bdmcf.c

bdm源代码. coldfire处理器用

      bset  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT
    #endif
    #ifdef DEBUG
      lda   #(BDMCF_IDLE*2)  /* reload idle value into A */
    #else
      lda   #(BDMCF_IDLE/2)
    #endif      
    lslx    		  /* shift MSB into C */
    #ifdef DEBUG
      rora        /* rotate C into A */
    #else
			rola
    #endif      
    lsrx          /* shift X back to what it was */
    sta     PTA   /* create falling edge on DSCLK and write the next bit value to the port */  
    lsr     PTC   /* shift the input data bit (PTC0) into C */
		rolx          /* shift the sample into X from the bottom */
     /* transmit and receive bit 4 */
    #ifdef INVERT
      bclr  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT  /* create rising edge on DSCLK */
    #else
      bset  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT
    #endif
    #ifdef DEBUG
      lda   #(BDMCF_IDLE*2)  /* reload idle value into A */
    #else
      lda   #(BDMCF_IDLE/2)
    #endif      
    lslx    		  /* shift MSB into C */
    #ifdef DEBUG
      rora        /* rotate C into A */
    #else
			rola
    #endif      
    lsrx          /* shift X back to what it was */
    sta     PTA   /* create falling edge on DSCLK and write the next bit value to the port */  
    lsr     PTC   /* shift the input data bit (PTC0) into C */
		rolx          /* shift the sample into X from the bottom */
     /* transmit and receive bit 3 */
    #ifdef INVERT
      bclr  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT  /* create rising edge on DSCLK */
    #else
      bset  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT
    #endif
    #ifdef DEBUG
      lda   #(BDMCF_IDLE*2)  /* reload idle value into A */
    #else
      lda   #(BDMCF_IDLE/2)
    #endif      
    lslx    		  /* shift MSB into C */
    #ifdef DEBUG
      rora        /* rotate C into A */
    #else
			rola
    #endif      
    lsrx          /* shift X back to what it was */
    sta     PTA   /* create falling edge on DSCLK and write the next bit value to the port */  
    lsr     PTC   /* shift the input data bit (PTC0) into C */
		rolx          /* shift the sample into X from the bottom */
     /* transmit and receive bit 2 */
    #ifdef INVERT
      bclr  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT  /* create rising edge on DSCLK */
    #else
      bset  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT
    #endif
    #ifdef DEBUG
      lda   #(BDMCF_IDLE*2)  /* reload idle value into A */
    #else
      lda   #(BDMCF_IDLE/2)
    #endif      
    lslx    		  /* shift MSB into C */
    #ifdef DEBUG
      rora        /* rotate C into A */
    #else
			rola
    #endif      
    lsrx          /* shift X back to what it was */
    sta     PTA   /* create falling edge on DSCLK and write the next bit value to the port */  
    lsr     PTC   /* shift the input data bit (PTC0) into C */
		rolx          /* shift the sample into X from the bottom */
     /* transmit and receive bit 1 */
    #ifdef INVERT
      bclr  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT  /* create rising edge on DSCLK */
    #else
      bset  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT
    #endif
    #ifdef DEBUG
      lda   #(BDMCF_IDLE*2)  /* reload idle value into A */
    #else
      lda   #(BDMCF_IDLE/2)
    #endif      
    lslx    		  /* shift MSB into C */
    #ifdef DEBUG
      rora        /* rotate C into A */
    #else
			rola
    #endif      
    lsrx          /* shift X back to what it was */
    sta     PTA   /* create falling edge on DSCLK and write the next bit value to the port */  
    lsr     PTC   /* shift the input data bit (PTC0) into C */
		rolx          /* shift the sample into X from the bottom */
     /* transmit and receive bit 0 */
    #ifdef INVERT
      bclr  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT  /* create rising edge on DSCLK */
    #else
      bset  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT
    #endif
    #ifdef DEBUG
      lda   #(BDMCF_IDLE*2)  /* reload idle value into A */
    #else
      lda   #(BDMCF_IDLE/2)
    #endif      
    lslx    		  /* shift MSB into C */
    #ifdef DEBUG
      rora        /* rotate C into A */
    #else
			rola
    #endif      
    lsrx          /* shift X back to what it was */
    sta     PTA   /* create falling edge on DSCLK and write the next bit value to the port */  
    lsr     PTC   /* shift the input data bit (PTC0) into C */
		rolx          /* shift the sample into X from the bottom */
     /* transmission and reception is now complete, the result is in X */
    txa           /* move the result data to A */
    #ifdef INVERT
      coma        /* invert the data */
    #endif
  }
}

