neptunium-firmware/Drivers/sx126x_driver/src/sx126x_lr_fhss.c
Peter aa3b50eed2 Initial commit. Logging using tinyusb on stm32f302c8t6. WORKING:
WORKING: lps22hb, lsm6dsox, neo-m9n
TODO: sx1262, SD card, freertos
2024-07-06 04:25:33 +08:00

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C

/**
* @file sx126x_lr_fhss.c
*
* @brief SX126x LR-FHSS driver implementation
*
* The Clear BSD License
* Copyright Semtech Corporation 2021. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted (subject to the limitations in the disclaimer
* below) provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the Semtech corporation nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED BY
* THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
* NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SEMTECH CORPORATION BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* -----------------------------------------------------------------------------
* --- DEPENDENCIES ------------------------------------------------------------
*/
#include "lr_fhss_mac.h"
#include "sx126x_lr_fhss.h"
#include "sx126x_hal.h"
/*
* -----------------------------------------------------------------------------
* --- PRIVATE MACROS-----------------------------------------------------------
*/
/*
* -----------------------------------------------------------------------------
* --- PRIVATE CONSTANTS -------------------------------------------------------
*/
/* \cond */
#define SX126X_SET_MODULATION_PARAMS ( 0x8B )
#define SX126X_SET_PKT_PARAMS ( 0x8C )
#define SX126X_LR_FHSS_DISABLE_HOPPING ( 0 )
#define SX126X_LR_FHSS_ENABLE_HOPPING ( 1 )
#define SX126X_LR_FHSS_HOP_TABLE_SIZE ( 16 )
#define SX126X_LR_FHSS_HOP_ENTRY_SIZE ( 6 )
#define SX126X_LR_FHSS_GRID_3906_HZ_PLL_STEPS ( 4096 )
#define SX126X_LR_FHSS_GRID_25391_HZ_PLL_STEPS ( 26624 )
#define SX126X_LR_FHSS_GRID_INDEX_TO_PLL_STEPS ( 512 )
/* \endcond */
/*
* -----------------------------------------------------------------------------
* --- PRIVATE TYPES -----------------------------------------------------------
*/
/*
* -----------------------------------------------------------------------------
* --- PRIVATE VARIABLES -------------------------------------------------------
*/
/*
* -----------------------------------------------------------------------------
* --- PRIVATE FUNCTION DECLARATIONS -------------------------------------------
*/
/**
* @brief Configure the radio to perform frequency hopping
*
* @param [in] context Chip implementation context
* @param [in] nb_bytes Total number of bytes
* @param [in] nb_hops Total number of hops
*
* @returns Operation status
*/
sx126x_status_t sx126x_lr_fhss_write_hop_config( const void* context, const uint8_t nb_bytes, const uint8_t nb_hops );
/**
* @brief Write a hop frequency/duration pair to the radio hop table
*
* @param [in] context Chip implementation context
* @param [in] index Index to chip hop table
* @param [in] nb_symbols Hop duration in symbols
* @param [in] freq_in_pll_steps Hop frequency, in PLL steps
*
* @returns Operation status
*/
sx126x_status_t sx126x_lr_fhss_write_hop( const void* context, const uint8_t index, const uint16_t nb_symbols,
const uint32_t freq_in_pll_steps );
/**
* @brief Get Frequency, in PLL steps, of the next hop
*
* @param [in] params sx126x LR-FHSS parameter structure
