIVE_DELAY1 1000
/*!
* Receive delay 2
*/
#define US915_RECEIVE_DELAY2 2000
/*!
* Join accept delay 1
*/
#define US915_JOIN_ACCEPT_DELAY1 5000
/*!
* Join accept delay 2
*/
#define US915_JOIN_ACCEPT_DELAY2 6000
/*!
* Maximum frame counter gap
*/
#define US915_MAX_FCNT_GAP 16384
/*!
* Ack timeout
*/
#define US915_ACKTIMEOUT 2000
/*!
* Random ack timeout limits
*/
#define US915_ACK_TIMEOUT_RND 1000
/*!
* Second reception window channel frequency definition.
*/
#define US915_RX_WND_2_FREQ 923300000
/*!
* Second reception window channel datarate definition.
*/
#define US915_RX_WND_2_DR DR_8
/*!
* Band 0 definition
* { DutyCycle, TxMaxPower, LastJoinTxDoneTime, LastTxDoneTime, TimeOff }
*/
static const band_t US915_BAND0 = { 1, US915_MAX_TX_POWER, 0, 0, 0 }; // 100.0 %
/*!
* Defines the first channel for RX window 1 for US band
*/
#define US915_FIRST_RX1_CHANNEL ( (uint32_t) 923300000 )
/*!
* Defines the last channel for RX window 1 for US band
*/
#define US915_LAST_RX1_CHANNEL ( (uint32_t) 927500000 )
/*!
* Defines the step width of the channels for RX window 1
*/
#define US915_STEPWIDTH_RX1_CHANNEL ( (uint32_t) 600000 )
/*!
* Data rates table definition
*/
static const uint8_t datarates_US915[] = {10, 9, 8, 7, 8, 0, 0, 0, 12, 11, 10, 9, 8, 7, 0, 0};
/*!
* Bandwidths table definition in Hz
*/
static const uint32_t bandwidths_US915[] = {125000, 125000, 125000, 125000, 500000, 0, 0, 0, 500000, 500000, 500000, 500000, 500000, 500000, 0, 0};
/*!
* Up/Down link data rates offset definition
*/
static const int8_t datarate_offsets_US915[5][4] = {
{ DR_10, DR_9, DR_8, DR_8 }, // DR_0
{ DR_11, DR_10, DR_9, DR_8 }, // DR_1
{ DR_12, DR_11, DR_10, DR_9 }, // DR_2
{ DR_13, DR_12, DR_11, DR_10 }, // DR_3
{ DR_13, DR_13, DR_12, DR_11 }, // DR_4
};
/*!
* Maximum payload with respect to the datarate index. Cannot operate with repeater.
*/
static const uint8_t max_payloads_US915[] = {11, 53, 125, 242, 242, 0, 0, 0, 53, 129, 242, 242, 242, 242, 0, 0};
/*!
* Maximum payload with respect to the datarate index. Can operate with repeater.
*/
static const uint8_t max_payloads_with_repeater_US915[] = {11, 53, 125, 242, 242, 0, 0, 0, 33, 109, 222, 222, 222, 222, 0, 0};
static const uint16_t fsb_mask[] = MBED_CONF_LORA_FSB_MASK;
static const uint16_t full_channel_mask [] = {0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0x00FF};
LoRaPHYUS915::LoRaPHYUS915()
{
bands[0] = US915_BAND0;
// Channels
// 125 kHz channels - Upstream
for (uint8_t i = 0; i < US915_MAX_NB_CHANNELS - 8; i++) {
channels[i].frequency = 902300000 + i * 200000;
channels[i].dr_range.value = (DR_3 << 4) | DR_0;
channels[i].band = 0;
}
// 500 kHz channels - Upstream
for (uint8_t i = US915_MAX_NB_CHANNELS - 8; i < US915_MAX_NB_CHANNELS; i++) {
channels[i].frequency = 903000000 + (i - (US915_MAX_NB_CHANNELS - 8)) * 1600000;
channels[i].dr_range.value = (DR_4 << 4) | DR_4;
channels[i].band = 0;
}
// Fill-up default channel mask and apply FSB mask too
fill_channel_mask_with_fsb(full_channel_mask, fsb_mask,
default_channel_mask, US915_CHANNEL_MASK_SIZE);
memset(channel_mask, 0, sizeof(channel_mask));
memset(current_channel_mask, 0, sizeof(current_channel_mask));
// Copy channels default mask
copy_channel_mask(channel_mask, default_channel_mask, US915_CHANNEL_MASK_SIZE);
// current channel masks keep track of the