/* transmits 1 bit of logic low value and receives 1 bit */
unsigned char bdmcf_txrx_start_1(void) {
  asm {
    lda     #BDMCF_IDLE   /* preload idle state of signals into A */
     /* transmit zero and receive 1 bit */
    sta     PTA   /* bring DSCLK and DSI low */  
		nop           /* make the time between the assignement and the rising edge the same as during normal transmission */
    nop
    #ifdef INVERT
      bclr  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT  /* create rising edge on DSCLK */
    #else
      bset  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT
    #endif
		nop           /* make the time between the edges the same as during normal reception */
    #ifdef INVERT
      bset  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT  /* create falling edge on DSCLK */
    #else
      bclr  DSCLK_OUT_BITNUM,DSCLK_OUT_PORT
    #endif
    lsr     PTC   /* shift the input data bit (PTC0) into C */
    clra					/* clear the accumulator */
		rola          /* shift the sample into A from the bottom */
    #ifdef INVERT
      eor   #0x01 /* negate the received bit */
    #endif
  }
}

/* JTAG support */

/* initialises the JTAG TAP and brings the TAP into RUN-TEST/IDLE state */
void jtag_init(void) {
  unsigned char i;
  PTA  = JTAG_IDLE;    /* preload idle state into port A data register */
  #ifdef DEBUG
    DDRA = TDI_OUT_MASK | TCLK_OUT_MASK | TRST_OUT_MASK | TMS_OUT_MASK; /* RSTI_OUT and TA_OUT are inactive, the remaining OUT signals are outputs */
  #else
    DDRA = TDI_OUT_MASK | TCLK_OUT_MASK | TRST_OUT_MASK | TMS_OUT_MASK | DDRA_DDRA7; /* PTA7 is unused when not debugging, make sure it is output in such case */
  #endif
  PTC  = 0;
  DDRC = DDRC_DDRC1;    /* make pin PTC1 output (it is not bonded out on the 20 pin package anyway) */
  POCR = POCR_PTE20P;   /* enable pull-ups on PTE0-2 (unused pins) */
  /* RSTO edge capture */
  T1SC = 0;             /* enable timer 1 */
  T1SC0;                /* read the status and control register */
  #ifdef INVERT
    T1SC0 = T1SC0_ELS0A_MASK;   /* capture rising edge (invert), this write will also clear the interrupt flag if set */
  #else
    T1SC0 = T1SC0_ELS0B_MASK;   /* capture falling edge (non-invert), this write will also clear the interrupt flag if set */  
  #endif
  T1SC0 |= T1SC0_CH0IE_MASK;    /* enable input capture interrupt */
  cable_status.reset=NO_RESET_ACTIVITY;  /* clear the reset flag */  
  /* now the JTAG pins are in their default states and the RSTO sensing is set-up */
  TRST_RESET();                 /* assert TRST */
  wait_1ms(50);                 /* 50ms */
  TRST_SET();                   /* de-assert TRST */
  wait_1ms(10);                 /* 10ms */
	TMS_SET();                    /* bring TMS high */
  for (i=10;i>0;i--) {	  		  /* create 10 pulses on the TCLK line in case TRST is not connected to bring TAP to TEST-LOGIC-RESET (but it better should be as it is BKPT...) */
    TCLK_SET();
    asm (NOP); asm (NOP); asm (NOP);  /* nop padding to ensure that TCLK frequency is <0.5MHz, TCLK freq must be <= system clock / 4 and min crystal freq for 52235 is 2MHz... */
    TCLK_RESET();
    asm (NOP); asm (NOP); asm (NOP);
  }
	TMS_RESET();                  /* take TMS low */
  TCLK_SET();										/* transition TAP to RUN-TEST/IDLE */
  asm (NOP); asm (NOP); asm (NOP);  
  TCLK_RESET();
  asm (NOP); asm (NOP); asm (NOP);
}

/* trasitions the state machine from RUN-TEST/IDLE to SHIFT-DR or SHIFT-IR state */
/* if mode == 0 DR path is used, if mode != 0 IR path is used */
/* leaves TCLK high and TMS low on exit */
void jtag_transition_shift(unsigned char mode) {
	TMS_SET();                    /* bring TMS high */
  TCLK_RESET();                 /* just in case TCLK was left high */
  asm (NOP); asm (NOP); asm (NOP);  
  TCLK_SET();										/* transition TAP to SELECT DR-SCAN */
  asm (NOP); asm (NOP); asm (NOP);  
  TCLK_RESET();
  asm (NOP); asm (NOP); asm (NOP);
  if (mode!=0) {                /* select the IR path */
    TCLK_SET(); 								/* transition TAP to SELECT IR-SCAN */
    asm (NOP); asm (NOP); asm (NOP);  
    TCLK_RESET();
    asm (NOP); asm (NOP); asm (NOP);
  }
	TMS_RESET();                  /* take TMS low */
  TCLK_SET(); 								  /* transition TAP to CAPTURE-DR/IR */
  asm (NOP); asm (NOP); asm (NOP);  
  TCLK_RESET();
  asm (NOP); asm (NOP); asm (NOP);
  TCLK_SET(); 								  /* transition TAP to SHIFT-DR/IR */
  asm (NOP); asm (NOP); asm (NOP);
  TCLK_RESET();
}

/* transitions the JTAG state machine to the TEST-LOGIC-REST state */
/* the jtag must be re-initialised after this has happened since no other routine knows how to get out of this state */
void jtag_transition_reset(void) {
  unsigned char i;
	TMS_SET();                          /* bring TMS high */
  for (i=10;i>0;i--) {	  		        /* create 10 pulses on the TCLK line */
    TCLK_SET();
    asm (NOP); asm (NOP); asm (NOP);
    TCLK_RESET();
    asm (NOP); asm (NOP); asm (NOP);
  }
}

