Initial commit

src/rn4020/mod.rs

@@ -0,0 +1,110 @@
+use core::fmt::Write;
+use hal::{
+    clock::Sercom0CoreClock,
+    sercom::{RxpoTxpo, UART0Padout, UART0},
+    target_device::{NVIC, PM, SERCOM0},
+    time::Hertz,
+    //prelude::_embedded_hal_serial_Read as Read,
+    //prelude::_embedded_hal_serial_Write as WriteHal,
+};
+
+#[derive(Clone, Copy)]
+pub enum BaudRate {
+    BR2400,
+    BR9600,
+    BR19200,
+    BR38400,
+    BR115200,
+    BR230400,
+    BR460800,
+    BR921600,
+}
+
+impl Into<Hertz> for BaudRate {
+    fn into(self) -> Hertz {
+        match self {
+            BaudRate::BR2400 => Hertz(2400),
+            BaudRate::BR9600 => Hertz(9600),
+            BaudRate::BR19200 => Hertz(19200),
+            BaudRate::BR38400 => Hertz(38400),
+            BaudRate::BR115200 => Hertz(115200),
+            BaudRate::BR230400 => Hertz(230400),
+            BaudRate::BR460800 => Hertz(460800),
+            BaudRate::BR921600 => Hertz(921600),
+        }
+    }
+}
+
+pub struct RN4020<RX, TX> {
+    /// The reader/writer to the RN4020
+    link: UART0<RX, TX, (), ()>,
+}
+
+impl<RX, TX> RN4020<RX, TX> {
+    /// Create a new
+    pub fn new<T>(
+        clock: &Sercom0CoreClock,
+        baud_rate: BaudRate,
+        sercom: SERCOM0,
+        nvic: &mut NVIC,
+        pm: &mut PM,
+        padout: T,
+    ) -> Self
+    where
+        T: Into<UART0Padout<RX, TX, (), ()>>,
+        UART0Padout<RX, TX, (), ()>: RxpoTxpo,
+    {
+        let mut bl = RN4020 {
+            link: UART0::new(clock, baud_rate, sercom, nvic, pm, padout),
+        };
+        bl.set_baud_rate(baud_rate).unwrap();
+        bl
+    }
+
+    /// This command sets the serialized Bluetooth-friendly name of the device.
+    ///
+    /// `name` is up to 15 alphanumeric characters.
+    /// This command automatically appends the last 2 bytes of the Bluetooth MAC
+    /// address to the name, which is useful for generating a custom name
+    /// with unique numbering.
+    ///
+    /// Will panic if provided with an invalid string.
+    pub fn set_serialized_name(&mut self, name: &str) -> Result<(), ()> {
+        assert!(name.len() <= 15);
+        assert!(name.is_ascii());
+
+        self.link.write_str("S-,").map_err(|_| ())?;
+
+        for c in name.chars() {
+            assert!(c.is_alphanumeric());
+            self.link.write_char(c).map_err(|_| ())?;
+        }
+
+        self.link.write_char('\n').map_err(|_| ())?;
+
+        Ok(())
+    }
+
+    /// This command sets the baud rate of the UART communication.
+    fn set_baud_rate(&mut self, rate: BaudRate) -> Result<(), ()> {
+        // The input parameter is a single digit number in the range of 0 to 7,
+        // representing a baud rate from 2400 to 921K, as shown in Table 2 - 5.
+        // When the baud rate is set to 2400, there is no need to wake the
+        // RN4020 module by pulling WAKE_SW high for UART communication.
+
+        // TODO: Figure out how to change UART settings and make this method public
+
+        let cmd = match rate {
+            BaudRate::BR2400 => "SB,0\n",
+            BaudRate::BR9600 => "SB,1\n",
+            BaudRate::BR19200 => "SB,2\n",
+            BaudRate::BR38400 => "SB,3\n",
+            BaudRate::BR115200 => "SB,4\n",
+            BaudRate::BR230400 => "SB,5\n",
+            BaudRate::BR460800 => "SB,6\n",
+            BaudRate::BR921600 => "SB,7\n",
+        };
+        self.link.write_str(cmd).map_err(|_| ())?;
+        Ok(())
+    }
+}