Dear All,

I have a problem when testing the V792N 16 CH QDC with the V1718 VME-USB 
Bridge on Scientific Linux 5.1 i386 (kernel 2.6.18-53.1.21.e15).

The problem is that the V792N does not response normally after a few minutes 
of continuous polling and readout of data. It seems like the V792N is hanged 
and a hardware reset of the VME system is required to bring it working again. 
If I do not poll for DREADY first and directly read the Output Buffer 
continuously, the system can work properly.

I have worked on this problem many days but I cannot find any clues to solve 
it. I have tried to use the CAENVMEDemo program (with some modifications) to 
do the same thing (polling and readout) and it works fine. CAEN technical 
support also doesn't know why the VME system is hanged. I think it might be a 
problem of MIDAS itself. I have tried with MIDAS revision 4132 and the trunk 
version, but the problem is still there. Is there any parameter in MIDAS 
(buffer size etc?) which may cause this problem? I have attached my frontend 
code and drivers for your reference.

Thank you for your kind attention.

Best Regards,
Jimmy

/********************************************************************\

  Name:         frontend.c
  Created by:   Stefan Ritt
  Modified by:  Jimmy Ngai

  Date:         July 1, 2008

  Contents:     Experiment specific readout code (user part) of
                Midas frontend. This example simulates a "trigger
                event" which are filled with VME data. The trigger
                event is filled with two banks(ADC0 and TDC0).

  $Id: frontend.c 4089 2007-11-27 07:28:17Z ritt@PSI.CH $

\********************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include "midas.h"
#include "mvmestd.h"
#include "experim.h"

#define HAVE_V792N

/* make frontend functions callable from the C framework */
#ifdef __cplusplus
extern "C" {
#endif

#ifdef HAVE_V792N
#include "vme/v792n.h"
#endif

/*-- Globals -------------------------------------------------------*/

/* The frontend name (client name) as seen by other MIDAS clients   */
char *frontend_name = "Sample Frontend";
/* The frontend file name, don't change it */
char *frontend_file_name = __FILE__;

/* frontend_loop is called periodically if this variable is TRUE    */
BOOL frontend_call_loop = FALSE;

/* a frontend status page is displayed with this frequency in ms */
INT display_period = 3000;

/* maximum event size produced by this frontend */
INT max_event_size = 10000;

/* maximum event size for fragmented events (EQ_FRAGMENTED) */
INT max_event_size_frag = 5 * 1024 * 1024;

/* buffer size to hold events */
INT event_buffer_size = 100 * 10000;

/* Hardware */
MVME_INTERFACE *myvme;

/* VME base address */
DWORD V792N_BASE = 0x32100000;

/* number of channels */
#define N_ADC      16

/*-- Function declarations -----------------------------------------*/

INT frontend_init();
INT frontend_exit();
INT begin_of_run(INT run_number, char *error);
INT end_of_run(INT run_number, char *error);
INT pause_run(INT run_number, char *error);
INT resume_run(INT run_number, char *error);
INT frontend_loop();

INT read_trigger_event(char *pevent, INT off);
INT read_scaler_event(char *pevent, INT off);

/*-- Equipment list ------------------------------------------------*/

EQUIPMENT equipment[] = {

   {"Trigger",               /* equipment name */
    {1, 0,                   /* event ID, trigger mask */
     "SYSTEM",               /* event buffer */
     EQ_POLLED,              /* equipment type */
     LAM_SOURCE(0, 0xFFFFFF),        /* event source crate 0, all stations */
     "MIDAS",                /* format */
     TRUE,                   /* enabled */
     RO_RUNNING,             /* read only when running */
     500,                    /* poll for 500ms */
     0,                      /* stop run after this event limit */
     0,                      /* number of sub events */
     0,                      /* don't log history */
     "", "", "",},
    read_trigger_event,      /* readout routine */
    },

   {""}
};

#ifdef __cplusplus
}
#endif

/********************************************************************\
              Callback routines for system transitions