* @param [out] state sx126x LR-FHSS state structure that will be initialized by this function
*
* @returns Frequency, in PLL steps, of the next hop
*/
uint32_t sx126x_lr_fhss_get_next_freq_in_pll_steps( const sx126x_lr_fhss_params_t* params,
sx126x_lr_fhss_state_t* state );
/**
* @brief Get grid frequency, in PLL steps
*
* @param [in] params sx126x LR-FHSS parameter structure
*
* @returns Grid frequency, in PLL steps
*/
static inline unsigned int sx126x_lr_fhss_get_grid_in_pll_steps( const sx126x_lr_fhss_params_t* params );
/*
* -----------------------------------------------------------------------------
* --- PUBLIC FUNCTIONS DEFINITION ---------------------------------------------
*/
sx126x_status_t sx126x_lr_fhss_init( const void* context, const sx126x_lr_fhss_params_t* params )
{
const uint8_t pkt_params_buf[] = {
SX126X_SET_PKT_PARAMS, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
const uint8_t mod_params_buf[] = {
SX126X_SET_MODULATION_PARAMS, 32, 0, 0, SX126X_GFSK_PULSE_SHAPE_BT_1, 0, 0, 0, 0,
};
sx126x_status_t status = sx126x_set_pkt_type( context, SX126X_PKT_TYPE_LR_FHSS );
if( status != SX126X_STATUS_OK )
{
return status;
}
status = ( sx126x_status_t ) sx126x_hal_write( context, pkt_params_buf, sizeof( pkt_params_buf ), 0, 0 );
if( status != SX126X_STATUS_OK )
{
return status;
}
status = ( sx126x_status_t ) sx126x_hal_write( context, mod_params_buf, sizeof( mod_params_buf ), 0, 0 );
if( status != SX126X_STATUS_OK )
{
return status;
}
status = sx126x_set_buffer_base_address( context, 0x00, 0x00 );
return status;
}
uint16_t sx126x_lr_fhss_get_bit_delay_in_us( const sx126x_lr_fhss_params_t* params, uint16_t payload_length )
{
lr_fhss_digest_t digest;
lr_fhss_process_parameters( &params->lr_fhss_params, payload_length, &digest );
const uint8_t nb_padding_bits = 1 + ( ( 32768 - digest.nb_bits ) & 0x07 );
return 1550 + nb_padding_bits * 2048;
}
sx126x_status_t sx126x_lr_fhss_process_parameters( const sx126x_lr_fhss_params_t* params, uint16_t hop_sequence_id,
uint16_t payload_length, sx126x_lr_fhss_state_t* state )
{
lr_fhss_process_parameters( &params->lr_fhss_params, payload_length, &state->digest );
if( state->digest.nb_bytes > LR_FHSS_MAX_PHY_PAYLOAD_BYTES )
{
return SX126X_STATUS_UNKNOWN_VALUE;
}
if( params->lr_fhss_params.grid == LR_FHSS_V1_GRID_25391_HZ )
{
if( params->device_offset > 25 || params->device_offset < -26 )
{
return SX126X_STATUS_UNKNOWN_VALUE;
}
if( params->lr_fhss_params.bw < LR_FHSS_V1_BW_722656_HZ )
{
return SX126X_STATUS_UNKNOWN_VALUE;
}
}
if( params->lr_fhss_params.grid == LR_FHSS_V1_GRID_3906_HZ )
{
if( params->device_offset > 3 || params->device_offset < -4 )
{
return SX126X_STATUS_UNKNOWN_VALUE;
}
}
// Initialize hop index and params
state->current_hop = 0;
lr_fhss_status_t status =
lr_fhss_get_hop_params( &params->lr_fhss_params, &state->hop_params, &state->lfsr_state, hop_sequence_id );
if( status != LR_FHSS_STATUS_OK )
{
return ( sx126x_status_t ) status;
}
// Skip the hop frequencies inside the set [0, 4 - header_count):
if( params->lr_fhss_params.enable_hopping != 0 )
{
for( int i = 0; i < 4 - params->lr_fhss_params.header_count; ++i )
{
lr_fhss_get_next_state( &state->lfsr_state, &state->hop_params );
}
}
state->next_freq_in_pll_steps = sx126x_lr_fhss_get_next_freq_in_pll_steps( params, state );
return SX126X_STATUS_OK;
}