/* writes given bit stream into data/instruction path of JTAG */
/* bit_count specifies the number of bits to write */
/* data are transmitted starting with LSB of the LAST byte in the supplied buffer (for easier readability of code which uses JTAG) */
/* expects to find the TAP in SHIFT-DR or SHIFT-IR state */
/* if tap_transition == 0 leaves the TAP state unchanged, if tap_transition != 0 leaves the tap in RUN-TEST/IDLE */
void jtag_write(unsigned char tap_transition, unsigned char bit_count, unsigned char * datap) {
  unsigned char bit_no=0;
  unsigned char data;
  datap += (bit_count>>3);                                  /* each byte has 8 bits, point to the last byte in the buffer */
  if ((bit_count&0x07)==0) datap--;                         /* the size fits into the bytes precisely */
  while (bit_no<bit_count) {
    if ((bit_no&0x07)==0) data=*(datap--);                  /* fetch new byte from the buffer and update the pointer */
    if (data&0x01) TDI_OUT_SET(); else TDI_OUT_RESET();     /* assign new bit value to TDI */
    TCLK_RESET();                                           /* take TCLK low */
    data>>=1;                                               /* shift the data down */
    bit_no++;                                               /* update the bit number */
    if (bit_no==bit_count) if (tap_transition!=0) TMS_SET();/* bring TMS high if exit from the SHIFT state is required */
    TCLK_SET();                                             /* take TCLK high */
  }
  if (tap_transition) {                                     /* the TAP is now in EXIT1-DR/IR if exit was requested */
    TCLK_RESET();                                           /* take TCLK low */
    asm (NOP); asm (NOP); asm (NOP);
    TCLK_SET();                                             /* bring TCLK high */ /* transition TAP to UPDATE-DR/IR */
    asm (NOP); asm (NOP); asm (NOP);
  	TMS_RESET();                                            /* take TMS low */
    TCLK_RESET();                                           /* take TCLK low */
    asm (NOP); asm (NOP); asm (NOP);
    TCLK_SET();                                             /* bring TCLK high */ /* transition TAP to RUN-TEST/IDLE */
    asm (NOP); asm (NOP); asm (NOP);
    TCLK_RESET();                                           /* take TCLK low */
  }                                                         /* now the tap is in RUN-TEST/IDLE if exit was requested */
}

/* reads bitstream out of JTAG */
/* bit_count specifies the number of bits to read */
/* data are stored starting with LSB of the LAST byte in the supplied buffer (for easier readability of code which uses JTAG) */
/* expects to find the TAP in SHIFT-DR or SHIFT-IR state */
/* if tap_transition == 0 leaves the TAP state unchanged, if tap_transition != 0 leaves the tap in RUN-TEST/IDLE */
void jtag_read(unsigned char tap_transition, unsigned char bit_count, unsigned char * datap) {
  unsigned char bit_no=0;
  unsigned char data=0;
  datap += (bit_count>>3);                                  /* each byte has 8 bits, point to the last byte in the buffer */
  if ((bit_count&0x07)==0) datap--;                         /* the size fits into the bytes precisely */
  while (bit_no<bit_count) {
    TCLK_RESET();                                           /* take TCLK low */
    data>>=1;                                               /* shift the data down */
    if (TDO_IN_SET) data|=0x80;                             /* move the current bit into the data variable */
    bit_no++;                                               /* update the bit number */
    if ((bit_no&0x07)==0) {
      *(datap--)=data;                                      /* store the received byte into the buffer and update the pointer */
      data=0;                                               /* clear the receiving variable */
    }
    if (bit_no==bit_count) if (tap_transition!=0) TMS_SET();/* bring TMS high if exit from the SHIFT state is required */
    TCLK_SET();                                             /* take TCLK high */
  }
  if ((bit_no&0x07)!=0) {                                   /* there are bits in the data variable to be stored into the buffer */
    data>>=(8-(bit_no&0x07));                               /* shift the bits into the right place */
    *(datap)=data;                                          /* store the last bits into the buffer */
  }
  if (tap_transition) {                                     /* the TAP is now in EXIT1-DR/IR if exit was requested */
    TCLK_RESET();                                           /* take TCLK low */
    asm (NOP); asm (NOP); asm (NOP);
    TCLK_SET();                                             /* bring TCLK high */ /* transition TAP to UPDATE-DR/IR */
    asm (NOP); asm (NOP); asm (NOP);
  	TMS_RESET();                                            /* take TMS low */
    TCLK_RESET();                                           /* take TCLK low */
    asm (NOP); asm (NOP); asm (NOP);
    TCLK_SET();                                             /* bring TCLK high */ /* transition TAP to RUN-TEST/IDLE */
    asm (NOP); asm (NOP); asm (NOP);
    TCLK_RESET();                                           /* take TCLK low */
  }                                                         /* now the tap is in RUN-TEST/IDLE if exit was requested */
}