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diff --git a/boards/base/RaspberryPi/FreeRTOS/uart.c b/boards/base/RaspberryPi/FreeRTOS/uart.c
new file mode 100644
index 00000000..92f837e7
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+++ b/boards/base/RaspberryPi/FreeRTOS/uart.c
@@ -0,0 +1,125 @@
+/* uart.c - UART initialization & communication */
+/* Reference material:
+ * http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
+ * Chapter 13: UART
+ */
+ 
+#include <stdint.h>
+#include <mmio.h>
+#include <uart.h>
+ 
+enum {
+    // The GPIO registers base address.
+    GPIO_BASE = 0x20200000,
+ 
+    // The offsets for reach register.
+ 
+    // Controls actuation of pull up/down to ALL GPIO pins.
+    GPPUD = (GPIO_BASE + 0x94),
+ 
+    // Controls actuation of pull up/down for specific GPIO pin.
+    GPPUDCLK0 = (GPIO_BASE + 0x98),
+ 
+    // The base address for UART.
+    UART0_BASE = 0x20201000,
+ 
+    // The offsets for reach register for the UART.
+    UART0_DR     = (UART0_BASE + 0x00),
+    UART0_RSRECR = (UART0_BASE + 0x04),
+    UART0_FR     = (UART0_BASE + 0x18),
+    UART0_ILPR   = (UART0_BASE + 0x20),
+    UART0_IBRD   = (UART0_BASE + 0x24),
+    UART0_FBRD   = (UART0_BASE + 0x28),
+    UART0_LCRH   = (UART0_BASE + 0x2C),
+    UART0_CR     = (UART0_BASE + 0x30),
+    UART0_IFLS   = (UART0_BASE + 0x34),
+    UART0_IMSC   = (UART0_BASE + 0x38),
+    UART0_RIS    = (UART0_BASE + 0x3C),
+    UART0_MIS    = (UART0_BASE + 0x40),
+    UART0_ICR    = (UART0_BASE + 0x44),
+    UART0_DMACR  = (UART0_BASE + 0x48),
+    UART0_ITCR   = (UART0_BASE + 0x80),
+    UART0_ITIP   = (UART0_BASE + 0x84),
+    UART0_ITOP   = (UART0_BASE + 0x88),
+    UART0_TDR    = (UART0_BASE + 0x8C),
+};
+ 
+/*
+ * delay function
+ * int32_t delay: number of cycles to delay
+ *
+ * This just loops <delay> times in a way that the compiler
+ * wont optimize away.
+ */
+static void delay(int32_t count) {
+    asm volatile("__delay_%=: subs %[count], %[count], #1; bne __delay_%=\n"
+	     : : [count]"r"(count) : "cc");
+}
+ 
+/*
+ * Initialize UART0.
+ */
+void uart_init() {
+    // Disable UART0.
+    mmio_write(UART0_CR, 0x00000000);
+    // Setup the GPIO pin 14 && 15.
+ 
+    // Disable pull up/down for all GPIO pins & delay for 150 cycles.
+    mmio_write(GPPUD, 0x00000000);
+    delay(150);
+ 
+    // Disable pull up/down for pin 14,15 & delay for 150 cycles.
+    mmio_write(GPPUDCLK0, (1 << 14) | (1 << 15));
+    delay(150);
+ 
+    // Write 0 to GPPUDCLK0 to make it take effect.
+    mmio_write(GPPUDCLK0, 0x00000000);
+ 
+    // Clear pending interrupts.
+    mmio_write(UART0_ICR, 0x7FF);
+ 
+    // Set integer & fractional part of baud rate.
+    // Divider = UART_CLOCK/(16 * Baud)
+    // Fraction part register = (Fractional part * 64) + 0.5
+    // UART_CLOCK = 3000000; Baud = 115200.
+ 
+    // Divider = 3000000/(16 * 115200) = 1.627 = ~1.
+    // Fractional part register = (.627 * 64) + 0.5 = 40.6 = ~40.
+    mmio_write(UART0_IBRD, 1);
+    mmio_write(UART0_FBRD, 40);
+ 
+    // Enable FIFO & 8 bit data transmissio (1 stop bit, no parity).
+    mmio_write(UART0_LCRH, (1 << 4) | (1 << 5) | (1 << 6));
+ 
+    // Mask all interrupts.
+    mmio_write(UART0_IMSC, (1 << 1) | (1 << 4) | (1 << 5) |
+		    (1 << 6) | (1 << 7) | (1 << 8) |
+		    (1 << 9) | (1 << 10));
+ 
+    // Enable UART0, receive & transfer part of UART.
+    mmio_write(UART0_CR, (1 << 0) | (1 << 8) | (1 << 9));
+}
+ 
+/*
+ * Transmit a byte via UART0.
+ * uint8_t Byte: byte to send.
+ */
+void uart_putc(uint8_t byte) {
+    // wait for UART to become ready to transmit
+    while (1) {
+        if (!(mmio_read(UART0_FR) & (1 << 5))) {
+	    break;
+	}
+    }
+    mmio_write(UART0_DR, byte);
+}
+ 
+/*
+ * print a string to the UART one character at a time
+ * const char *str: 0-terminated string
+ */
+void uart_puts(const char *str) {
+    while (*str) {
+        uart_putc(*str++);
+    }
+}