  These routines are called whenever a system transition like start/
  stop of a run occurs. The routines are called on the following
  occations:

  frontend_init:  When the frontend program is started. This routine
                  should initialize the hardware.

  frontend_exit:  When the frontend program is shut down. Can be used
                  to releas any locked resources like memory, commu-
                  nications ports etc.

  begin_of_run:   When a new run is started. Clear scalers, open
                  rungates, etc.

  end_of_run:     Called on a request to stop a run. Can send
                  end-of-run event and close run gates.

  pause_run:      When a run is paused. Should disable trigger events.

  resume_run:     When a run is resumed. Should enable trigger events.
\********************************************************************/

INT init_vme_modules()
{
#ifdef HAVE_V792N
   v792n_SoftReset(myvme, V792N_BASE);
   v792n_Setup(myvme, V792N_BASE, 3);
//   v792n_Status(myvme, V792N_BASE);
#endif

   return SUCCESS;
}

/*-- Frontend Init -------------------------------------------------*/

INT frontend_init()
{
   int status;

   /* hardware initialization */

   // Open VME interface
   status = mvme_open(&myvme, 0);

   // Set am to A32 non-privileged Data
   mvme_set_am(myvme, MVME_AM_A32_ND);

   // Initialize all VME modules
   init_vme_modules();

   v792n_OfflineSet(myvme, V792N_BASE);
   v792n_DataClear(myvme, V792N_BASE);

   /* print message and return FE_ERR_HW if frontend should not be started */
   if (status != MVME_SUCCESS) {
      cm_msg(MERROR, "frontend_init", "VME interface could not be opened.");
//      return FE_ERR_HW;
   }

   return SUCCESS;
}

/*-- Frontend Exit -------------------------------------------------*/

INT frontend_exit()
{
   // Close VME interface
   mvme_close(myvme);

   return SUCCESS;
}

/*-- Begin of Run --------------------------------------------------*/

INT begin_of_run(INT run_number, char *error)
{
   // Initialize all VME modules
   init_vme_modules();

   v792n_OnlineSet(myvme, V792N_BASE);

   return SUCCESS;
}

/*-- End of Run ----------------------------------------------------*/

INT end_of_run(INT run_number, char *error)
{
   v792n_OfflineSet(myvme, V792N_BASE);
   v792n_DataClear(myvme, V792N_BASE);

   return SUCCESS;
}

/*-- Pause Run -----------------------------------------------------*/

INT pause_run(INT run_number, char *error)
{
   v792n_OfflineSet(myvme, V792N_BASE);

   return SUCCESS;
}

/*-- Resuem Run ----------------------------------------------------*/

INT resume_run(INT run_number, char *error)
{
   v792n_OnlineSet(myvme, V792N_BASE);

   return SUCCESS;
}

/*-- Frontend Loop -------------------------------------------------*/

INT frontend_loop()
{
   /* if frontend_call_loop is true, this routine gets called when
      the frontend is idle or once between every event */
   return SUCCESS;
}

/*------------------------------------------------------------------*/

/********************************************************************\

  Readout routines for different events

\********************************************************************/

/*-- Trigger event routines ----------------------------------------*/

INT poll_event(INT source, INT count, BOOL test)
/* Polling routine for events. Returns TRUE if event
   is available. If test equals TRUE, don't return. The test
   flag is used to time the polling */
{
   int i;
   DWORD lam;

   for (i = 0; i < count; i++) {
      lam = v792n_DataReady(myvme, V792N_BASE);
      if (lam)
         if (!test)
            return TRUE;
   }

   return FALSE;
}

/*-- Interrupt configuration ---------------------------------------*/

INT interrupt_configure(INT cmd, INT source, POINTER_T adr)
{
   switch (cmd) {
   case CMD_INTERRUPT_ENABLE:
      break;
   case CMD_INTERRUPT_DISABLE:
      break;
   case CMD_INTERRUPT_ATTACH:
      break;
   case CMD_INTERRUPT_DETACH:
      break;
   }
   return SUCCESS;
}

