From 912098d5b84a0c73d7743c815c6c469a134af99b Mon Sep 17 00:00:00 2001
From: rogerclarkmelbourne <roger@ecbtechnology.com>
Date: Sun, 31 May 2015 18:06:19 +1000
Subject: [PATCH] Updated with commits that had been applied to
 Leaflabs:libmaple since the original copy of the repo was taken (by BobC) in
 Nov 2014

---
 STM32F1/cores/maple/usb_serial.cpp      |  8 ++++++++
 STM32F1/system/libmaple/dma_private.h   |  3 ++-
 STM32F1/system/libmaple/usart_private.h | 17 ++++++++++++-----
 3 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/STM32F1/cores/maple/usb_serial.cpp b/STM32F1/cores/maple/usb_serial.cpp
index c11fd15..fcc39b1 100644
--- a/STM32F1/cores/maple/usb_serial.cpp
+++ b/STM32F1/cores/maple/usb_serial.cpp
@@ -72,9 +72,17 @@ void USBSerial::begin(void) {
 //Roger Clark. Two new begin functions has been added so that normal Arduino Sketches that use Serial.begin(xxx) will compile.
 void USBSerial::begin(unsigned long ignoreBaud) 
 {
+volatile unsigned long removeCompilerWarningsIgnoreBaud=ignoreBaud;
+
+	ignoreBaud=removeCompilerWarningsIgnoreBaud;
 }
 void USBSerial::begin(unsigned long ignoreBaud, uint8_t ignore)
 {
+volatile unsigned long removeCompilerWarningsIgnoreBaud=ignoreBaud;
+volatile uint8_t removeCompilerWarningsIgnore=ignore;
+
+	ignoreBaud=removeCompilerWarningsIgnoreBaud;
+	ignore=removeCompilerWarningsIgnore;
 }
 
 void USBSerial::end(void) {
diff --git a/STM32F1/system/libmaple/dma_private.h b/STM32F1/system/libmaple/dma_private.h
index 82f5fc1..c0ee11f 100644
--- a/STM32F1/system/libmaple/dma_private.h
+++ b/STM32F1/system/libmaple/dma_private.h
@@ -38,10 +38,11 @@
  * in the series support files, which need dma_irq_handler().) */
 #ifdef DMA_GET_HANDLER
 static __always_inline void dma_irq_handler(dma_dev *dev, dma_tube tube) {
-    dma_clear_isr_bits(dev, tube); /* in case handler doesn't */
+
     void (*handler)(void) = DMA_GET_HANDLER(dev, tube);
     if (handler) {
         handler();
+	    dma_clear_isr_bits(dev, tube); /* in case handler doesn't */
     }
 }
 #endif
diff --git a/STM32F1/system/libmaple/usart_private.h b/STM32F1/system/libmaple/usart_private.h
index 8e8e11b..9bc0527 100644
--- a/STM32F1/system/libmaple/usart_private.h
+++ b/STM32F1/system/libmaple/usart_private.h
@@ -38,14 +38,21 @@
 #include <libmaple/usart.h>
 
 static __always_inline void usart_irq(ring_buffer *rb, usart_reg_map *regs) {
+    /* We can get RXNE and ORE interrupts here. Only RXNE signifies
+     * availability of a byte in DR.
+     *
+     * See table 198 (sec 27.4, p809) in STM document RM0008 rev 15.
+     * We enable RXNEIE. */
+    if (regs->SR & USART_SR_RXNE) {
 #ifdef USART_SAFE_INSERT
-    /* If the buffer is full and the user defines USART_SAFE_INSERT,
-     * ignore new bytes. */
-    rb_safe_insert(rb, (uint8)regs->DR);
+        /* If the buffer is full and the user defines USART_SAFE_INSERT,
+         * ignore new bytes. */
+        rb_safe_insert(rb, (uint8)regs->DR);
 #else
-    /* By default, push bytes around in the ring buffer. */
-    rb_push_insert(rb, (uint8)regs->DR);
+        /* By default, push bytes around in the ring buffer. */
+        rb_push_insert(rb, (uint8)regs->DR);
 #endif
+    }
 }
 
 uint32 _usart_clock_freq(usart_dev *dev);