analogy_device.cpp

Go to the documentation of this file.

/*
 * Copyright (C) 2012 University of Bristol, UK
 *
 * This program 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.
 *
 * This program 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; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <analogy_device.h>
#include <debug.h>
#include <math.h>
#include <sstream>

#define A4L_CHAN_AREF_GROUND 0x1;
#define A4L_CHAN_AREF_COMMON 0x2;
#define A4L_CHAN_AREF_DIFF 0x4;
#define A4L_CHAN_AREF_OTHER 0x8;

using namespace DAQ;

AnalogyDevice::AnalogyDevice(a4l_desc_t *d,std::string name,IO::channel_t *chan,size_t size) : DAQ::Device(name,chan,size), dsc(*d)
{

 int err = 0;
 a4l_sbinfo_t *sbinfo;
 a4l_chinfo_t *chinfo;

 // We need to find each subdevice index manually since idx_*_subd often fails
 // Go over all subdevices and save the indexes of the first AI, AO and DIO
 int idx_ai = -1;
 int idx_ao = -1;
 int idx_dio = -1;
 for (int i=0; i < dsc.nb_subd; i++)
 {
 err = a4l_get_subdinfo(&dsc, i, &sbinfo);
 if(err != 0)
 {
 ERROR_MSG("AnalogyDriver: a4l_get_subd_info failed, wrong subdevice index %i (err=%d)\n", i, err);
 }
 // Assign subdevice index; save just the first device if many
 if (((sbinfo->flags & A4L_SUBD_TYPES) == A4L_SUBD_AI) && (idx_ai < 0))
 idx_ai = i;
 else if (((sbinfo->flags & A4L_SUBD_TYPES) == A4L_SUBD_AO) && (idx_ao < 0))
 idx_ao = i;
 else if (((sbinfo->flags & A4L_SUBD_TYPES) == A4L_SUBD_DIO) && (idx_dio < 0))
 {
 idx_dio = i;
 }
 }

 // Get info about AI subdevice
 err = a4l_get_subdinfo(&dsc, idx_ai, &sbinfo);
 if((err == 0) && ((sbinfo->flags & A4L_SUBD_TYPES) == A4L_SUBD_AI))
 {
 subdevice[AI].id = idx_ai;
 subdevice[AI].active = 0;
 subdevice[AI].count = sbinfo->nb_chan;
 subdevice[AI].chan = new channel_t[subdevice[AI].count];
 if(!subdevice[AI].chan)
 subdevice[AI].count = 0;
 else
 for(size_t i=0; i<subdevice[AI].count; ++i)
 {
 err = a4l_get_chinfo(&dsc, idx_ai, i, &chinfo);
 // Something went wrong
 if(err < 0)
 {
 subdevice[AI].active = 0;
 subdevice[AI].count = 0;
 delete[] subdevice[AI].chan;
 break;
 }
 subdevice[AI].chan[i].active = false;
 subdevice[AI].chan[i].analog.maxdata = (1<<chinfo->nb_bits)-1;
 setAnalogGain(AI,i,1.0);
 setAnalogRange(AI,i,0);
 setAnalogZeroOffset(AI,i,0);
 setAnalogReference(AI,i,0);
 setAnalogUnits(AI,i,0);
 setAnalogDownsample(AI,i,1);
 setAnalogCounter(AI,i);
 setAnalogCalibrationValue(AI,i,0);
 }
 }
 else
 {
 subdevice[AI].active = 0;
 subdevice[AI].count = 0;
 subdevice[AI].chan = NULL;
 }

 // Get info about AO subdevice
 err = a4l_get_subdinfo(&dsc, idx_ao, &sbinfo);
 if((err == 0) && ((sbinfo->flags & A4L_SUBD_TYPES) == A4L_SUBD_AO))
 {
 subdevice[AO].id = idx_ao;
 subdevice[AO].active = 0;
 subdevice[AO].count = sbinfo->nb_chan;
 subdevice[AO].chan = new channel_t[subdevice[AO].count];
 if(!subdevice[AO].chan)
 subdevice[AO].count = 0;
 else
 for(size_t i=0; i<subdevice[AO].count; ++i)
 {
 err = a4l_get_chinfo(&dsc, idx_ao, i, &chinfo);
 // Something went wrong
 if(err < 0)
 {
 subdevice[AO].active = 0;
 subdevice[AO].count = 0;
 delete[] subdevice[AO].chan;
 break;
 }
 subdevice[AO].chan[i].active = false;
 subdevice[AO].chan[i].analog.maxdata = (1<<chinfo->nb_bits)-1;
 setAnalogGain(AO,i,1.0);
 setAnalogZeroOffset(AO,i,0);
 setAnalogRange(AO,i,0);
 setAnalogReference(AO,i,0);
 setAnalogUnits(AO,i,0);
 setAnalogCalibrationValue(AO,i,0);
 }
 }
 else
 {
 subdevice[AO].active = 0;
 subdevice[AO].count = 0;
 subdevice[AO].chan = NULL;
 }