/*-- Event readout -------------------------------------------------*/

#ifdef HAVE_V792N
INT read_v792n(INT base, const char *bk_name, char *pevent, INT n_chn)
{
   INT i;
   INT nentry = 0, counter;
   DWORD data[V792N_MAX_CHANNELS+2];
   WORD *pdata;

   // Event counter
//   v792n_EvtCntRead(myvme, base, &counter);

   // Read event
   v792n_EventRead(myvme, base, data, &nentry);

   // Clear ADC
//   v792n_DataClear(myvme, base);

   // Create ADC bank
   bk_create(pevent, bk_name, TID_WORD, &pdata);

   for (i = 0; i < n_chn; i++)
      pdata[i] = 0;

   for (i = 0; i < nentry; i++) {

/*********************************************************************

  Name:         v792n.h
  Created by:   Jimmy Ngai

  Contents:     V792N 16ch. QDC include

  Based on v792.h by Pierre-Andre Amaudruz

  $Id: $
*********************************************************************/
#ifndef  V792N_INCLUDE_H
#define  V792N_INCLUDE_H

#include <stdio.h>
#include <string.h>
#include "mvmestd.h"

#ifdef __cplusplus
extern "C" {
#endif

#define  V792N_MAX_CHANNELS       (DWORD) 16
#define  V792N_REG_BASE           (DWORD) (0x1000)
#define  V792N_FIRM_REV           (DWORD) (0x1000)
#define  V792N_GEO_ADDR_RW        (DWORD) (0x1002)
#define  V792N_MCST_CBLT_RW       (DWORD) (0x1004)
#define  V792N_BIT_SET1_RW        (DWORD) (0x1006)
#define  V792N_BIT_CLEAR1_WO      (DWORD) (0x1008)
#define  V792N_SOFT_RESET         (DWORD) (0x1<<7)
#define  V792N_INT_LEVEL_WO       (DWORD) (0x100A)
#define  V792N_INT_VECTOR_WO      (DWORD) (0x100C)
#define  V792N_CSR1_RO            (DWORD) (0x100E)
#define  V792N_CR1_RW             (DWORD) (0x1010)
#define  V792N_ADER_H_RW          (DWORD) (0x1012)
#define  V792N_ADER_L_RW          (DWORD) (0x1014)
#define  V792N_SINGLE_RST_WO      (DWORD) (0x1016)
#define  V792N_MCST_CBLT_CTRL_RW  (DWORD) (0x101A)
#define  V792N_EVTRIG_REG_RW      (DWORD) (0x1020)
#define  V792N_CSR2_RO            (DWORD) (0x1022)
#define  V792N_EVT_CNT_L_RO       (DWORD) (0x1024)
#define  V792N_EVT_CNT_H_RO       (DWORD) (0x1026)
#define  V792N_INCR_EVT_WO        (DWORD) (0x1028)
#define  V792N_INCR_OFFSET_WO     (DWORD) (0x102A)
#define  V792N_LD_TEST_RW         (DWORD) (0x102C)
#define  V792N_DELAY_CLEAR_RW     (DWORD) (0x102E)
#define  V792N_FCLR_WIN_RW        (DWORD) (0x102E)
#define  V792N_BIT_SET2_RW        (DWORD) (0x1032)
#define  V792N_BIT_CLEAR2_WO      (DWORD) (0x1034)
#define  V792N_W_MEM_TEST_WO      (DWORD) (0x1036)
#define  V792N_MEM_TEST_WORD_H_WO (DWORD) (0x1038)
#define  V792N_MEM_TEST_WORD_L_WO (DWORD) (0x103A)
#define  V792N_CRATE_SEL_RW       (DWORD) (0x103C)
#define  V792N_TEST_EVENT_WO      (DWORD) (0x103E)
#define  V792N_EVT_CNT_RST_WO     (DWORD) (0x1040)
#define  V792N_IPED_RW            (DWORD) (0x1060)
#define  V792N_R_MEM_TEST_WO      (DWORD) (0x1064)
#define  V792N_SWCOMM_WO          (DWORD) (0x1068)
#define  V792N_SLIDECONST_RW      (DWORD) (0x106A)
#define  V792N_AAD_RO             (DWORD) (0x1070)
#define  V792N_BAD_RO             (DWORD) (0x1072)
#define  V792N_THRES_BASE         (DWORD) (0x1080)