// channels previously used, i.e., which channels should be avoided in
// next transmission
copy_channel_mask(current_channel_mask, channel_mask, US915_CHANNEL_MASK_SIZE);
// set default channels
phy_params.channels.channel_list = channels;
phy_params.channels.channel_list_size = US915_MAX_NB_CHANNELS;
phy_params.channels.mask = channel_mask;
phy_params.channels.default_mask = default_channel_mask;
phy_params.channels.mask_size = US915_CHANNEL_MASK_SIZE;
// set bands for US915 spectrum
phy_params.bands.table = (void *) bands;
phy_params.bands.size = US915_MAX_NB_BANDS;
// set bandwidths available in US915 spectrum
phy_params.bandwidths.table = (void *) bandwidths_US915;
phy_params.bandwidths.size = 16;
// set data rates available in US915 spectrum
phy_params.datarates.table = (void *) datarates_US915;
phy_params.datarates.size = 16;
// set payload sizes with respect to data rates
phy_params.payloads.table = (void *) max_payloads_US915;
phy_params.payloads.size = 16;
phy_params.payloads_with_repeater.table = (void *) max_payloads_with_repeater_US915;
phy_params.payloads_with_repeater.size = 16;
// dwell time setting
phy_params.ul_dwell_time_setting = 0;
phy_params.dl_dwell_time_setting = 0;
// set initial and default parameters
phy_params.duty_cycle_enabled = US915_DUTY_CYCLE_ENABLED;
phy_params.accept_tx_param_setup_req = false;
phy_params.fsk_supported = false;
phy_params.cflist_supported = false;
phy_params.dl_channel_req_supported = false;
phy_params.custom_channelplans_supported = false;
phy_params.default_channel_cnt = US915_MAX_NB_CHANNELS;
phy_params.max_channel_cnt = US915_MAX_NB_CHANNELS;
phy_params.cflist_channel_cnt = 0;
phy_params.min_tx_datarate = US915_TX_MIN_DATARATE;
phy_params.max_tx_datarate = US915_TX_MAX_DATARATE;
phy_params.min_rx_datarate = US915_RX_MIN_DATARATE;
phy_params.max_rx_datarate = US915_RX_MAX_DATARATE;
phy_params.default_datarate = US915_DEFAULT_DATARATE;
phy_params.default_max_datarate = US915_TX_MAX_DATARATE;
phy_params.min_rx1_dr_offset = US915_MIN_RX1_DR_OFFSET;
phy_params.max_rx1_dr_offset = US915_MAX_RX1_DR_OFFSET;
phy_params.default_rx1_dr_offset = US915_DEFAULT_RX1_DR_OFFSET;
phy_params.min_tx_power = US915_MIN_TX_POWER;
phy_params.max_tx_power = US915_MAX_TX_POWER;
phy_params.default_tx_power = US915_DEFAULT_TX_POWER;
phy_params.default_max_eirp = 0;
phy_params.default_antenna_gain = 0;
phy_params.adr_ack_limit = US915_ADR_ACK_LIMIT;
phy_params.adr_ack_delay = US915_ADR_ACK_DELAY;
phy_params.max_rx_window = US915_MAX_RX_WINDOW;
phy_params.recv_delay1 = US915_RECEIVE_DELAY1;
phy_params.recv_delay2 = US915_RECEIVE_DELAY2;
phy_params.join_accept_delay1 = US915_JOIN_ACCEPT_DELAY1;
phy_params.join_accept_delay2 = US915_JOIN_ACCEPT_DELAY2;
phy_params.max_fcnt_gap = US915_MAX_FCNT_GAP;
phy_params.ack_timeout = US915_ACKTIMEOUT;
phy_params.ack_timeout_rnd = US915_ACK_TIMEOUT_RND;
phy_params.rx_window2_datarate = US915_RX_WND_2_DR;
phy_params.rx_window2_frequency = US915_RX_WND_2_FREQ;
}
LoRaPHYUS915::~LoRaPHYUS915()
{
}
int8_t LoRaPHYUS915::limit_tx_power(int8_t tx_power, int8_t max_band_tx_power,
int8_t datarate)
{
int8_t tx_power_out = tx_power;
// Limit tx power to the band max
tx_power_out = MAX(tx_power, max_band_tx_power);
if (datarate == DR_4) {
// Limit tx power to max 26dBm
tx_power_out = MAX(tx_power, TX_POWER_2);
