src/Usart.h

   1 #ifndef AVR_USART_H
   2 #define AVR_USART_H
   3
   4 #include "Hardware.h"
   5 #include <string>
   6
   7 namespace avr {
   8
   9         class Usart : public avr::Hardware {
  10                 public:
  11                         Usart(Bus & bus, const std::string & name, unsigned int udreVec,
  12                                         unsigned int rxVec, unsigned int txVec);
  13                         ~Usart();
  14
  15                 public:
  16                         /**
  17                          * Attach a register with name \e name to the hardware.
  18                          */
  19                         bool attachReg(const char *name, IORegister *reg);
  20
  21                         /**
  22                          * Finishes the construction of the hardware.
  23                          * This should verify the registers and parameters
  24                          * @returns true if build was successful.
  25                          */
  26                         bool finishBuild();
  27
  28                         /**
  29                          * An attached register changed state.
  30                          */
  31                         void regChanged( IORegister *reg );
  32
  33                         /**
  34                          * Perform a single step.
  35                          */
  36                         void step();
  37
  38                         /**
  39                          * Reset the internal hardware.
  40                          */
  41                         void reset();
  42
  43                         /**
  44                          * Called just before an interrupt handler is invoked.
  45                          */
  46                         void beforeInvokeInterrupt(unsigned int vector);
  47
  48                 private:
  49                         void receiveCycle();
  50                         void transmitCycle();
  51                         void checkForNewSetIrq(unsigned char val);
  52                         void checkForNewClearIrq(unsigned char val);
  53                         void setUdr(unsigned char udr);
  54                         void setUcsra(unsigned char ucsra);
  55                         void setUcsrb(unsigned char ucsrb);
  56                         void setFramelength();
  57
  58                 private:
  59                         IORegister *udr;
  60                         IORegister *ucsra;
  61                         IORegister *ucsrb;
  62                         IORegister *ubrrl;
  63                         IORegister *ubrrh;
  64
  65                 private:
  66                         std::string name;
  67                         unsigned int udreVec;
  68                         unsigned int rxVec;
  69                         unsigned int txVec;
  70
  71                         unsigned char udrWrite;
  72                         unsigned char udrRead;
  73                         int baudRate;
  74                         int frameLength;
  75
  76                         enum {
  77                                 TX_STARTBIT,
  78                                 TX_DATABIT,
  79                                 TX_PARITY,
  80                                 TX_STOPBIT,
  81                                 TX_STOPBIT2,
  82                                 TX_COMPLETE,
  83                                 TX_FINISHED
  84                         } txState;
  85                         int txShift;
  86                         int txBitCount;
  87                         int txRate;
  88
  89                         enum {
  90                                 RX_STARTBIT,
  91                                 RX_DATABIT,
  92                                 RX_PARITY,
  93                                 RX_STOPBIT,
  94                                 RX_STOPBIT2,
  95                                 RX_FINISHED
  96                         } rxState;
  97                         int rxShift;
  98                         int rxBitCount;
  99                         int rxSample;
 100
 101                         unsigned char ucsra_old;
 102                         unsigned char ucsrb_old;
 103                         unsigned char ucsrc;
 104         };
 105
 106 }
 107
 108 #endif /*AVR_USART_H*/