WORD v792n_Read16(MVME_INTERFACE *mvme, DWORD base, int offset);
void v792n_Write16(MVME_INTERFACE *mvme, DWORD base, int offset, WORD value);
DWORD v792n_Read32(MVME_INTERFACE *mvme, DWORD base, int offset);
void v792n_Write32(MVME_INTERFACE *mvme, DWORD base, int offset, DWORD value);

int  v792n_DataReady(MVME_INTERFACE *mvme, DWORD base);
int  v792n_isEvtReady(MVME_INTERFACE *mvme, DWORD base);
int  v792n_isBusy(MVME_INTERFACE *mvme, DWORD base);
int  v792n_EventRead(MVME_INTERFACE *mvme, DWORD base, DWORD *pdest, int *nentry);
int  v792n_DataRead(MVME_INTERFACE *mvme, DWORD base, DWORD *pdest, int *nentry);
void v792n_DataClear(MVME_INTERFACE *mvme, DWORD base);
void v792n_EvtCntRead(MVME_INTERFACE *mvme, DWORD base, DWORD *evtcnt);
void v792n_EvtCntReset(MVME_INTERFACE *mvme, DWORD base);
void v792n_IntSet(MVME_INTERFACE *mvme, DWORD base, int level, int vector);
void v792n_IntEnable(MVME_INTERFACE *mvme, DWORD base, int level);
void v792n_IntDisable(MVME_INTERFACE *mvme, DWORD base);
void v792n_EvtTriggerSet(MVME_INTERFACE *mvme, DWORD base, int count);
void v792n_SingleShotReset(MVME_INTERFACE *mvme, DWORD base);
void v792n_SoftReset(MVME_INTERFACE *mvme, DWORD base);
void v792n_Trigger(MVME_INTERFACE *mvme, DWORD base);
int  v792n_ThresholdRead(MVME_INTERFACE *mvme, DWORD base, WORD *threshold);
int  v792n_ThresholdWrite(MVME_INTERFACE *mvme, DWORD base, WORD *threshold);
int  v792n_CSR1Read(MVME_INTERFACE *mvme, DWORD base);
int  v792n_CSR2Read(MVME_INTERFACE *mvme, DWORD base);
int  v792n_BitSet2Read(MVME_INTERFACE *mvme, DWORD base);
void v792n_BitSet2Set(MVME_INTERFACE *mvme, DWORD base, WORD pat);
void v792n_BitSet2Clear(MVME_INTERFACE *mvme, DWORD base, WORD pat);
WORD v792n_ControlRegister1Read(MVME_INTERFACE *mvme, DWORD base);
void v792n_ControlRegister1Write(MVME_INTERFACE *mvme, DWORD base, WORD pat);
void v792n_OnlineSet(MVME_INTERFACE *mvme, DWORD base);
void v792n_OfflineSet(MVME_INTERFACE *mvme, DWORD base);
void v792n_BlkEndEnable(MVME_INTERFACE *mvme, DWORD base);
void v792n_OverRangeEnable(MVME_INTERFACE *mvme, DWORD base);
void v792n_OverRangeDisable(MVME_INTERFACE *mvme, DWORD base);
void v792n_LowThEnable(MVME_INTERFACE *mvme, DWORD base);
void v792n_LowThDisable(MVME_INTERFACE *mvme, DWORD base);
void v792n_EmptyEnable(MVME_INTERFACE *mvme, DWORD base);
void v792n_CrateSet(MVME_INTERFACE *mvme, DWORD base, DWORD *evtcnt);
void v792n_DelayClearSet(MVME_INTERFACE *mvme, DWORD base, int delay);
int  v792n_Setup(MVME_INTERFACE *mvme, DWORD base, int mode);
void v792n_Status(MVME_INTERFACE *mvme, DWORD base);
int  v792n_isPresent(MVME_INTERFACE *mvme, DWORD base);

