v1.0.0

* Initial release for SX1302 CoreCell Reference Design.

tools/payload_tools/payload_crc.c

@@ -0,0 +1,110 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+
+/* -------------------------------------------------------------------------- */
+/* --- SUBFUNCTIONS DECLARATION --------------------------------------------- */
+
+static void usage(void);
+uint16_t sx1302_lora_payload_crc(const uint8_t * data, uint8_t size);
+void remove_spaces(char *str);
+
+/* -------------------------------------------------------------------------- */
+/* --- MAIN FUNCTION -------------------------------------------------------- */
+
+int main(int argc, char ** argv)
+{
+    int j;
+    uint8_t payload[255];
+    uint8_t payload_size;
+    uint16_t crc;
+    char hexstr[1024];
+
+    if (argc < 2) {
+        usage();
+        return -1;
+    }
+
+    /* Get payload hex string from command line */
+    memcpy(hexstr, argv[1], strlen(argv[1]));
+    hexstr[strlen(argv[1])] = '\0';
+    printf("Input hex string: %s\n", hexstr);
+
+    /* Remove spaces from the string if any */
+    remove_spaces(hexstr);
+    hexstr[strlen(hexstr)] = '\0';
+    printf("Removing spaces: %s\n", hexstr);
+
+    /* Convert hex string to byte array */
+    payload_size = strlen(hexstr) / 2;
+    for (j = 0; j < payload_size; j++) {
+        sscanf(hexstr + 2*j, "%02hhx", &payload[j]);
+    }
+
+    /* Compute CRC */
+    crc = sx1302_lora_payload_crc(payload, payload_size);
+    printf("Payload CRC_16: %04X\n", crc);
+
+    return 0;
+}
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+void usage(void) {
+    printf("Missing payload hex string\n");
+}
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+void remove_spaces(char *str)
+{
+    /* To keep track of non-space character count */
+    int count = 0;
+
+    /* Traverse the given string. If current character
+        is not space, then place it at index 'count++' */
+    for (int i = 0; str[i]; i++) {
+        if (str[i] != ' ') {
+            str[count++] = str[i]; /* here count is incremented */
+        }
+    }
+    str[count] = '\0';
+}
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+void lora_crc16(const char data, int *crc) {
+    int next = 0;
+    next  =  (((data>>0)&1) ^ ((*crc>>12)&1) ^ ((*crc>> 8)&1)                 )      ;
+    next += ((((data>>1)&1) ^ ((*crc>>13)&1) ^ ((*crc>> 9)&1)                 )<<1 ) ;
+    next += ((((data>>2)&1) ^ ((*crc>>14)&1) ^ ((*crc>>10)&1)                 )<<2 ) ;
+    next += ((((data>>3)&1) ^ ((*crc>>15)&1) ^ ((*crc>>11)&1)                 )<<3 ) ;
+    next += ((((data>>4)&1) ^ ((*crc>>12)&1)                                  )<<4 ) ;
+    next += ((((data>>5)&1) ^ ((*crc>>13)&1) ^ ((*crc>>12)&1) ^ ((*crc>> 8)&1))<<5 ) ;
+    next += ((((data>>6)&1) ^ ((*crc>>14)&1) ^ ((*crc>>13)&1) ^ ((*crc>> 9)&1))<<6 ) ;
+    next += ((((data>>7)&1) ^ ((*crc>>15)&1) ^ ((*crc>>14)&1) ^ ((*crc>>10)&1))<<7 ) ;
+    next += ((((*crc>>0)&1) ^ ((*crc>>15)&1) ^ ((*crc>>11)&1)                 )<<8 ) ;
+    next += ((((*crc>>1)&1) ^ ((*crc>>12)&1)                                  )<<9 ) ;
+    next += ((((*crc>>2)&1) ^ ((*crc>>13)&1)                                  )<<10) ;
+    next += ((((*crc>>3)&1) ^ ((*crc>>14)&1)                                  )<<11) ;
+    next += ((((*crc>>4)&1) ^ ((*crc>>15)&1) ^ ((*crc>>12)&1) ^ ((*crc>> 8)&1))<<12) ;
+    next += ((((*crc>>5)&1) ^ ((*crc>>13)&1) ^ ((*crc>> 9)&1)                 )<<13) ;
+    next += ((((*crc>>6)&1) ^ ((*crc>>14)&1) ^ ((*crc>>10)&1)                 )<<14) ;
+    next += ((((*crc>>7)&1) ^ ((*crc>>15)&1) ^ ((*crc>>11)&1)                 )<<15) ;
+    (*crc) = next;
+}
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
+
+uint16_t sx1302_lora_payload_crc(const uint8_t * data, uint8_t size) {
+    int i;
+    int crc = 0;
+
+    for (i = 0; i < size; i++) {
+        lora_crc16(data[i], &crc);
+    }
+
+    //printf("CRC16: 0x%02X 0x%02X (%X)\n", (uint8_t)(crc >> 8), (uint8_t)crc, crc);
+    return (uint16_t)crc;
+}