flipperzero-firmware/applications/cc1101-workaround/cc1101-workaround.c

#include "flipper.h"
#include "u8g2.h"
#include <stdio.h>

#include "cc1101/cc1101.h"

#define MIN_DBM -120
#define STEP_DBM 10
#define RSSI_DELAY 600 //rssi delay in micro second

#define RSSI_THRESHOLD -60

#define START_SUB_BAND 3
#define STOP_SUB_BAND 3
#define NUM_OF_SUB_BANDS 7
#define CAL_INT 20 //cal every 10 channels(every 1MHz)

//variables used to calculate rssi
uint8_t rssi_dec;
int16_t rssi_dBm;
uint8_t rssi_offset[NUM_OF_SUB_BANDS] = {74, 74, 74, 74, 74, 74, 74};

#define CHAN_SPA 0.05 //channel spacing

float base_freq[NUM_OF_SUB_BANDS] = {387, 399.8, 412.6, 425.4, 438.2, 451, 463.8};
//FREQ2,FREQ1,FREQ0
uint8_t freqSettings[NUM_OF_SUB_BANDS][3] = {
    {0x0E, 0xE2, 0x76}, //band0
    {0x0F, 0x60, 0x76},
    {0x0F, 0xDE, 0x76}, //band1
    {0x10, 0x5C, 0x76},
    {0x10, 0xDA, 0x76},
    {0x11, 0x58, 0x8F},
    {0x11, 0xD6, 0x8F}}; //band2
//no change in TEST0 WHERE (>430.5MHz) one should change from TEST0=0x0B to 0x09
uint16_t limitTest0Reg[NUM_OF_SUB_BANDS] = {256, 256, 256, 103, 0, 0, 0};
/* setting to use 50khz channel spacing whole band*****************************************/

//int16_t rssiData[NUM_OF_SUB_BANDS][256];
int16_t rssiTable[256];
uint16_t channelNumber[256];
uint8_t carrierSenseCounter = 0; //counter used to keep track on how many CS has been asserted

uint8_t firstChannel[NUM_OF_SUB_BANDS] = {0, 0, 0, 160, 0, 0, 0};
//stop channel in each subband
uint8_t lastChannel[NUM_OF_SUB_BANDS] = {255, 255, 255, 180, 255, 255, 4};
//initialized to a value lower than the rssi threshold/ higher than channel number
int16_t highRSSI[NUM_OF_SUB_BANDS] =
    {MIN_DBM, MIN_DBM, MIN_DBM, MIN_DBM, MIN_DBM, MIN_DBM, MIN_DBM};
uint16_t selectedChannel[NUM_OF_SUB_BANDS] = {300, 300, 300, 300, 300, 300, 300};

int8_t activeBand; //store subband that contains strongest signal
uint16_t activeChannel; //

int16_t calRSSI(uint8_t rssi_dec, uint8_t rssiOffset) {
    int16_t rssi;

    if(rssi_dec >= 128) {
        rssi = (int16_t)((int16_t)(rssi_dec - 256) / 2) - rssiOffset;
    } else {
        rssi = (rssi_dec / 2) - rssiOffset;
    }

    return rssi;
}

void scanFreq(CC1101* cc1101) {
    uint8_t calCounter; //to deterin when to calibrate
    uint8_t subBand;
    uint16_t channel;
    uint16_t i;

    float freq;

    cc1101->SpiWriteReg(CC1101_MCSM0, 0x08); //disalbe FS_AUTOCAL
    cc1101->SpiWriteReg(CC1101_AGCCTRL2, 0x43 | 0x0C); //MAX_DVGA_GAIN to 11 for fast rssi
    cc1101->SpiWriteReg(CC1101_AGCCTRL0, 0xB0); //max AGC WAIT_TIME; 0 filter_length
    cc1101->SetMod(GFSK); //set to GFSK for fast rssi measurement | +8 is dcfilter off

    // 1) loop through all sub bands
    for(subBand = START_SUB_BAND; subBand < STOP_SUB_BAND + 1; subBand++) {
        //1.1) set subBands freq by FREQ2, FREQ1, FREQ0
        cc1101->SetFreq(
            freqSettings[subBand][0], freqSettings[subBand][1], freqSettings[subBand][2]);
        //1.2) set TEST0--maybe!
        //1.3) reset calibration counter
        calCounter = 0;
        // 1.4) loop throuhg all channels
        for(channel = firstChannel[subBand]; channel <= lastChannel[subBand]; channel++) {
            uint8_t pktStatus;
            //1.4.1) set channel register
            cc1101->SetChannel(channel);

            //1.4.2)  set TEST0
            if(channel == limitTest0Reg[subBand]) {
                //set test0 to 0x09
                cc1101->SpiWriteReg(CC1101_TEST0, 0x09);
                //set FSCAL2 to 0x2A to force VCO HIGH
                cc1101->SpiWriteReg(CC1101_FSCAL2, 0x2A);
                //clear calCounter to invoke mannual calibration
                calCounter = 0;
            }
            //1.4.3) calibrate every 1MHz
            if(calCounter++ == 0) {
                //perform a manual calibration by issuing SCAL command
                cc1101->SpiStrobe(CC1101_SCAL);
            }
            //1.4.4) reset calCounter when 1MHz reached
            if(calCounter == CAL_INT) {
                calCounter = 0;
            }
            // 1.4.5-6 enter rx mode
            cc1101->SetReceive();
            //1.4.7 wait for RSSI to be valid: less than 1.5ms
            delayMicroseconds(RSSI_DELAY);
            // 1.4.8) read PKTSTATUS register while the radio is in RX state
            pktStatus = cc1101->SpiReadStatus(CC1101_PKTSTATUS);
            // 1.4.9) enter IDLE state by issuing a SIDLE command
            cc1101->SpiStrobe(CC1101_SIDLE);
            // 1.4.10) check if CS is assearted
            // //read rssi value and converto to dBm form
            rssi_dec = (uint8_t)cc1101->SpiReadStatus(CC1101_RSSI);
            rssi_dBm = calRSSI(rssi_dec, rssi_offset[subBand]);

