source: fact/tools/vchvtest/HV.cc

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

  Name:         HV.cc

  Created by:   Sebastian Commichau, November 2008
                commichau@phys.ethz.ch

  Contents:     Main class for HV supply
                
\********************************************************************/

#include "HV.h"

extern bool Verbose;

//
// Constructor
//
HVBoard::HVBoard(int DeviceNumber, char *DeviceName) {
   
  char Buffer[MAX_COM_SIZE];
  struct termios tio;
 
  fTimeOut  = 1;
  BoardNumber = DeviceNumber;
  BoardName = DeviceName;
  LastWrapCount = -1;
  
  // Open device
  snprintf(Buffer, MAX_COM_SIZE, "/dev/%s",DeviceName);
  if ((fDescriptor = open(Buffer, O_RDWR|O_NOCTTY|O_NDELAY)) == -1) {
    printf("Error: Could not open device #%d: %s (%d/%s)\n", DeviceNumber, DeviceName, errno, strerror(errno));
    return;
  }

  // Get current serial port settings
  if (tcgetattr(fDescriptor, &tio) == -1) {
    printf("Error: tcgetattr() failed on device #%d: %s (%d/%s)\n", DeviceNumber, DeviceName, errno, strerror(errno));
    return;   
  }

  // Set baudrate and raw mode
  if (cfsetspeed(&tio, BAUDRATE) == -1) printf("Error: Could not set baud rate of device #%d: %s (%d/%s)\n", DeviceNumber, DeviceName, errno, strerror(errno));
  cfmakeraw(&tio);
  if (tcsetattr(fDescriptor, TCSANOW, &tio ) == -1) printf("Error: tcsetattr() failed on device #%d: %s (%d/%s)\n", DeviceNumber, DeviceName, errno, strerror(errno));

  return;
}

//
// Destructor
//
HVBoard::~HVBoard() {

  if(fDescriptor != -1) close(fDescriptor);
}


// Communicate: Write and read from HV Board until fTimeOut has been reached 
//
// Returns: 0 error, 1 success, -1 fTimeOut exceeded
int HVBoard::Communicate(unsigned char* wbuf, int Bytes) {

  unsigned char rbuf[RBUF_LEN];
  int ret;
  fd_set SelectDescriptor;

  Status.BoardNumber = -1;
        
  // === Write data ===
  ret = write(fDescriptor, wbuf, Bytes);
  if (ret == -1) {
    printf("Error: Could not write data (%d/%s)\n", errno, strerror(errno));
    return 0;
  }
  else if (ret < Bytes) {
    printf("Error: Could write only %d of %d bytes\n", ret, Bytes);
    return 0;
  }
  if (Verbose) {
        printf("  %d byte(s) written: ", Bytes);
        for (int i=0; i<Bytes; i++) printf(" %#.2x", wbuf[i]);
        printf("\n");
  }

  // === Try to read until time-out ===
  FD_ZERO(&SelectDescriptor);   FD_SET(fDescriptor, &SelectDescriptor);
  struct timeval WaitTime = {(long) fTimeOut, (long) ((fTimeOut-(long) fTimeOut)*1e6)};
  if (select(fDescriptor+1, &SelectDescriptor, NULL, NULL, &WaitTime)==-1) {
    printf("Error with select() (%d/%s)\n", errno,strerror(errno));
    return 0;
  }

  // Time-out expired?
  if (!FD_ISSET(fDescriptor, &SelectDescriptor)) {
    printf("Time-out of %.2f seconds expired while reading\n", fTimeOut);
    return -1;
  }

  // Read error?    
  if ((ret = read(fDescriptor, rbuf, RBUF_LEN)) == -1) {
    printf("Read error (%d/%s)\n", errno, strerror(errno));
    return 0;
  }
  // Check wrap counter
  if (LastWrapCount != -1) {
    if ((LastWrapCount+1)%8 != (rbuf[0] & 0x70)>>4) {
      printf("Warning: Wrap counter mismatch.\n");    
    }
  }
  LastWrapCount = (rbuf[0] & 0x70)>>4;
  
  // Print result in hexadecimal and binary representation 
  if (Verbose) {
        printf("  %d byte(s) read: ", ret);
        for (int i=0; i<ret; i++) printf(" %#.2x ", rbuf[i]);
        printf("    ");
        for (int i=0; i<ret; i++) {
      for (int j=7; j>=0; j--) {
        printf("%c", (rbuf[i] & 1<<j)!=0 ? '1' : '0');
        if (j == 4) printf(" ");
      }
      printf("  ");
        }
        printf("\n");
  }
  
  // Decode result if three bytes were returned
  if (ret == 3) {
    Status.BoardNumber = rbuf[2] & 0xf;
        Status.Current = rbuf[1] + (rbuf[0]&15)*256;
        Status.Overcurrent = rbuf[0] & 128;
        Status.WrapCounter = (rbuf[0]>>4) & 7;
        Status.Reset = rbuf[2] & 128;
        Status.Acknowledge = !((rbuf[2] & 0x70) == 0x70);
        
        if (Verbose) {
          printf("  *** Board %d ***   Current: %d\n"
           "Overcurrent bit: %s    Wrap counter: %d   Reset bit: %s   Status: %s\n",
           Status.BoardNumber, Status.Current, Status.Overcurrent ? "set":"clear", 
           Status.WrapCounter, Status.Reset==false ? "clear": "set",
           Status.Acknowledge ? "OK" : "No response");
        }
  }
  
  return 1;
}


// System reset of HV board
int HVBoard::SystemReset() {
  
  unsigned char wbuf[] = {0,0,0};
  return Communicate(wbuf, 3);
}


// Read channel status
int HVBoard::ReadChannel(int Chain, int Channel) {
  
  unsigned char wbuf[] = {1<<5 | Chain<<1 | (Channel&16)>>4, Channel<<4, 0};
  return Communicate(wbuf, 3);
}


// Global set
int HVBoard::GlobalSet(int Voltage) {
  
  unsigned char wbuf[] = {1<<6 , Voltage>>8, Voltage};
  return Communicate(wbuf, 3);
}


// Channel set
int HVBoard::ChannelSet(int Chain, int Channel, int Voltage) {
  
  unsigned char wbuf[] = {3<<5 |  Chain<<1 | (Channel&16)>>4, Channel<<4 | Voltage>>8, Voltage};
  return Communicate(wbuf, 3);
}


// Synchronize board
bool HVBoard::SynchBoard() {
  
  unsigned char wbuf = 0;
  int trial = 0, ret;
  
  while(++trial<=3) {
    if((ret = Communicate(&wbuf, 1)) == 1) return true;
    if (ret==0) break;
  }
  return false;
}