1 files changed, 157 insertions, 0 deletions
diff --git a/src/fsm/ubx.c b/src/fsm/ubx.c
new file mode 100644
index 0000000..19c427b
--- /dev/null
+++ b/src/fsm/ubx.c
@@ -0,0 +1,157 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 Matthias P. Braendli
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+*/
+
+#include <stdint.h>
+#include <string.h>
+#include "ubx.h"
+
+static ubx_callbacks_t        ubx_cb;
+
+void ubx_register(const ubx_callbacks_t *cb)
+{
+    memcpy(&ubx_cb, cb, sizeof(ubx_callbacks_t));
+}
+
+static ubx_nav_sol_t     navsol_temp;
+static ubx_nav_timeutc_t navtimeutc_temp;
+static ubx_tim_tm2_t     timtm2_temp;
+
+// State machine variables
+static ubx_state_t ubxState = UBXSTATE_SYNC1;
+static uint16_t msglen;
+static uint8_t* messagedata;
+static uint8_t msgclass;
+static uint8_t msgid;
+static uint8_t cka, ckb;
+
+int ubx_parse(const uint8_t c)
+{
+    switch (ubxState)
+    {
+        case UBXSTATE_SYNC1:
+            if (c == UBX_SYNC1_CHAR) {
+                ubxState = UBXSTATE_SYNC2;
+            }
+            break;
+
+        case UBXSTATE_SYNC2:
+            if (c == UBX_SYNC2_CHAR) {
+                ubxState = UBXSTATE_CLASS;
+            }
+            else if (c == UBX_SYNC1_CHAR) {
+                ubxState = UBXSTATE_SYNC2;
+            }
+            else {
+                ubxState = UBXSTATE_SYNC1;
+            }
+            break;
+
+        case UBXSTATE_CLASS:
+            ubxState = UBXSTATE_ID;
+            msgclass = c;
+
+            // re-init checksum
+            cka = c;
+            ckb = cka;
+            break;
+
+        case UBXSTATE_ID:
+            msgid = c;
+            ubxState = UBXSTATE_LEN1;
+            if (msgclass == UBX_CLASS_NAV) {
+                if (c == UBX_NAV_SOL) {
+                    messagedata = (uint8_t*)&navsol_temp;
+                }
+                else if (c == UBX_NAV_TIMEUTC) {
+                    messagedata = (uint8_t*)&navtimeutc_temp;
+                }
+            }
+            else if (msgclass == UBX_CLASS_TIM && c == UBX_TIM_TM2) {
+                messagedata = (uint8_t*)&timtm2_temp;
+            }
+            else {
+                msgclass = 0;
+                msgid = 0;
+                ubxState = UBXSTATE_SYNC1;
+            }
+            cka += c;
+            ckb += cka;
+            break;
+
+        case UBXSTATE_LEN1:
+            msglen   = (uint16_t)c;
+            ubxState = UBXSTATE_LEN2;
+            cka += c;
+            ckb += cka;
+            break;
+
+        case UBXSTATE_LEN2:
+            msglen  |= ((uint16_t)c) << 8;
+            ubxState = UBXSTATE_DATA;
+            cka += c;
+            ckb += cka;
+            break;
+
+        case UBXSTATE_DATA:
+            cka += c;
+            ckb += cka;
+            if (--msglen) {
+                *(messagedata++) = c;
+            }
+            else {
+                ubxState = UBXSTATE_CKA;
+            }
+            break;
+
+        case UBXSTATE_CKA:
+            if (c == cka) {
+                ubxState = UBXSTATE_CKB;
+            }
+            else {
+                ubxState = UBXSTATE_SYNC1;
+            }
+            break;
+
+        case UBXSTATE_CKB:
+            if (c == ckb) {
+                if (msgclass == UBX_CLASS_NAV) {
+                    if (msgid == UBX_NAV_SOL && ubx_cb.new_ubx_nav_sol) {
+                        ubx_cb.new_ubx_nav_sol(&navsol_temp);
+                    }
+                    else if (msgid == UBX_NAV_TIMEUTC && ubx_cb.new_ubx_nav_timeutc) {
+                        ubx_cb.new_ubx_nav_timeutc(&navtimeutc_temp);
+                    }
+                }
+                else if (msgclass == UBX_CLASS_TIM) {
+                    if (msgid == UBX_TIM_TM2 && ubx_cb.new_ubx_tim_tm2) {
+                        ubx_cb.new_ubx_tim_tm2(&timtm2_temp);
+                    }
+                }
+            }
+
+            ubxState = UBXSTATE_SYNC1;
+    }
+    return ubxState;
+}
+