uart.h

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#pragma once
 
#include <PropWare/PropWare.h>
#include <PropWare/serial/uart/uartcommondata.h>
 
namespace PropWare {
 
#ifdef __PROPELLER_COG__
#define virtual
#endif
 
class UART {
    public:
        enum class Parity {  NO_PARITY,EVEN_PARITY, ODD_PARITY
        };
 
#define UART_ERRORS_LIMIT            16
 
#define UART_ERRORS_BASE             64
 
        typedef enum {                NO_ERROR      = 0,                             BEG_ERROR = UART_ERRORS_BASE,                             BAUD_TOO_HIGH = BEG_ERROR,                         PARITY_ERROR,    INVALID_DATA_WIDTH,INVALID_STOP_BIT_WIDTH,                          NULL_POINTER,                    TIMEOUT_ERROR,                          END_ERROR     = UART::TIMEOUT_ERROR
        } ErrorCode;
 
    public:
        static const uint8_t DEFAULT_DATA_WIDTH     = 8;
        static const Parity  DEFAULT_PARITY         = Parity::NO_PARITY;
        static const uint8_t DEFAULT_STOP_BIT_WIDTH = 1;
 
        static const int MAX_BAUD = 4413793;
 
    public:
        virtual ErrorCode set_data_width (const uint8_t dataWidth) {
            if (1 > dataWidth || dataWidth > 16)
                return UART::INVALID_DATA_WIDTH;
 
            this->m_dataWidth = dataWidth;
 
            this->m_dataMask = 0;
            for (uint8_t i = 0; i < this->m_dataWidth; ++i)
                this->m_dataMask |= 1 << i;
 
            this->set_parity_mask();
            this->set_total_bits();
 
            return UART::NO_ERROR;
        }
 
        uint8_t get_data_width () const {
            return this->m_dataWidth;
        }
 
        virtual void set_parity (const UART::Parity parity) {
            this->m_parity = parity;
            this->set_parity_mask();
            this->set_stop_bit_mask();
            this->set_total_bits();
        }
 
        UART::Parity get_parity () const {
            return this->m_parity;
        }
 
        ErrorCode set_stop_bit_width (const uint8_t stopBitWidth) {
            // Error checking
            if (0 == stopBitWidth || stopBitWidth > 14)
                return UART::INVALID_STOP_BIT_WIDTH;
 
            this->m_stopBitWidth = stopBitWidth;
 
            this->set_stop_bit_mask();
 
            this->set_total_bits();
 
            return NO_ERROR;
        }
 
        uint8_t get_stop_bit_width () const {
            return this->m_stopBitWidth;
        }
 
        void set_baud_rate (const int32_t baudRate) {
            this->m_bitCycles = CLKFREQ / baudRate;
        }
 
        int32_t get_baud_rate () const {
            return CLKFREQ / this->m_bitCycles;
        }
 
    protected:
        UART () {
            this->set_data_width(UART::DEFAULT_DATA_WIDTH);
            this->set_parity(UART::DEFAULT_PARITY);
            this->set_stop_bit_width(UART::DEFAULT_STOP_BIT_WIDTH);
            this->set_baud_rate(_cfg_baudrate);
        }
 
        void set_stop_bit_mask () {
            // Create the mask to the far right
            this->m_stopBitMask = 1;
            for (uint8_t i      = 0; i < this->m_stopBitWidth - 1; ++i)
                this->m_stopBitMask |= this->m_stopBitMask << 1;
 
            // Shift the mask into position (taking into account the current
            // parity settings)
            this->m_stopBitMask <<= this->m_dataWidth;
            if (Parity::NO_PARITY != this->m_parity)
                this->m_stopBitMask <<= 1;
        }
 
        void set_parity_mask () {
            this->m_parityMask = (uint16_t) (1 << this->m_dataWidth);
        }
 
        void set_total_bits () {
            // Total bits = start + data + parity + stop bits
            this->m_totalBits = (uint8_t) (1 + this->m_dataWidth
                    + this->m_stopBitWidth);
            if (Parity::NO_PARITY != this->m_parity)
                ++this->m_totalBits;
        }
 
    protected:
        uint8_t      m_dataWidth;
        uint16_t     m_dataMask;
        UART::Parity m_parity;
        uint16_t     m_parityMask;
        uint8_t      m_stopBitWidth;
        uint32_t     m_stopBitMask;
        uint32_t     m_bitCycles;
        uint8_t      m_totalBits;
};
 
#ifdef __PROPELLER_COG__
#undef virtual
#endif
 
}