remove dependence of libusefull_macros

LibSidServo/serial.h

@@ -18,11 +18,19 @@
 
 #pragma once
 
+#include "sidservo.h"
+
 // magick starting sequence
 #define ENC_MAGICK  (204)
 // encoder data sequence length
 #define ENC_DATALEN (13)
+// max error counter (when read() returns -1)
+#define MAX_ERR_CTR (100)
+// encoder ticks per turn
+#define ENC_TURN_XTICKS     (111111.)
+#define ENC_TURN_YTICKS     (111111.)
 
 int openEncoder(const char *path, int speed);
 int openMount(const char *path, int speed);
 void closeSerial();
+mcc_errcodes_t getEnc(coords_t *c);