Initial

src/message.rs

@@ -0,0 +1,57 @@
+use crate::{enums::{FunctionCode, MessageIdentifier}, utils::calculate_checksum};
+
+#[derive(PartialEq, Debug)]
+pub struct Protocol300Message {
+    /// Length of the user data in the telegram
+    pub telegram_length: u8,
+    /// Message Identifier, Request, Response etc.
+    pub message_identifier: MessageIdentifier,
+    /// Function Code, Read Write or RPC
+    pub function_code: FunctionCode,
+    /// Data address, 2 bytes represented as u16
+    pub data_address: u16,
+    /// Expected return bytes (if it is a request) or
+    /// Length of the data to write (if it is a write)
+    pub data_length: u8,
+    /// Return value of the Vitocontrol if it's a read, if it's a write message
+    /// it contains the number ofexpected return bytes
+    pub data: Vec<u8>,
+    /// Checksum
+    pub checksum: u8,
+}
+
+impl Protocol300Message {
+    pub fn new_request_message(data_address: u16, data_length: u8) -> Protocol300Message{
+        let telegram_length: u8 = 5;
+        let message_identifier = MessageIdentifier::Request;
+        let function_code = FunctionCode::VirtualREAD;
+        let data: Vec<u8> = vec![];
+        let checksum = calculate_checksum(telegram_length, message_identifier, function_code, data_address, data_length, &data);
+        Protocol300Message {
+            telegram_length,
+            message_identifier,
+            function_code,
+            data_address,
+            data_length,
+            data: vec![],
+            checksum
+        }
+    }
+
+    pub fn new_write_message(data_address: u16, data: &[u8]) -> Protocol300Message{
+        let data_length: u8 = data.len().try_into().expect("Data too long");
+        let telegram_length: u8 = 5 + data_length;
+        let message_identifier = MessageIdentifier::Request;
+        let function_code = FunctionCode::VirtualWRITE;
+        let checksum = calculate_checksum(telegram_length, message_identifier, function_code, data_address, data_length, data);
+        Protocol300Message {
+            telegram_length,
+            message_identifier,
+            function_code,
+            data_address,
+            data_length,
+            data: data.to_vec(),
+            checksum
+        }
+    }
+}