a7105_listen.tc

a7105_listen.tc — background FIFO RX. EveryLoop drains FIFO when packets

Source on GitHub

// a7105_listen.tc — background FIFO RX. EveryLoop drains FIFO when packets
// arrive, frames are addLog'd as they come. Commands are zero-work — they
// just toggle state, so no instruction-limit / vm_mutex issues.
//
// Commands:
//   GO <ch>  -> tune to channel, start listening
//   GO       -> same channel as before
//   OFF      -> stop listening
//   ST       -> show stats

#define CS_PIN  3
#define SLOT    2
#define A7_STB_IDLE 0x90
#define A7_STB_PLL  0xB0
#define A7_STB_RX   0xC0
#define A7_STB_RST_RDPTR 0xE0

char spi[20];
int  cur_ch = 31;
int  active = 0;
int  grabs  = 0;

void a7_strobe(int s) {
    spi[0] = s & 0xFF;
    spiTransfer(SLOT, spi, 1, 1);
}

void a7_write(int addr, int val) {
    spi[0] = addr & 0x3F;
    spi[1] = val & 0xFF;
    spiTransfer(SLOT, spi, 2, 1);
}

int a7_read(int addr) {
    spi[0] = 0x40 | (addr & 0x3F);
    spi[1] = 0x00;
    spiTransfer(SLOT, spi, 2, 1);
    return spi[1] & 0xFF;
}

void a7_reset() {
    a7_write(0x00, 0x00);
    delay(10);
}

void a7_init() {
    a7_reset();
    a7_write(0x01, 0x62);
    a7_write(0x03, 0x0F);
    a7_write(0x0D, 0x05);
    a7_write(0x0E, 0x00);
    a7_write(0x10, 0x9E);
    a7_write(0x11, 0x4B);
    a7_write(0x12, 0x00);
    a7_write(0x13, 0x02);
    a7_write(0x14, 0x16);
    a7_write(0x15, 0x2B);
    a7_write(0x16, 0x12);
    a7_write(0x17, 0x4A);
    a7_write(0x18, 0x62);
    a7_write(0x19, 0x80);
    a7_write(0x1C, 0x0A);
    a7_write(0x1E, 0x32);
    a7_write(0x06, 0xAA);
    a7_write(0x06, 0xAA);
    a7_write(0x06, 0xAA);
    a7_write(0x06, 0xAA);
    a7_write(0x1F, 0x07);
    a7_write(0x20, 0x1F);
}

void a7_rx_on(int ch) {
    a7_strobe(A7_STB_IDLE);
    delay(1);
    a7_write(0x0F, ch & 0xFF);
    a7_strobe(A7_STB_PLL);
    delay(1);
    a7_strobe(A7_STB_RST_RDPTR);
    a7_strobe(A7_STB_RX);
    cur_ch = ch;
}

void EveryLoop() {
    if (active == 0) return;
    int m = a7_read(0x00);
    // TRER bit 0: when 0, RX completed (chip auto-back to PLL state)
    if ((m & 0x01) != 0) return;
    // Packet ready — grab it
    char pkt[16];
    a7_strobe(A7_STB_RST_RDPTR);
    int i = 0;
    while (i < 16) {
        spi[0] = 0x40 | 0x05;
        spi[1] = 0x00;
        spiTransfer(SLOT, spi, 2, 1);
        pkt[i] = spi[1] & 0xFF;
        i = i + 1;
    }
    int crcf = (m >> 5) & 1;
    char hex[120];
    sprintf(hex, "FRAME #%d ch=%d crcf=%d  %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X",
        grabs + 1, cur_ch, crcf,
        pkt[0] & 0xFF, pkt[1] & 0xFF, pkt[2] & 0xFF, pkt[3] & 0xFF,
        pkt[4] & 0xFF, pkt[5] & 0xFF, pkt[6] & 0xFF, pkt[7] & 0xFF,
        pkt[8] & 0xFF, pkt[9] & 0xFF, pkt[10] & 0xFF, pkt[11] & 0xFF,
        pkt[12] & 0xFF, pkt[13] & 0xFF, pkt[14] & 0xFF, pkt[15] & 0xFF);
    addLog(hex);
    grabs = grabs + 1;
    // re-arm RX
    a7_strobe(A7_STB_RX);
}

void Command(char cmd[]) {
    char buf[80];
    if (strFind(cmd, "OFF") >= 0) {
        active = 0;
        a7_strobe(A7_STB_IDLE);
        sprintf(buf, "LSN off. total frames=%d", grabs);
        responseCmnd(buf);
    } else if (strFind(cmd, "ST") >= 0) {
        sprintf(buf, "active=%d ch=%d frames=%d", active, cur_ch, grabs);
        responseCmnd(buf);
    } else {
        // GO [ch]
        char arg[8];
        strSub(arg, cmd, 3, 0);
        int ch = atoi(arg);
        if (ch < 0 || ch > 127) ch = cur_ch;
        a7_init();
        a7_rx_on(ch);
        grabs = 0;
        active = 1;
        sprintf(buf, "LSN on ch=%d  (press remote now)", ch);
        responseCmnd(buf);
    }
}

int main() {
    spiInit(-1, -1, -1, 1);
    spiSetCS(SLOT, CS_PIN);
    delay(50);
    a7_init();
    addCommand("LSN");
    addLog("a7105_listen: LSN GO 31 = start, LSN OFF = stop, LSN ST = stats");
    return 0;
}