example_atten.c

#include "liblinht-ctrl.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static void sweep(void)
{
    printf("\n=== Sweep: 0 -> 31.5 -> 0 dB (0.5 dB steps) ===\n");

    for (int s = 0; s <= 63; s++) {
        double db = s * 0.5;
        printf("[UP] %5.1f dB  (%2d/63)\r", db, s);
        fflush(stdout);
        linht_ctrl_atten_set(1, db);
        linht_ctrl_atten_set(2, db);
        usleep(1000);
    }

    sleep(1);

    for (int s = 63; s >= 0; s--) {
        double db = s * 0.5;
        printf("[DN] %5.1f dB  (%2d/63)\r", db, s);
        fflush(stdout);
        linht_ctrl_atten_set(1, db);
        linht_ctrl_atten_set(2, db);
        usleep(1000);
    }

    sleep(1);
}

static void interactive(void)
{
    printf("\n=== PE4312 Interactive Attenuator Test ===\n");
    printf("  1 <dB>   - set CHIP1  (e.g. 1 10.5)\n");
    printf("  2 <dB>   - set CHIP2  (e.g. 2 0)\n");
    printf("  b <dB>   - set BOTH\n");
    printf("  s <0|1>  - RF switch (0=A, 1=B)\n");
    printf("  sweep    - run sweep\n");
    printf("  q        - quit\n");
    printf("------------------------------------------\n");

    char buf[128];
    while (1) {
        printf("atten> ");
        fflush(stdout);
        if (!fgets(buf, sizeof(buf), stdin)) break;

        size_t n = strlen(buf);
        while (n > 0 && (buf[n-1] == '\n' || buf[n-1] == '\r'))
            buf[--n] = '\0';
        if (n == 0) continue;

        if (buf[0] == 'q' || buf[0] == 'Q') break;

        if (strcmp(buf, "sweep") == 0) { sweep(); continue; }

        char cmd[16];
        double val = 0;
        if (sscanf(buf, "%15s %lf", cmd, &val) < 1) continue;

        if (cmd[0] == '1' && cmd[1] == '\0')
            linht_ctrl_atten_set(1, val);
        else if (cmd[0] == '2' && cmd[1] == '\0')
            linht_ctrl_atten_set(2, val);
        else if (cmd[0] == 'b' && cmd[1] == '\0') {
            linht_ctrl_atten_set(1, val);
            linht_ctrl_atten_set(2, val);
        }
        else if (cmd[0] == 's' && cmd[1] == '\0')
            linht_ctrl_tx_rx_switch_set((bool)val);
        else
            printf("  ? try: 1/2/b <dB>, s <0|1>, sweep, q\n");
    }
}

static void usage(const char *prog)
{
    printf("Usage: %s [options]\n\n", prog);
    printf("Options:\n");
    printf("  -1 <dB>    set CHIP1 attenuation\n");
    printf("  -2 <dB>    set CHIP2 attenuation\n");
    printf("  -b <dB>    set both chips\n");
    printf("  -s <0|1>   RF switch (0=A, 1=B)\n");
    printf("  --sweep    run sweep and exit\n");
    printf("  -h         this help\n");
    printf("\nNo options: interactive mode.\n");
}

int main(int argc, char **argv)
{
    int do_sweep = 0, chip = 0;
    double atten = 0;
    int sw_path = 0;

    for (int i = 1; i < argc; i++) {
        if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0) {
            usage(argv[0]);
            return 0;
        }
        if (strcmp(argv[i], "--sweep") == 0) {
            do_sweep = 1;
            continue;
        }
        if (strcmp(argv[i], "-1") == 0 || strcmp(argv[i], "-2") == 0 ||
            strcmp(argv[i], "-b") == 0) {
            if (++i >= argc) {
                fprintf(stderr, "ERROR: %s requires a value\n", argv[i-1]);
                return 1;
            }
            char *end;
            atten = strtod(argv[i], &end);
            if (end == argv[i] || *end != '\0') {
                fprintf(stderr, "ERROR: bad number '%s'\n", argv[i]);
                return 1;
            }
            chip = (argv[i-1][1] == '1') ? 1 :
                   (argv[i-1][1] == '2') ? 2 : 3;
            continue;
        }
        if (strcmp(argv[i], "-s") == 0) {
            if (++i >= argc) {
                fprintf(stderr, "ERROR: -s requires 0 or 1\n");
                return 1;
            }
            sw_path = atoi(argv[i]);
            if (sw_path != 0 && sw_path != 1) {
                fprintf(stderr, "ERROR: -s must be 0 or 1\n");
                return 1;
            }
            continue;
        }
        fprintf(stderr, "ERROR: unknown option '%s'. Try -h.\n", argv[i]);
        return 1;
    }

    if (linht_ctrl_atten_init() < 0) {
        fprintf(stderr, "ERROR: attenuator init failed\n");
        return 1;
    }

    linht_ctrl_tx_rx_switch_set((bool)sw_path);

    int ret = 0;

    if (do_sweep) {
        sweep();
    } else if (chip) {
        if (chip == 1)      ret = linht_ctrl_atten_set(1, atten);
        else if (chip == 2) ret = linht_ctrl_atten_set(2, atten);
        else                { linht_ctrl_atten_set(1, atten); linht_ctrl_atten_set(2, atten); }
    } else {
        interactive();
    }

    linht_ctrl_atten_cleanup();
    return ret;
}