sx126x_status_t sx126x_lr_fhss_write_hop_sequence_head( const void* context, const sx126x_lr_fhss_params_t* params,
sx126x_lr_fhss_state_t* state )
{
sx126x_status_t status = sx126x_lr_fhss_write_hop_config( context, state->digest.nb_bytes, state->digest.nb_hops );
if( status != SX126X_STATUS_OK )
{
return status;
}
const uint16_t pulse_shape_compensation = 1;
if( params->lr_fhss_params.enable_hopping == 0 )
{
// (LR_FHSS_HEADER_BITS + pulse_shape_compensation) symbols on first sync_word, LR_FHSS_HEADER_BITS on next
// sync_words, LR_FHSS_BLOCK_BITS on payload
const uint16_t nb_symbols = state->digest.nb_bits + pulse_shape_compensation;
status = sx126x_lr_fhss_write_hop( context, state->current_hop, nb_symbols, state->next_freq_in_pll_steps );
if( status != SX126X_STATUS_OK )
{
return status;
}
state->current_hop++;
state->digest.nb_bits = 0;
}
else
{
// fill at most SX126X_LR_FHSS_HOP_TABLE_SIZE hops of the hardware hop table
uint8_t truncated_hops = state->digest.nb_hops;
if( truncated_hops > SX126X_LR_FHSS_HOP_TABLE_SIZE )
{
truncated_hops = SX126X_LR_FHSS_HOP_TABLE_SIZE;
}
while( state->current_hop < truncated_hops )
{
uint16_t nb_symbols;
// (LR_FHSS_HEADER_BITS + pulse_shape_compensation) symbols on first sync_word, LR_FHSS_HEADER_BITS on
// next sync_words, LR_FHSS_BLOCK_BITS on payload
if( state->current_hop >= params->lr_fhss_params.header_count )
{
if( state->digest.nb_bits > LR_FHSS_BLOCK_BITS )
{
nb_symbols = LR_FHSS_BLOCK_BITS;
}
else
{
nb_symbols = state->digest.nb_bits;
}
}
else if( state->current_hop > 0 )
{
nb_symbols = LR_FHSS_HEADER_BITS;
}
else
{
nb_symbols = LR_FHSS_HEADER_BITS + pulse_shape_compensation;
}
status = sx126x_lr_fhss_write_hop( context, state->current_hop, nb_symbols, state->next_freq_in_pll_steps );
if( status != SX126X_STATUS_OK )
{
return status;
}
state->current_hop++;
state->digest.nb_bits -= nb_symbols;
state->next_freq_in_pll_steps = sx126x_lr_fhss_get_next_freq_in_pll_steps( params, state );
}
}
return status;
}
sx126x_status_t sx126x_lr_fhss_write_payload( const void* context, const sx126x_lr_fhss_state_t* state,
const uint8_t* payload )
{
return sx126x_write_buffer( context, 0x00, payload, state->digest.nb_bytes );
}
sx126x_status_t sx126x_lr_fhss_build_frame( const void* context, const sx126x_lr_fhss_params_t* params,
sx126x_lr_fhss_state_t* state, uint16_t hop_sequence_id,
const uint8_t* payload, uint16_t payload_length,
uint32_t* first_frequency_in_pll_steps )
{
sx126x_status_t status = sx126x_lr_fhss_process_parameters( params, hop_sequence_id, payload_length, state );
if( status != SX126X_STATUS_OK )
{
return status;
}
if( first_frequency_in_pll_steps )
{
*first_frequency_in_pll_steps = state->next_freq_in_pll_steps;
}
uint8_t tx_buffer[LR_FHSS_MAX_PHY_PAYLOAD_BYTES];
lr_fhss_build_frame( &params->lr_fhss_params, state->hop_params.hop_sequence_id, payload, payload_length,
tx_buffer );
status = sx126x_lr_fhss_write_payload( context, state, tx_buffer );
if( status != SX126X_STATUS_OK )
{
return status;
}
status = sx126x_lr_fhss_write_hop_sequence_head( context, params, state );
return status;
}
sx126x_status_t sx126x_lr_fhss_handle_hop( const void* context, const sx126x_lr_fhss_params_t* params,
sx126x_lr_fhss_state_t* state )
{
if( state->current_hop < state->digest.nb_hops )
{
uint16_t nb_bits;
if( state->digest.nb_bits > LR_FHSS_BLOCK_BITS )
{
nb_bits = LR_FHSS_BLOCK_BITS;
