//-----------------------------------------------------------------------------// Code that turns a Cypress FX2 USB Controller into an USB JTAG adapter//-----------------------------------------------------------------------------// Copyright (C) 2005,2006 Kolja Waschk, ixo.de//-----------------------------------------------------------------------------// For hardware configuration, please take a look at the I/O definitions just// below and in the TD_Init() code before you actually connect your FX2 to// something. There are some board-specific initializations. Then compile with// the Keil compiler & load the resulting binary into Cypress FX2 using the// EZUSB Control Panel! Please read the README text file that should have// come together with this source code.//-----------------------------------------------------------------------------// This code is part of usbjtag. usbjtag is free software; you can redistribute// it and/or modify it under the terms of the GNU General Public License as// published by the Free Software Foundation; either version 2 of the License,// or (at your option) any later version. usbjtag is distributed in the hope// that it will be useful, but WITHOUT ANY WARRANTY; without even the implied// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the// GNU General Public License for more details.  You should have received a// copy of the GNU General Public License along with this program in the file// COPYING; if not, write to the Free Software Foundation, Inc., 51 Franklin// St, Fifth Floor, Boston, MA  02110-1301  USA//-----------------------------------------------------------------------------// This file has been derived from bulksrc.c and vend_Ax.c, both taken// from the /USB/Examples/Fx2/bulksrc/bulksrc.c delivered with CY3681// development kit from Cypress Semiconductor. They both are// Copyright (c) 2000 Cypress Semiconductor. All rights reserved.//-----------------------------------------------------------------------------#pragma NOIV               // Do not generate interrupt vectors#include "fx2.h"#include "fx2regs.h"#include "fx2sdly.h"            // SYNCDELAY macro// These are in shift.a51extern void ShiftOut(BYTE c);extern BYTE ShiftInOut(BYTE c);//-----------------------------------------------------------------------------// If you're using other pins for JTAG, please also change shift.a51!// And make sure the I/O initialization in TD_Init is correct for your setup.sbit TDI = 0xA0+0;sbit TDO = 0xA0+1;sbit TCK = 0xA0+2;sbit TMS = 0xA0+3;#define bmTDIOE bmBIT0#define bmTDOOE bmBIT1#define bmTCKOE bmBIT2#define bmTMSOE bmBIT3//-----------------------------------------------------------------------------// Define USE_MOD256_OUTBUFFER:// Saves about 256 bytes in code size, improves speed a little.// A further optimization could be not to use an extra output buffer at // all, but to write directly into EP1INBUF. Not implemented yet. When // downloading large amounts of data _to_ the target, there is no output// and thus the output buffer isn't used at all and doesn't slow down things.#define USE_MOD256_OUTBUFFER 1//-----------------------------------------------------------------------------// Global datastatic BOOL Running;static BOOL WriteOnly;static BYTE ClockBytes;static WORD Pending;#ifdef USE_MOD256_OUTBUFFER  static BYTE FirstDataInOutBuffer;  static BYTE FirstFreeInOutBuffer;#else  static WORD FirstDataInOutBuffer;  static WORD FirstFreeInOutBuffer;#endif#ifdef USE_MOD256_OUTBUFFER  /* Size of output buffer must be exactly 256 */  #define OUTBUFFER_LEN 0x100  /* Output buffer must begin at some address with lower 8 bits all zero */#else  #define OUTBUFFER_LEN 0x200#endifstatic BYTE xdata OutBuffer[OUTBUFFER_LEN] _at_ 0xE000;extern BOOL GotSUD;             // Received setup data flagextern BOOL Sleep;extern BOOL Rwuen;extern BOOL Selfpwr;BYTE Configuration;             // Current configurationBYTE AlternateSetting;          // Alternate settings//-----------------------------------------------------------------------------// "EEPROM" Content// If you want to simulate the EEPROM attached to the FT245BM in the// other hardware variant of usbjtag, put something meaningful in here//-----------------------------------------------------------------------------#include "eeprom.c"//-----------------------------------------------------------------------------// Task Dispatcher hooks//   The following hooks are called by the task dispatcher.//-----------------------------------------------------------------------------void TD_Init(void)              // Called once at startup{   WORD tmp;   Running = FALSE;   ClockBytes = 0;   Pending = 0;   WriteOnly = TRUE;   FirstDataInOutBuffer = 0;   FirstFreeInOutBuffer = 0;   /* The following code depends on your actual circuit design.      Make required changes _before_ you try the code! */   // set the CPU clock to 48MHz, enable clock output to FPGA   CPUCS = bmCLKOE | bmCLKSPD1;   // Use internal 48 MHz, enable output, use "Port" mode for all pins   IFCONFIG = bmIFCLKSRC | bm3048MHZ | bmIFCLKOE;   // If you're using other pins for JTAG, please also change shift.a51!   // activate JTAG outputs on Port C   OEC = bmTDIOE | bmTCKOE | bmTMSOE;   // power on the FPGA and all other VCCs, de-assert RESETN   IOE = 0x1F;   OEE = 0x1F;   EZUSB_Delay(500); // wait for supply to come up    // The remainder of the code however should be left unchanged...   // Make Timer2 reload at 100 Hz to trigger Keepalive packets   tmp = 65536 - ( 48000000 / 12 / 100 );   RCAP2H = tmp >> 8;   RCAP2L = tmp & 0xFF;   CKCON = 0; // Default Clock   T2CON = 0x04; // Auto-reload mode using internal clock, no baud clock.   // Enable Autopointer   EXTACC = 1;  // Enable   APTR1FZ = 1; // Don't freeze   APTR2FZ = 1; // Don't freeze   // we are just using the default values, yes this is not necessary...   EP1OUTCFG = 0xA0;   EP1INCFG = 0xA0;   SYNCDELAY;                    // see TRM section 15.14   EP2CFG = 0xA2;   SYNCDELAY;                    //    EP4CFG = 0xA0;   SYNCDELAY;                    //    EP6CFG = 0xE2;   SYNCDELAY;                    //    EP8CFG = 0xE0;   // out endpoints do not come up armed      // since the defaults are double buffered we must write dummy byte counts twice   SYNCDELAY;                    //    EP2BCL = 0x80;                // arm EP2OUT by writing byte count w/skip.   SYNCDELAY;                    //    EP4BCL = 0x80;       SYNCDELAY;                    //    EP2BCL = 0x80;                // arm EP4OUT by writing byte count w/skip.   SYNCDELAY;                    //    EP4BCL = 0x80;    }void OutputByte(BYTE d){#ifdef USE_MOD256_OUTBUFFER   OutBuffer[FirstFreeInOutBuffer] = d;   FirstFreeInOutBuffer = ( FirstFreeInOutBuffer + 1 ) & 0xFF;#else   OutBuffer[FirstFreeInOutBuffer++] = d;   if(FirstFreeInOutBuffer >= OUTBUFFER_LEN) FirstFreeInOutBuffer = 0;#endif   Pending++;}//-----------------------------------------------------------------------------// TD_Poll does most of the work. It now happens to behave just like the // combination of FT245BM and EPM7064 CPLD as mentioned in the README.// That CPLD knows two major modes: Bit banging mode and Byte shift mode// It starts in Bit banging mode.  While bytes are received from the host on// EP2OUT, each byte B of them is processed as follows://// Bit banging mode:// //   1. Remember bit 6 (0x40) in B as the "Read bit".//   2. If bit 7 (0x40) is set, switch to Byte shift mode for the coming//      X bytes ( X := B & 0x3F ), and don't do anything else now.