start with USART (now DEBUG-compile is unavialable)

F0:F030,F042,F072/usbcan_gpio/usart.h

@@ -0,0 +1,48 @@
+/*
+ * This file is part of the usbcangpio project.
+ * Copyright 2026 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>
+
+// DMA linear buffers for Rx/Tx
+#define DMARXBUFSZ      128
+#define DMATXBUFSZ      128
+// incoming ring buffer - only if there's a lot of data in DMA RX buffer
+#define RXRBSZ          256
+
+#define USART_MIN_SPEED 1024
+#define USART_MAX_SPEED 1000000
+
+typedef struct{
+    uint32_t speed;         // baudrate
+    uint8_t No : 2;         // Usart number (1/2)
+    uint8_t Rxen : 1;       // enable rx
+    uint8_t Txen : 1;       // enable tx
+    uint8_t textproto : 1;  // match '\n' and force output by lines (if there's enough place in buffers and monitor == 1)
+    uint8_t monitor : 1;    // async output by incoming (over '\n', IDLE or buffer full)
+} usartconf_t;
+
+int usart_config(usartconf_t *config);
+int usart_start();
+void usart_stop();
+
+int usart_process(uint8_t *buf, int len);
+
+int usart_receive(uint8_t *buf, int len);
+int usart_send(const uint8_t *data, int len);