Adding VCOM GPIO and USART pin exmple for the 32l476disco board

Author: mathk

examples/serial_vcom.rs

@@ -29,21 +29,24 @@ fn main() -> ! {
     let mut rcc = p.RCC.constrain();
     let mut gpioa = p.GPIOA.split(&mut rcc.ahb2);
     // let mut gpiob = p.GPIOB.split(&mut rcc.ahb2);
+    // let mut gpiod = p.GPIOD.split(&mut rcc.ahb2);
 
     // clock configuration using the default settings (all clocks run at 8 MHz)
     let clocks = rcc.cfgr.freeze(&mut flash.acr);
     // TRY this alternate clock configuration (clocks run at nearly the maximum frequency)
     // let clocks = rcc.cfgr.sysclk(64.mhz()).pclk1(32.mhz()).freeze(&mut flash.acr);
 
     let tx = gpioa.pa2.into_af7(&mut gpioa.moder, &mut gpioa.afrl);
-     // let tx = gpiob.pb6.into_af7(&mut gpiob.moder, &mut gpiob.afrl);
+    // let tx = gpiob.pb6.into_af7(&mut gpiob.moder, &mut gpiob.afrl);
+    // let tx = gpiod.pd5.into_af7(&mut gpiod.moder, &mut gpiod.afrl);
 
     let rx = gpioa.pa3.into_af7(&mut gpioa.moder, &mut gpioa.afrl);
-     // let rx = gpiob.pb7.into_af7(&mut gpiob.moder, &mut gpiob.afrl);
+    // let rx = gpiob.pb7.into_af7(&mut gpiob.moder, &mut gpiob.afrl);
+    // let rx = gpiod.pd6.into_af7(&mut gpiod.moder, &mut gpiod.afrl);
 
      // TRY using a different USART peripheral here
-    let serial = Serial::usart2(p.USART2, (tx, rx), 9_600.bps(), clocks, &mut rcc.apb1r1);
-    let (mut tx, _) = serial.split();
+    let serial = Serial::usart2(p.USART2, (tx, rx), 115_200.bps(), clocks, &mut rcc.apb1r1);
+    let (mut tx, mut rx) = serial.split();
 
     let sent = b'X';
 
@@ -58,10 +61,11 @@ fn main() -> ! {
     block!(tx.write(sent)).ok();
     block!(tx.write(sent)).ok();
 
-    // when using virtual com port for recieve, causes a framing error
-    // let received = block!(rx.read()).unwrap();
+    // when using virtual com port for recieve can causes a framing error
+    // On the stm32l476 discovery it is working fine at 115200 baud
+    let received = block!(rx.read()).unwrap();
 
-    // assert_eq!(received, sent);
+    assert_eq!(received, sent);
 
     // if all goes well you should reach this breakpoint
     asm::bkpt();

src/gpio.rs

@@ -589,6 +589,17 @@ gpio!(GPIOB, gpiob, gpiob, gpioben, gpiobrst, PBx, [
     PB7: (pb7, 7, Input<Floating>, AFRL),
 ]);
 
+gpio!(GPIOD, gpiod, gpioc, gpioden, gpiodrst, PDx, [
+    PD0: (pd0, 0, Input<Floating>, AFRL),
+    PD1: (pd1, 1, Input<Floating>, AFRL),
+    PD2: (pd2, 2, Input<Floating>, AFRL),
+    PD3: (pd3, 3, Input<Floating>, AFRL),
+    PD4: (pd4, 4, Input<Floating>, AFRL),
+    PD5: (pd5, 5, Input<Floating>, AFRL),
+    PD6: (pd6, 6, Input<Floating>, AFRL),
+    PD7: (pd7, 7, Input<Floating>, AFRL),
+    PD8: (pd8, 8, Input<Floating>, AFRH),
+]);
 
 gpio!(GPIOE, gpioe, gpioc, gpioeen, gpioerst, PEx, [
     PE0: (pe0, 0, Input<Floating>, AFRL),
@@ -599,5 +610,5 @@ gpio!(GPIOE, gpioe, gpioc, gpioeen, gpioerst, PEx, [
     PE5: (pe5, 5, Input<Floating>, AFRL),
     PE6: (pe6, 6, Input<Floating>, AFRL),
     PE7: (pe7, 7, Input<Floating>, AFRL),
-    PE8: (pe8, 8, Input<Floating>, AFRL),
+    PE8: (pe8, 8, Input<Floating>, AFRH),
 ]);

src/serial.rs

@@ -15,6 +15,7 @@ use crate::stm32::{USART1, USART2};
 use void::Void;
 
 use crate::gpio::gpioa::{PA10, PA2, PA3, PA9};
+use crate::gpio::gpiod::{PD5, PD6};
 use crate::gpio::gpiob::{PB6, PB7};
 use crate::gpio::{AF7, Alternate, Input, Floating};
 use crate::rcc::{APB1R1, APB2, Clocks};
@@ -34,6 +35,8 @@ pub enum Event {
 /// Serial error
 #[derive(Debug)]
 pub enum Error {
+    // Read timeout
+    ReadTimeOut,
     /// Framing error
     Framing,
     /// Noise error
@@ -62,9 +65,9 @@ impl Pins<USART2> for (PA2<Alternate<AF7, Input<Floating>>>, PA3<Alternate<AF7,
     const REMAP: u8 = 0;
 }
 
-// impl Pins<USART2> for (PD5<Alternate<PushPull>>, PD6<Input<Floating>>) {
-//     const REMAP: u8 = 0;
-// }
+impl Pins<USART2> for (PD5<Alternate<AF7, Input<Floating>>>, PD6<Alternate<AF7, Input<Floating>>>) {
+    const REMAP: u8 = 0;
+}
 
 
 /// Serial abstraction
@@ -109,8 +112,8 @@ macro_rules! hal {
 
                     // disable hardware flow control
                     // usart.cr3.write(|w| w.rtse().clear_bit().ctse().clear_bit());
-
                     usart.cr3.write(|w| w.dmat().set_bit().dmar().set_bit()); // enable DMA transfers
+                    //usart.cr3.write(|w| w.onebit().set_bit());
 
                     let brr = clocks.$pclkX().0 / baud_rate.0;
                     assert!(brr >= 16, "impossible baud rate");
@@ -181,7 +184,9 @@ macro_rules! hal {
                     // NOTE(unsafe) atomic read with no side effects
                     let isr = unsafe { (*$USARTX::ptr()).isr.read() };
 
-                    Err(if isr.pe().bit_is_set() {
+                    Err(if isr.rtof().bit_is_set() {
+                        nb::Error::Other(Error::ReadTimeOut)
+                    } else if isr.pe().bit_is_set() {
                         nb::Error::Other(Error::Parity)
                     } else if isr.fe().bit_is_set() {
                         nb::Error::Other(Error::Framing)