//    3. Otherwise, set the JTAG signals as follows://        TCK high if bit 0 was set (0x01), otherwise low//        TMS high if bit 1 was set (0x02), otherwise low//        TDI high if bit 4 was set (0x10), otherwise low//    4. If "Read bit" (0x40) was set, record the state of//        TDO pin and put it as a byte (2|TDO) in the output //        FIFO _to_ the host.//// Byte shift mode:////   1. Load shift register with byte from host//   2. Do 8 times (i.e. for each bit of the byte; implemented in shift.a51)//      2a) Carry bit := TDO//      2b) Rotate shift register through carry bit//      2c) TDI := Carry bit//      2d) Raise TCK, then lower TCK.//   3. If "Read bit" was set when switching into byte shift mode,//      record the shift register content and put it into the FIFO//      _to_ the host.//// Some more (minor) things to consider to emulate the FT245BM:////   a) The FT245BM seems to transmit just packets of no more than 64 bytes//      (which perfectly matches the USB spec). Each packet starts with//      two non-data bytes (I use 0x31,0x60 here). A USB sniffer on Windows//      might show a number of packets to you as if it was a large transfer//      because of the way that Windows understands it: it _is_ a large//      transfer until terminated with an USB packet smaller than 64 byte.////   b) The Windows driver expects to get some data packets (with at least//      the two leading bytes 0x31,0x60) immediately after "resetting" the//      FT chip and then in regular intervals. Otherwise a blue screen may//      appear... In the code below, I make sure that every 10ms there is//      some packet.////   c) Vendor specific commands to configure the FT245 are mostly ignored//      in my code. Only those for reading the EEPROM are processed. See//      DR_GetStatus and DR_VendorCmd below for my implementation.////   All other TD_ and DR_ functions remain as provided with CY3681.////-----------------------------------------------------------------------------void TD_Poll(void)              // Called repeatedly while the device is idle{   if(!Running) return;      if(!(EP1INCS & bmEPBUSY))   {      if(Pending > 0)      {         BYTE o, n;         AUTOPTRH2 = MSB( EP1INBUF );         AUTOPTRL2 = LSB( EP1INBUF );                XAUTODAT2 = 0x31;         XAUTODAT2 = 0x60;                if(Pending > 0x3E) { n = 0x3E; Pending -= n; }                      else { n = Pending; Pending = 0; };                o = n;#ifdef USE_MOD256_OUTBUFFER         AUTOPTR1H = MSB( OutBuffer );         AUTOPTR1L = FirstDataInOutBuffer;         while(n--)         {            XAUTODAT2 = XAUTODAT1;            AUTOPTR1H = MSB( OutBuffer ); // Stay within 256-Byte-Buffer         };         FirstDataInOutBuffer = AUTOPTR1L;#else         AUTOPTR1H = MSB( &(OutBuffer[FirstDataInOutBuffer]) );         AUTOPTR1L = LSB( &(OutBuffer[FirstDataInOutBuffer]) );         while(n--)         {            XAUTODAT2 = XAUTODAT1;            if(++FirstDataInOutBuffer >= OUTBUFFER_LEN)            {               FirstDataInOutBuffer = 0;               AUTOPTR1H = MSB( OutBuffer );               AUTOPTR1L = LSB( OutBuffer );            };         };#endif         SYNCDELAY;         EP1INBC = 2 + o;         TF2 = 1; // Make sure there will be a short transfer soon      }      else if(TF2)      {         EP1INBUF[0] = 0x31;         EP1INBUF[1] = 0x60;         SYNCDELAY;         EP1INBC = 2;         TF2 = 0;      };   };   if(!(EP2468STAT & bmEP2EMPTY) && (Pending < OUTBUFFER_LEN-0x3F))   {      BYTE i, n = EP2BCL;      AUTOPTR1H = MSB( EP2FIFOBUF );      AUTOPTR1L = LSB( EP2FIFOBUF );      for(i=0;i<n;)      {         if(ClockBytes > 0)         {            BYTE m;            m = n-i;            if(ClockBytes < m) m = ClockBytes;