} else {
if (num_active_channels(channel_mask, 0, 4) < 50) {
// Limit tx power to max 21dBm
tx_power_out = MAX(tx_power, TX_POWER_5);
}
}
return tx_power_out;
}
void LoRaPHYUS915::restore_default_channels()
{
// Copy channels default mask
copy_channel_mask(channel_mask, default_channel_mask, US915_CHANNEL_MASK_SIZE);
// Update running channel mask
intersect_channel_mask(channel_mask, current_channel_mask, US915_CHANNEL_MASK_SIZE);
}
bool LoRaPHYUS915::rx_config(rx_config_params_t *config)
{
int8_t dr = config->datarate;
uint8_t max_payload = 0;
int8_t phy_dr = 0;
uint32_t frequency = config->frequency;
_radio->lock();
if (_radio->get_status() != RF_IDLE) {
_radio->unlock();
return false;
}
_radio->unlock();
// For US915 spectrum, we have 8 Downstream channels, MAC would have
// selected a channel randomly from 72 Upstream channels, that index is
// passed in rx_config_params_t. Based on that channel index, we choose the
// frequency for first RX slot
if (config->rx_slot == RX_SLOT_WIN_1) {
// Apply window 1 frequency
frequency = US915_FIRST_RX1_CHANNEL + (config->channel % 8) * US915_STEPWIDTH_RX1_CHANNEL;
// Caller may print the frequency to log so update it to match actual frequency
config->frequency = frequency;
}
// Read the physical datarate from the datarates table
phy_dr = datarates_US915[dr];
_radio->lock();
_radio->set_channel(frequency);
// Radio configuration
_radio->set_rx_config(MODEM_LORA, config->bandwidth, phy_dr, 1, 0,
MBED_CONF_LORA_DOWNLINK_PREAMBLE_LENGTH,
config->window_timeout, false, 0, false, 0, 0, true,
config->is_rx_continuous);
_radio->unlock();
if (config->is_repeater_supported == true) {
max_payload = max_payloads_with_repeater_US915[dr];
} else {
max_payload = max_payloads_US915[dr];
}
_radio->lock();
_radio->set_max_payload_length(MODEM_LORA, max_payload + LORA_MAC_FRMPAYLOAD_OVERHEAD);
_radio->unlock();
return true;
}
bool LoRaPHYUS915::tx_config(tx_config_params_t *config, int8_t *tx_power,
lorawan_time_t *tx_toa)
{
int8_t phy_dr = datarates_US915[config->datarate];
int8_t tx_power_limited = limit_tx_power(config->tx_power,
bands[channels[config->channel].band].max_tx_pwr,
config->datarate);
uint32_t bandwidth = get_bandwidth(config->datarate);
int8_t phy_tx_power = 0;
// Calculate physical TX power
phy_tx_power = compute_tx_power(tx_power_limited, US915_DEFAULT_MAX_ERP, 0);
_radio->lock();
_radio->set_channel(channels[config->channel].frequency);
_radio->set_tx_config(MODEM_LORA, phy_tx_power, 0, bandwidth, phy_dr, 1,
MBED_CONF_LORA_UPLINK_PREAMBLE_LENGTH,
false, true, 0, 0, false, 3000);
// Setup maximum payload lenght of the radio driver
_radio->set_max_payload_length(MODEM_LORA, config->pkt_len);
// Get the time-on-air of the next tx frame
*tx_toa = _radio->time_on_air(MODEM_LORA, config->pkt_len);
_radio->unlock();
*tx_power = tx_power_limited;
return true;
}
uint8_t LoRaPHYUS915::link_ADR_request(adr_req_params_t *params,
int8_t *dr_out, int8_t *tx_power_out,
uint8_t *nb_rep_out, uint8_t *nb_bytes_parsed)
{
uint8_t status = 0x07;
link_adr_params_t adr_settings;
uint8_t next_idx = 0;
uint8_t bytes_processed = 0;
uint16_t temp_channel_masks[US915_CHANNEL_MASK_SIZE] = {0, 0, 0, 0, 0};
verify_adr_params_t verify_params;
// Initialize local copy of channels mask