  enum v792n_DataType {
    v792n_typeMeasurement=0,
    v792n_typeHeader     =2,
    v792n_typeFooter     =4,
    v792n_typeFiller     =6
  };

  typedef union {
    DWORD raw;
    struct v792n_Entry {
      unsigned adc:12; // bit0 here
      unsigned ov:1;
      unsigned un:1;
      unsigned _pad_1:3;
      unsigned channel:4;
      unsigned _pad_2:3;
      unsigned type:3;
      unsigned geo:5;
    } data ;
    struct v792n_Header {
      unsigned _pad_1:8; // bit0 here
      unsigned cnt:6;
      unsigned _pad_2:2;
      unsigned crate:8;
      unsigned type:3;
      unsigned geo:5;
    } header;
    struct v792n_Footer {
      unsigned evtCnt:24; // bit0 here
      unsigned type:3;
      unsigned geo:5;
    } footer;
  } v792n_Data;

  typedef union {
    DWORD raw;
    struct {
      unsigned DataReady:1; // bit0 here
      unsigned GlobalDataReady:1;
      unsigned Busy:1;
      unsigned GlobalBusy:1;
      unsigned Amnesia:1;
      unsigned Purge:1;
      unsigned TermOn:1;
      unsigned TermOff:1;
      unsigned EventReady:1; //bit 8 here
    };
  } v792n_StatusRegister1;
  typedef union {
    DWORD raw;
    struct {
      unsigned _pad_1:1; // bit0 here
      unsigned BufferEmpty:1;
      unsigned BufferFull:1;
      unsigned _pad_2:1;
      unsigned PB:4;
      //unsigned DSEL0:1;
      //unsigned DSEL1:1;
      //unsigned CSEL0:1;
      //unsigned CSEL1:1;
    };
  } v792n_StatusRegister2;
  typedef union {
    DWORD raw;
    struct {
      unsigned _pad_1:2;
      unsigned BlkEnd:1;
      unsigned _pad_2:1;
      unsigned ProgReset:1;
      unsigned BErr:1;
      unsigned Align64:1;
    };
  } v792n_ControlRegister1;
  typedef union {
    DWORD raw;
    struct {
      unsigned MemTest:1;
      unsigned OffLine:1;
      unsigned ClearData:1;
      unsigned OverRange:1;
      unsigned LowThresh:1;
      unsigned _pad_1:1;//bit5
      unsigned TestAcq:1;
      unsigned SLDEnable:1;
      unsigned StepTH:1;
      unsigned _pad_2:2;//bits 9-10
      unsigned AutoIncr:1;
      unsigned EmptyProg:1;
      unsigned SlideSubEnable:1;
      unsigned AllTrg:1;
    };
  } v792n_BitSet2Register;

  void v792n_printEntry(const v792n_Data* v);

#ifdef __cplusplus
}
#endif

#endif // V792N_INCLUDE_H

/* emacs
 * Local Variables:
 * mode:C
 * mode:font-lock
 * tab-width: 8
 * c-basic-offset: 2
 * End:
 */

/*********************************************************************

  Name:         v792n.c
  Created by:   Jimmy Ngai

  Contents:     V792N 16ch. QDC

  Based on v792.c by Pierre-Andre Amaudruz
                
  $Id: $
*********************************************************************/
#include <stdio.h>
#include <string.h>
#include <signal.h>
#if defined(OS_LINUX)
#include <unistd.h>
#endif
#include "v792n.h"