}
else
{
nb_bits = state->digest.nb_bits;
}
sx126x_status_t status = sx126x_lr_fhss_write_hop( context, state->current_hop % SX126X_LR_FHSS_HOP_TABLE_SIZE,
LR_FHSS_BLOCK_BITS, state->next_freq_in_pll_steps );
if( status != SX126X_STATUS_OK )
{
return status;
}
state->current_hop++;
state->digest.nb_bits -= nb_bits;
state->next_freq_in_pll_steps = sx126x_lr_fhss_get_next_freq_in_pll_steps( params, state );
}
return SX126X_STATUS_OK;
}
sx126x_status_t sx126x_lr_fhss_handle_tx_done( const void* context, const sx126x_lr_fhss_params_t* params,
sx126x_lr_fhss_state_t* state )
{
const uint8_t ctrl = SX126X_LR_FHSS_DISABLE_HOPPING;
return sx126x_write_register( context, SX126X_LR_FHSS_REG_CTRL, &ctrl, 1 );
}
/*
* -----------------------------------------------------------------------------
* --- PRIVATE FUNCTIONS DEFINITION --------------------------------------------
*/
sx126x_status_t sx126x_lr_fhss_write_hop_config( const void* context, const uint8_t nb_bytes, const uint8_t nb_hops )
{
uint8_t data[] = { SX126X_LR_FHSS_ENABLE_HOPPING, nb_bytes, nb_hops };
return sx126x_write_register( context, SX126X_LR_FHSS_REG_CTRL, data, 3 );
}
sx126x_status_t sx126x_lr_fhss_write_hop( const void* context, const uint8_t index, const uint16_t nb_symbols,
const uint32_t freq_in_pll_steps )
{
if( index >= SX126X_LR_FHSS_HOP_TABLE_SIZE )
{
return SX126X_STATUS_ERROR;
}
uint8_t data[SX126X_LR_FHSS_HOP_ENTRY_SIZE] = {
( uint8_t ) ( nb_symbols >> 8 ), ( uint8_t ) nb_symbols,
( uint8_t ) ( freq_in_pll_steps >> 24 ), ( uint8_t ) ( freq_in_pll_steps >> 16 ),
( uint8_t ) ( freq_in_pll_steps >> 8 ), ( uint8_t ) freq_in_pll_steps,
};
return sx126x_write_register( context, SX126X_LR_FHSS_REG_NUM_SYMBOLS_0 + ( SX126X_LR_FHSS_HOP_ENTRY_SIZE * index ),
data, SX126X_LR_FHSS_HOP_ENTRY_SIZE );
}
uint32_t sx126x_lr_fhss_get_next_freq_in_pll_steps( const sx126x_lr_fhss_params_t* params,
sx126x_lr_fhss_state_t* state )
{
#ifdef HOP_AT_CENTER_FREQ
const int16_t freq_table = 0;
uint32_t grid_offset = 0;
#else
const int16_t freq_table =
lr_fhss_get_next_freq_in_grid( &state->lfsr_state, &state->hop_params, &params->lr_fhss_params );
uint32_t nb_channel_in_grid = params->lr_fhss_params.grid ? 8 : 52;
uint32_t grid_offset = ( 1 + ( state->hop_params.n_grid % 2 ) ) * ( nb_channel_in_grid / 2 );
#endif
unsigned int grid_in_pll_steps = sx126x_lr_fhss_get_grid_in_pll_steps( params );
uint32_t freq = params->center_freq_in_pll_steps - freq_table * grid_in_pll_steps -
( params->device_offset + grid_offset ) * SX126X_LR_FHSS_GRID_INDEX_TO_PLL_STEPS;
#ifndef HOP_AT_CENTER_FREQ
// Perform frequency correction for every other sync header
if( params->lr_fhss_params.enable_hopping && ( state->current_hop < params->lr_fhss_params.header_count ) )
{
if( ( ( ( params->lr_fhss_params.header_count - state->current_hop ) % 2 ) == 0 ) )
{
// OFFSET_SYNCWORD = 488.28125 / 2, and FREQ_STEP_SX1261_2 = 0.95367431640625, so
// OFFSET_SYNCWORD / FREQ_STEP_SX1261_2 = 256
freq = freq + 256;
}
}
#endif
return freq;
}
static inline unsigned int sx126x_lr_fhss_get_grid_in_pll_steps( const sx126x_lr_fhss_params_t* params )
{
return ( params->lr_fhss_params.grid == LR_FHSS_V1_GRID_3906_HZ ) ? SX126X_LR_FHSS_GRID_3906_HZ_PLL_STEPS
: SX126X_LR_FHSS_GRID_25391_HZ_PLL_STEPS;
}
/* --- EOF ------------------------------------------------------------------ */