copy_channel_mask(temp_channel_masks, channel_mask, US915_CHANNEL_MASK_SIZE);
while (bytes_processed < params->payload_size &&
params->payload[bytes_processed] == SRV_MAC_LINK_ADR_REQ) {
next_idx = parse_link_ADR_req(&(params->payload[bytes_processed]),
params->payload_size - bytes_processed,
&adr_settings);
if (next_idx == 0) {
bytes_processed = 0;
// break loop, malformed packet
break;
}
// Update bytes processed
bytes_processed += next_idx;
// Revert status, as we only check the last ADR request for the channel mask KO
status = 0x07;
if (adr_settings.ch_mask_ctrl == 6) {
// Enable all 125 kHz channels
fill_channel_mask_with_value(temp_channel_masks, 0xFFFF,
US915_CHANNEL_MASK_SIZE - 1);
// Apply chMask to channels 64 to 71
temp_channel_masks[4] = adr_settings.channel_mask;
} else if (adr_settings.ch_mask_ctrl == 7) {
// Disable all 125 kHz channels
fill_channel_mask_with_value(temp_channel_masks, 0x0000,
US915_CHANNEL_MASK_SIZE - 1);
// Apply chMask to channels 64 to 71
temp_channel_masks[4] = adr_settings.channel_mask;
} else if (adr_settings.ch_mask_ctrl == 5) {
// RFU
status &= 0xFE; // Channel mask KO
} else {
temp_channel_masks[adr_settings.ch_mask_ctrl] = adr_settings.channel_mask;
}
}
if (bytes_processed == 0) {
*nb_bytes_parsed = 0;
return status;
}
// FCC 15.247 paragraph F mandates to hop on at least 2 125 kHz channels
if ((adr_settings.datarate < DR_4) &&
(num_active_channels(temp_channel_masks, 0, 4) < 2)) {
status &= 0xFE; // Channel mask KO
}
verify_params.status = status;
verify_params.adr_enabled = params->adr_enabled;
verify_params.datarate = adr_settings.datarate;
verify_params.tx_power = adr_settings.tx_power;
verify_params.nb_rep = adr_settings.nb_rep;
verify_params.current_datarate = params->current_datarate;
verify_params.current_tx_power = params->current_tx_power;
verify_params.current_nb_rep = params->current_nb_trans;
verify_params.channel_mask = temp_channel_masks;
// Verify the parameters and update, if necessary
status = verify_link_ADR_req(&verify_params, &adr_settings.datarate,
&adr_settings.tx_power, &adr_settings.nb_rep);
// Update channelsMask if everything is correct
if (status == 0x07) {
// Copy Mask
copy_channel_mask(channel_mask, temp_channel_masks, US915_CHANNEL_MASK_SIZE);
// update running channel mask
intersect_channel_mask(channel_mask, current_channel_mask,
US915_CHANNEL_MASK_SIZE);
}
// Update status variables
*dr_out = adr_settings.datarate;
*tx_power_out = adr_settings.tx_power;
*nb_rep_out = adr_settings.nb_rep;
*nb_bytes_parsed = bytes_processed;
return status;
}
uint8_t LoRaPHYUS915::accept_rx_param_setup_req(rx_param_setup_req_t *params)
{
uint8_t status = 0x07;
uint32_t freq = params->frequency;
// Verify radio frequency
if ((_radio->check_rf_frequency(freq) == false)
|| (freq < US915_FIRST_RX1_CHANNEL)
|| (freq > US915_LAST_RX1_CHANNEL)
|| (((freq - (uint32_t) US915_FIRST_RX1_CHANNEL) % (uint32_t) US915_STEPWIDTH_RX1_CHANNEL) != 0)) {
status &= 0xFE; // Channel frequency KO
}
// Verify datarate
if (val_in_range(params->datarate, US915_RX_MIN_DATARATE, US915_RX_MAX_DATARATE) == 0) {
status &= 0xFD; // Datarate KO
}
if ((val_in_range(params->datarate, DR_5, DR_7)) || (params->datarate > DR_13)) {
status &= 0xFD; // Datarate KO
}
// Verify datarate offset
if (val_in_range(params->dr_offset, US915_MIN_RX1_DR_OFFSET, US915_MAX_RX1_DR_OFFSET) == 0) {