 // Get info about DIO subdevice and set to INPUT as default
 // Then add all Digital I/O to INPUT list for the
 // IO class to handle
 err = a4l_get_subdinfo(&dsc, idx_dio, &sbinfo);
 if((err == 0) && ((sbinfo->flags & A4L_SUBD_TYPES) == A4L_SUBD_DIO))
 {
 subdevice[DIO].id = idx_dio;
 subdevice[DIO].active = 0;
 subdevice[DIO].count = sbinfo->nb_chan;
 subdevice[DIO].chan = new channel_t[subdevice[DIO].count];
 if(!subdevice[DIO].chan)
 subdevice[DIO].count = 0;
 else
 for(size_t i=0; i<subdevice[DIO].count; ++i)
 {
 subdevice[DIO].chan[i].active = false;
 subdevice[DIO].chan[i].digital.previous_value = 0;
 setDigitalDirection(i,DAQ::INPUT);
 }
 }
 else
 {
 subdevice[DIO].active = 0;
 subdevice[DIO].count = 0;
 subdevice[DIO].chan = NULL;
 }
 setActive(true);
}

AnalogyDevice::~AnalogyDevice(void)
{
 if(subdevice[AI].chan) delete[] subdevice[AI].chan;
 if(subdevice[AO].chan) delete[] subdevice[AO].chan;
 if(subdevice[DIO].chan) delete[] subdevice[DIO].chan;
 if(dsc.sbdata) a4l_close(&dsc);
}

bool AnalogyDevice::analog_exists(type_t type,index_t count) const
{
 if((type == AI && count < subdevice[AI].count) ||
 (type == AO && count < subdevice[AO].count))
 return true;
 return false;
}

// Returns number of channels available for type
size_t AnalogyDevice::getChannelCount(type_t type) const
{
 if(type != AI && type != AO && type != DIO)
 return 0;

 return subdevice[type].count;
}

bool AnalogyDevice::getChannelActive(type_t type,index_t channel) const
{
 if(channel >= getChannelCount(type))
 return false;

 return subdevice[type].chan[channel].active;
}

int AnalogyDevice::setChannelActive(type_t type,index_t channel,bool state)
{
 if(channel >= getChannelCount(type))
 return -EINVAL;

 if(type == AI)
 output(channel) = 0.0;

 if(subdevice[type].chan[channel].active && !state)
 --subdevice[type].active;
 else if(!subdevice[type].chan[channel].active && state)
 ++subdevice[type].active;

 subdevice[type].chan[channel].active = state;
 return 0;
}

size_t AnalogyDevice::getAnalogRangeCount(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0;

 int err = 0;
 a4l_chinfo_t *chinfo;
 a4l_desc_t d = dsc; // Copy descriptior because method is const

 err = a4l_get_chinfo(&d, subdevice[type].id, channel, &chinfo);
 if (err < 0)
 return 0;

 return static_cast<index_t>(chinfo->nb_rng);
}

size_t AnalogyDevice::getAnalogReferenceCount(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0;

 return 4;
}

size_t AnalogyDevice::getAnalogUnitsCount(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0;

 return 2;
}

size_t AnalogyDevice::getAnalogDownsample(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0;

 return subdevice[type].chan[channel].analog.downsample;
}

std::string AnalogyDevice::getAnalogRangeString(type_t type,index_t channel,index_t index) const
{
 if(!analog_exists(type,channel) || !(index < getAnalogRangeCount(type,channel)))
 return "";

 std::ostringstream rangeString;
 int err = 0;
 a4l_rnginfo_t *range;
 a4l_desc_t d = dsc; // Copy descriptior because method is const

 err = a4l_get_rnginfo(&d, subdevice[type].id, channel, index, &range);
 if (err < 0)
 return "";

 rangeString << (double)range->min/1000000 << " to " << (double)range->max/1000000;
 return rangeString.str();
}