WORD v792n_Read16(MVME_INTERFACE *mvme, DWORD base, int offset)
{
  int cmode;
  WORD data;

  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  data = mvme_read_value(mvme, base+offset);
  mvme_set_dmode(mvme, cmode);
  return data;
}

void v792n_Write16(MVME_INTERFACE *mvme, DWORD base, int offset, WORD value)
{
  int cmode;
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  mvme_write_value(mvme, base+offset, value);
  mvme_set_dmode(mvme, cmode);
}

DWORD v792n_Read32(MVME_INTERFACE *mvme, DWORD base, int offset)
{
  int cmode;
  DWORD data;

  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D32);
  data = mvme_read_value(mvme, base+offset);
  mvme_set_dmode(mvme, cmode);
  return data;
}

void v792n_Write32(MVME_INTERFACE *mvme, DWORD base, int offset, DWORD value)
{
  int cmode;
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D32);
  mvme_write_value(mvme, base+offset, value);
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
int v792n_DataReady(MVME_INTERFACE *mvme, DWORD base)
{
  int data_ready, cmode;

  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  data_ready = mvme_read_value(mvme, base+V792N_CSR1_RO) & 0x1;
  mvme_set_dmode(mvme, cmode);
  return data_ready;
}

/*****************************************************************/
int v792n_isEvtReady(MVME_INTERFACE *mvme, DWORD base)
{
  int csr;
  csr = v792n_CSR1Read(mvme, base);
  return (csr & 0x100);
}

/*****************************************************************/
int v792n_isBusy(MVME_INTERFACE *mvme, DWORD base)
{
  int status, busy, timeout, cmode;

  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  timeout = 1000;
  do {
    status = mvme_read_value(mvme, base+V792N_CSR1_RO);
    busy = status & 0x4;
    timeout--;
  } while (busy || timeout);
  mvme_set_dmode(mvme, cmode);
  return (busy != 0 ? 1 : 0);
}

/*****************************************************************/
/*
Read single event, return event length (number of entries)
Uses single vme access! (1us/D32)
*/
int v792n_EventRead(MVME_INTERFACE *mvme, DWORD base, DWORD *pdest, int *nentry)
{
#define USE_BLT_READ_2

#ifdef USE_SINGLE_READ
  DWORD hdata;
  int   cmode;

  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D32);

  *nentry = 0;
  if (v792n_DataReady(mvme, base)) {
    do {
      hdata = mvme_read_value(mvme, base);
    } while (!(hdata & 0x02000000)); // skip up to the header

    pdest[*nentry] = hdata;
    *nentry += 1;
    do {
      pdest[*nentry] = mvme_read_value(mvme, base);
      *nentry += 1;
    } while (!(pdest[*nentry-1] & 0x04000000)); // copy until the trailer

    nentry--;
  }

  mvme_set_dmode(mvme, cmode);
#endif // USE_SINGLE_READ

#ifdef USE_BLT_READ_1
  DWORD hdata, data[V792N_MAX_CHANNELS+2];
  int   cam, cmode, cnt, i;

  mvme_get_am(mvme, &cam);
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D32);

  *nentry = 0;
  if (v792n_DataReady(mvme, base)) {
    do {
      hdata = mvme_read_value(mvme, base);
    } while (!(hdata & 0x02000000)); // skip up to the header

    mvme_set_am(mvme, MVME_AM_A32_NB);
    mvme->blt_mode = MVME_BLT_BLT32;
    cnt = (hdata >> 8) & 0x3F;

    mvme_read(mvme, data, base, (cnt+1)*4);
    pdest[0] = hdata;
    for (i=1;i<=cnt+1;i++)
      pdest[i] = data[i-1];

    *nentry = cnt + 2;
  }

  mvme_set_am(mvme, cam);
  mvme_set_dmode(mvme, cmode);
#endif // USE_BLT_READ_1

#ifdef USE_BLT_READ_2
  DWORD hdata;
  int   cam, cmode, cnt;

  mvme_get_am(mvme, &cam);
  mvme_get_dmode(mvme, &cmode);

