SPIFlash size warning.

[goodfet] / firmware / goodfet.c

/*! \file goodfet.c
  \author Travis Goodspeed
  \brief Main module.
  
  This is the main module of the GoodFET, which calls the initialization
  routines and delegates commands to the various applications.
*/


#include "platform.h"
#include "command.h"
#include "apps.h"
#include "glitch.h"

#define RESET 0x80      // not a real app -- causes firmware to reset
#define DEBUGAPP 0xFF

//! Initialize registers and all that jazz.
void init()
{
#ifdef DAC12IR
        int i;
#endif

        WDTCTL = WDTPW + WDTHOLD;                                       // Stop watchdog timer

        //LED out and on.
        PLEDDIR |= PLEDPIN;
        PLEDOUT &= ~PLEDPIN;


        /* P5.0 out and low; this is chosen for the PIC app (in which P5.0
         is !MCLR) to ensure that an attached PIC chip, if present, is
         immediately driven to reset state. A brief explanation of why this
         is important follows.

        At least dsPIC33F and PIC24H --and very likely other 16-bit PIC
        families-- draw a large amount of current when running, especially
        when using a fast clock: from 60 mA up to approx. 90 mA.  If the
        PIC target begins to run before the client can request a new ICSP
        session, which requires much less current (e.g., less than 2 mA),
        then the MSP430 chip on the GoodFET will fail to start and the FTDI
        may have trouble communicating with the client. The latter likely
        relates to the FTDI on-chip 3V3 regulator being specified up to
        only 50 mA. */


        //P5REN &= ~BIT0; //DO NOT UNCOMMENT.  Breaks GF1x support.

        //This will have to be cut soon.        Use pulling resistors instead.
        /*
        P5DIR |= BIT0;
        P5OUT &= ~BIT0;
        */

        //Setup clocks, unique to each '430.
        msp430_init_dco();
        msp430_init_uart();

        //DAC should be at full voltage if it exists.
#ifdef DAC12IR
        //glitchvoltages(0xfff,0xfff);
        ADC12CTL0 = REF2_5V + REFON;                                    // Internal 2.5V ref on
        for(i=0;i!=0xFFFF;i++) asm("nop");
        DAC12_0CTL = DAC12IR + DAC12AMP_5 + DAC12ENC; // Int ref gain 1
        DAC12_0DAT = 0xFFF; //Max voltage 0xfff
        DAC12_1CTL = DAC12IR + DAC12AMP_5 + DAC12ENC; // Int ref gain 1
        DAC12_1DAT = 0x000; //Min voltage 0x000
#endif

        /** FIXME
          
          This part is really ugly.  GSEL (P5.7) must be high to select
          normal voltage, but a lot of applications light to swing it low
          to be a nuissance.  To get around this, we assume that anyone
          with a glitching FET will also have a DAC, then we set that DAC
          to a high voltage.
          
          At some point, each target must be sanitized to show that it
          doesn't clear P5OUT or P5DIR.
        */
        P5DIR|=BIT7; P5OUT=BIT7; //Normal Supply
        //P5DIR&=~BIT7; //Glitch Supply

        //Enable Interrupts.
        //eint();
        
        #ifdef INITPLATFORM
        INITPLATFORM;
        #endif
}


//! Handle a command.
void handle(uint8_t const app,
            uint8_t const verb,
            uint32_t const len){
  int i;

  //debugstr("GoodFET");
  PLEDOUT&=~PLEDPIN;

  // find the app and call the handle fn
  for(i = 0; i < num_apps; i++){
    if(apps[i]->app == app){
      // call the app's handle fn
      (*(apps[i]->handle))(app, verb, len);
      
      // exit early
      return;
    }
  }

  // if we get here, then the desired app is not copiled in 
  // this firmware
  debugstr("App missing.");
  debughex(app);
  txdata(app, NOK, 0);
}


//! Main loop.
int main(void)
{
        volatile unsigned int i;
        unsigned char app, verb;
        unsigned long len;
        // MSP reboot count for reset input & reboot function located at 0xFFFE
        volatile unsigned int reset_count = 0;
        void (*reboot_function)(void) = (void *) 0xFFFE;

        init();
  
        txstring(MONITOR,OK,"http://goodfet.sf.net/");
  
        //Command loop.  There's no end!
        while(1)
        {
                //Magic 3
                app = serial_rx();

                // If the app is the reset byte (0x80) increment and loop
                if (app == RESET)
                {
                        reset_count++;

                        if (reset_count > 4) 
                        {
                                // We could trigger the WDT with either:
                                // WDTCTL = 0;
                                // or
                                // WDTCTL = WDTPW + WDTCNTCL + WDTSSEL + 0x00;
                                // but instead we'll jump to our reboot function pointer
                                (*reboot_function)();
                        }

                        continue;
                } 
                else 
                {
                        reset_count = 0;
                }

                verb = serial_rx();
                //len=serial_rx();
                len = rxword();

                //Read data, looking for buffer overflow.y
                if(len <= CMDDATALEN)
                {
                        for(i = 0; i < len; i++)
                        {
                                cmddata[i] = serial_rx();
                        }

                        handle(app,verb,len);
                }
                else
                {
                        //Listen to the blaberring.
                        for(i = 0; i < len; i++)
                                serial_rx();

                        //Reply with an error.
                        debugstr("Buffer length exceeded.");
                        txdata(MONITOR,NOK,0);
                }
        }
}