status &= 0xFB; // Rx1DrOffset range KO
}
return status;
}
int8_t LoRaPHYUS915::get_alternate_DR(uint8_t nb_trials)
{
int8_t datarate = 0;
if ((nb_trials & 0x01) == 0x01) {
datarate = DR_4;
} else {
datarate = DR_0;
}
return datarate;
}
lorawan_status_t LoRaPHYUS915::set_next_channel(channel_selection_params_t *params,
uint8_t *channel, lorawan_time_t *time,
lorawan_time_t *aggregate_timeOff)
{
uint8_t nb_enabled_channels = 0;
uint8_t delay_tx = 0;
uint8_t enabled_channels[US915_MAX_NB_CHANNELS] = {0};
lorawan_time_t next_tx_delay = 0;
// Count 125kHz channels
if (num_active_channels(current_channel_mask, 0, 4) == 0) {
// If none of the 125 kHz Upstream channel found,
// Reactivate default channels
copy_channel_mask(current_channel_mask, channel_mask, 4);
}
// Update the 500 kHz channels in the running mask
if ((params->current_datarate >= DR_4)
&& (current_channel_mask[4] & 0x00FF) == 0) {
current_channel_mask[4] = channel_mask[4];
}
if (params->aggregate_timeoff <= _lora_time->get_elapsed_time(params->last_aggregate_tx_time)) {
// Reset Aggregated time off
*aggregate_timeOff = 0;
// Update bands Time OFF
next_tx_delay = update_band_timeoff(params->joined, params->dc_enabled, bands, US915_MAX_NB_BANDS);
// Search how many channels are enabled
nb_enabled_channels = enabled_channel_count(params->current_datarate,
current_channel_mask,
enabled_channels, &delay_tx);
} else {
delay_tx++;
next_tx_delay = params->aggregate_timeoff - _lora_time->get_elapsed_time(params->last_aggregate_tx_time);
}
if (nb_enabled_channels > 0) {
// We found a valid channel
*channel = enabled_channels[get_random(0, nb_enabled_channels - 1)];
// Disable the channel in the mask
disable_channel(current_channel_mask, *channel, US915_MAX_NB_CHANNELS);
*time = 0;
return LORAWAN_STATUS_OK;
} else {
if (delay_tx > 0) {
// Delay transmission due to AggregatedTimeOff or to a band time off
*time = next_tx_delay;
return LORAWAN_STATUS_DUTYCYCLE_RESTRICTED;
}
// Datarate not supported by any channel
*time = 0;
return LORAWAN_STATUS_NO_CHANNEL_FOUND;
}
}
void LoRaPHYUS915::set_tx_cont_mode(cw_mode_params_t *params, uint32_t given_frequency)
{
(void)given_frequency;
int8_t tx_power_limited = limit_tx_power(params->tx_power,
bands[channels[params->channel].band].max_tx_pwr,
params->datarate);
int8_t phyTxPower = 0;
uint32_t frequency = channels[params->channel].frequency;
// Calculate physical TX power
phyTxPower = compute_tx_power(tx_power_limited, US915_DEFAULT_MAX_ERP, 0);
_radio->lock();
_radio->set_tx_continuous_wave(frequency, phyTxPower, params->timeout);
_radio->unlock();
}
uint8_t LoRaPHYUS915::apply_DR_offset(int8_t dr, int8_t dr_offset)
{
return datarate_offsets_US915[dr][dr_offset];
}
void LoRaPHYUS915::intersect_channel_mask(const uint16_t *source,
uint16_t *destination, uint8_t size)
{
for (uint8_t i = 0; i < size; i++) {
destination[i] &= source[i];
}
}
void LoRaPHYUS915::fill_channel_mask_with_fsb(const uint16_t *expectation,
const uint16_t *fsb_mask,
uint16_t *destination,
uint8_t size)
{
for (uint8_t i = 0; i < size; i++) {
destination[i] = expectation[i] & fsb_mask[i];
}
}
void LoRaPHYUS915::fill_channel_mask_with_value(uint16_t *channel_mask,
uint16_t value, uint8_t size)
{
for (uint8_t i = 0; i < size; i++) {
channel_mask[i] = value;
}
}