  *nentry = 0;
//  if (v792n_DataReady(mvme, base)) {
    mvme_set_am(mvme, MVME_AM_A32_NB);
    mvme->blt_mode = MVME_BLT_BLT32;
    mvme_read(mvme, pdest, base, (V792N_MAX_CHANNELS+2)*4);
    cnt = (pdest[0] >> 8) & 0x3F;
    *nentry = cnt + 2;
//  }

  mvme_set_am(mvme, cam);
  mvme_set_dmode(mvme, cmode);
#endif //USE_BLT_READ_2

  return *nentry;
}

/*****************************************************************/
/*
Read nentry of data from the data buffer. Will use the DMA engine
if size is larger than 127 bytes.
*/
int v792n_DataRead(MVME_INTERFACE *mvme, DWORD base, DWORD *pdest, int *nentry)
{
  int  cmode;

  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D32);
//  *nentry = 128;
  if (v792n_DataReady(mvme, base)) {
    mvme_read(mvme, pdest, base, *nentry*4);
  }
  mvme_set_dmode(mvme, cmode);
  return *nentry;
}

/*****************************************************************/
void v792n_DataClear(MVME_INTERFACE *mvme, DWORD base)
{
  int cmode;
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  mvme_write_value(mvme, base+V792N_BIT_SET2_RW, 0x4);
  mvme_write_value(mvme, base+V792N_BIT_CLEAR2_WO, 0x4);
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
void v792n_EvtCntRead(MVME_INTERFACE *mvme, DWORD base, DWORD *evtcnt)
{
  int cmode;

  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  *evtcnt  = mvme_read_value(mvme, base+V792N_EVT_CNT_L_RO);
  *evtcnt += (mvme_read_value(mvme, base+V792N_EVT_CNT_H_RO) << 16);
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
void v792n_EvtCntReset(MVME_INTERFACE *mvme, DWORD base)
{
  int cmode;
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  mvme_write_value(mvme, base+V792N_EVT_CNT_RST_WO, 1);
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
void v792n_IntSet(MVME_INTERFACE *mvme, DWORD base, int level, int vector)
{
  int cmode;
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  mvme_write_value(mvme, base+V792N_INT_VECTOR_WO, (vector & 0xFF));
  mvme_write_value(mvme, base+V792N_INT_LEVEL_WO, (level & 0x7));
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
void v792n_IntEnable(MVME_INTERFACE *mvme, DWORD base, int level)
{
  int cmode;
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  mvme_write_value(mvme, base+V792N_EVTRIG_REG_RW, (level & 0x1F));
  /* Use the trigger buffer for int enable/disable
  mvme_write_value(mvme, base+V792N_INT_LEVEL_WO, (level & 0x7));
  */
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
void v792n_IntDisable(MVME_INTERFACE *mvme, DWORD base)
{
  int cmode;
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  mvme_write_value(mvme, base+V792N_EVTRIG_REG_RW, 0);
  /* Use the trigger buffer for int enable/disable
     Setting a level 0 reboot the VMIC !
  mvme_write_value(mvme, base+V792N_INT_LEVEL_WO, 0);
  */
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
void v792n_EvtTriggerSet(MVME_INTERFACE *mvme, DWORD base, int count)
{
  int cmode;

  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  mvme_write_value(mvme, base+V792N_EVTRIG_REG_RW, (count & 0x1F));
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
void v792n_SingleShotReset(MVME_INTERFACE *mvme, DWORD base)
{
  int cmode;
  mvme_get_dmode(mvme, &cmode);
  mvme_set_dmode(mvme, MVME_DMODE_D16);
  mvme_write_value(mvme, base+V792N_SINGLE_RST_WO, 1);
  mvme_set_dmode(mvme, cmode);
}

/*****************************************************************/
void v792n_SoftReset(MVME_INTERFACE *mvme, DWORD base)
{