fixed PCB, add pre-alpha code

F1:F103/Hall_linear/can.h

@@ -0,0 +1,56 @@
+/*
+ * This file is part of the hallinear project.
+ * Copyright 2023 Edward V. Emelianov <edward.emelianoff@gmail.com>.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+
+// CAN bus oscillator frequency: 36MHz
+#define CAN_F_OSC       (36000000UL)
+// timing values TBS1 and TBS2 (in BTR [TBS1-1] and [TBS2-1])
+// use 3 and 2 to get 6MHz
+#define CAN_TBS1    (3)
+#define CAN_TBS2    (2)
+// bitrate oscillator frequency
+#define CAN_BIT_OSC (CAN_F_OSC / (1+CAN_TBS1+CAN_TBS2))
+
+#define CAN_MIN_SPEED   (9600)
+#define CAN_MAX_SPEED   (3000000)
+
+// CAN message
+typedef struct{
+    uint8_t data[8];    // up to 8 bytes of data
+    uint8_t length;     // data length
+    uint16_t ID;        // ID of receiver
+} CAN_message;
+
+typedef enum{
+    CAN_STOP,
+    CAN_READY,
+    CAN_BUSY,
+    CAN_OK,
+    CAN_ERR,
+    CAN_FIFO_OVERRUN
+} CAN_status;
+
+void CAN_setup();
+CAN_status CAN_send(CAN_message *msg);
+void CAN_proc();
+CAN_message *CAN_receive();
+void CAN_reinit();