add spi, not tested yet

F3:F303/CANbus4BTA/encoder.c

@@ -0,0 +1,36 @@
+/*
+ * This file is part of the canbus4bta project.
+ * Copyright 2024 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/>.
+ */
+
+#include "encoder.h"
+#include "flash.h"
+#include "spi.h"
+#include "usart.h"
+
+
+void encoder_setup(){
+    if(FLAG(ENC_IS_SSI)) spi_setup(ENCODER_SPI);
+    else usart_setup();
+}
+
+// read encoder value into buffer `outbuf`
+// return TRUE if all OK
+int read_encoder(uint8_t outbuf[4]){
+    if(!FLAG(ENC_IS_SSI)) return FALSE;
+    *((uint32_t*)outbuf) = 0;
+    return spi_writeread(ENCODER_SPI, outbuf, 4);
+}