            //rssiData[subBand][channel]=rssi_dBm;
            if(pktStatus & 0x40) { //CS assearted
                //store rssi value and corresponding channel number
                rssiTable[carrierSenseCounter] = rssi_dBm;
                channelNumber[carrierSenseCounter] = channel;
                carrierSenseCounter++;
            }

#ifdef CC1101_DEBUG
            printf("rssi_dBm: %d\n", rssi_dBm);
#endif
        } //end channel lop

        //1.5)before moving to next sub band, scan through rssiTable to find highest rssi value
        for(i = 0; i < carrierSenseCounter; i++) {
            if(rssiTable[i] > highRSSI[subBand]) {
                highRSSI[subBand] = rssiTable[i];
                selectedChannel[subBand] = channelNumber[i];
            }
        }
        // Serial.print("subBand:------------------>");
        // Serial.println(subBand);
        // Serial.print("selectedChannel:");
        // Serial.println(selectedChannel[subBand]);
        // Serial.print("highRSSI:");
        // Serial.println(highRSSI[subBand]);

        //1.6) reset carrierSenseCounter
        carrierSenseCounter = 0;
    } // end band loop

    //2) when all sub bands has been scanned , find best subband and channel
    int16_t tempRssi = MIN_DBM;
    for(subBand = 0; subBand < NUM_OF_SUB_BANDS; subBand++) {
        if(highRSSI[subBand] > tempRssi) {
            tempRssi = highRSSI[subBand];
            activeChannel = selectedChannel[subBand];
            activeBand = subBand;
        }
    }

    // printf("activeBand:**********> %d, activeChannel %d,\n", activeBand, activeChannel);

    cc1101->SpiWriteReg(CC1101_MCSM0, 0x18); //enable FS_AUTOCAL
    cc1101->SpiWriteReg(CC1101_AGCCTRL2, 0x43); //back to recommended config
    cc1101->SpiWriteReg(CC1101_AGCCTRL0, 0x91); //back to recommended config
}

void jamming(CC1101* cc1101, uint8_t band, uint16_t channel, uint16_t miniSec) {
    cc1101->SetFreq(freqSettings[band][0], freqSettings[band][1], freqSettings[band][2]);
    cc1101->SetChannel(channel);
    // digitalWrite(19,0);
    cc1101->SetTransmit();
    delay(miniSec);

    cc1101->SpiStrobe(CC1101_SIDLE);
}

extern QueueHandle_t event_queue;

bool jamm_on = false;

void set_jam(bool state) {
    jamm_on = state;
}

extern "C" void radio() {
    CC1101 cc1101(SS_PIN, GDO0, GDO2);

    uint8_t address = cc1101.Init();

    if(address > 0) {
        printf("CC1101 init done: %d\n", address);
    } else {
        printf("CC1101 init fail\n");
    }

    /* setting to use 50khz channel spacing**************************************/
    cc1101.SpiWriteReg(
        CC1101_MDMCFG4, 0xCD); // RX filter bandwidth 58.035714(0xFD) 100k(0xCD) 200k(0x8D)
    cc1101.SpiWriteReg(
        CC1101_MDMCFG3, 0x3B); //datarate config 250kBaud  for the purpose of fast rssi measurement
    cc1101.SpiWriteReg(CC1101_MDMCFG1, 0x20); //FEC preamble etc. last 2 bits for channel spacing
    cc1101.SpiWriteReg(CC1101_MDMCFG0, 0xF8); //50khz channel spacing

    Event event;
    event.type = EventTypeRadio;

    while(1) {
        for(uint8_t i = 0; i <= NUM_OF_SUB_BANDS; i++) {
            highRSSI[i] = MIN_DBM;
        }

        activeChannel = 300;

        scanFreq(&cc1101);

        if(activeChannel < 256 && highRSSI[activeBand] > RSSI_THRESHOLD) {
            float freq = base_freq[activeBand] + CHAN_SPA * activeChannel;

            /*
            printf(
                "channel: %d, freq: %d, RSSI: %d\n",
                activeChannel,
                (uint32_t)(freq * 1000),
                highRSSI[activeBand]
            );
            */

            event.value.radio.freq = freq;
            event.value.radio.rssi_db = highRSSI[activeBand];
            xQueueSend(event_queue, (void*)&event, 0);

            if(jamm_on) {
                jamming(&cc1101, activeBand, activeChannel, 500);
            } else {
                osDelay(1000);
            }
        } else {
            // printf("0 carrier sensed\n");
        }

        osDelay(1);
    }
}

void cc1101_workaround(void* p) {
    FuriRecordSubscriber* fb_record =
        furi_open_deprecated("u8g2_fb", false, false, NULL, NULL, NULL);

    if(fb_record == NULL) {
        printf("[cc1101] cannot create fb record\n");
        furiac_exit(NULL);
    }

    while(1) {
        u8g2_t* fb = furi_take(fb_record);
        if(fb != NULL) {
            u8g2_SetFont(fb, u8g2_font_6x10_mf);
            u8g2_SetDrawColor(fb, 1);
            u8g2_SetFontMode(fb, 1);
            u8g2_DrawStr(fb, 2, 12, "cc1101 workaround");
        }
        furi_commit(fb_record);

        delay(1000);
    }
}