std::string AnalogyDevice::getAnalogReferenceString(type_t type,index_t channel,index_t index) const
{
 if(!analog_exists(type,channel) || !(index < getAnalogReferenceCount(type,channel)))
 return "";

 switch(index)
 {
 case 0:
 return "Ground";
 case 1:
 return "Common";
 case 2:
 return "Differential";
 case 3:
 return "Other";
 default:
 return "";
 }
}

std::string AnalogyDevice::getAnalogUnitsString(type_t type,index_t channel,index_t index) const
{
 if(!analog_exists(type,channel) || !(index < getAnalogUnitsCount(type,channel)))
 return "";

 switch(index)
 {
 case 0:
 return "Volts";
 case 1:
 return "Amps";
 default:
 return "";
 }
}

index_t AnalogyDevice::getAnalogRange(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0-1;

 return subdevice[type].chan[channel].analog.range;
}

index_t AnalogyDevice::getAnalogReference(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0-1;

 return subdevice[type].chan[channel].analog.reference;
}

index_t AnalogyDevice::getAnalogUnits(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0-1;

 return subdevice[type].chan[channel].analog.units;
}

index_t AnalogyDevice::getAnalogOffsetUnits(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0-1;

 return subdevice[type].chan[channel].analog.offsetunits;
}

double AnalogyDevice::getAnalogGain(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0;

 return subdevice[type].chan[channel].analog.gain;
}

double AnalogyDevice::getAnalogZeroOffset(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return 0;

 return subdevice[type].chan[channel].analog.zerooffset;
}

int AnalogyDevice::setAnalogRange(type_t type,index_t channel,index_t index)
{
 if(!analog_exists(type,channel) || !(index < getAnalogRangeCount(type,channel)))
 return -EINVAL;

 channel_t *chan = &subdevice[type].chan[channel];
 int err = 0;
 a4l_rnginfo_t *range;

 err = a4l_get_rnginfo(&dsc, subdevice[type].id, channel, index, &range);
 if (err < 0)
 return -EINVAL;

 chan->analog.range = index;
 chan->analog.conv = (range->max-range->min)/1e6/chan->analog.maxdata;
 chan->analog.offset = -range->min/chan->analog.conv/1e6;

 /*
 * Save ourselves an extra division each timestep in the fast path.
 */
 if(type == AO)
 chan->analog.conv = 1/chan->analog.conv;

 return 0;
}

int AnalogyDevice::setAnalogReference(type_t type,index_t channel,index_t index)
{
 if(!analog_exists(type,channel) || !(index < getAnalogReferenceCount(type,channel)))
 return -EINVAL;

 subdevice[type].chan[channel].analog.reference = index;
 return 0;
}

int AnalogyDevice::setAnalogUnits(type_t type,index_t channel,index_t index)
{
 if(!analog_exists(type,channel) || !(index < getAnalogUnitsCount(type,channel)))
 return -EINVAL;

 subdevice[type].chan[channel].analog.units = index;
 return 0;
}

int AnalogyDevice::setAnalogOffsetUnits(type_t type,index_t channel,index_t index)
{
 if(!analog_exists(type,channel) || !(index < getAnalogUnitsCount(type,channel)))
 return -EINVAL;

 subdevice[type].chan[channel].analog.offsetunits = index;
 return 0;
}

int AnalogyDevice::setAnalogZeroOffset(type_t type,index_t channel,double offset)
{
 if(!analog_exists(type,channel))
 return -EINVAL;

 subdevice[type].chan[channel].analog.zerooffset = offset;
 return 0;
}

int AnalogyDevice::setAnalogGain(type_t type,index_t channel,double gain)
{
 if(!analog_exists(type,channel))
 return -EINVAL;

 subdevice[type].chan[channel].analog.gain = gain;
 return 0;
}

int AnalogyDevice::setAnalogCalibrationValue(type_t type,index_t channel,double value) {
 if(!analog_exists(type,channel))
 return -EINVAL;

 subdevice[type].chan[channel].analog.calOffset = value;
 return 0;
}

double AnalogyDevice::getAnalogCalibrationValue(type_t type,index_t channel) const
{
 if(!analog_exists(type,channel))
 return -EINVAL;

 return subdevice[type].chan[channel].analog.calOffset;
}

int AnalogyDevice::setAnalogDownsample(type_t type, index_t channel, size_t downsample_rate)
{
 if(!analog_exists(type,channel))
 return -EINVAL;

 subdevice[type].chan[channel].analog.downsample = downsample_rate;
 return 0;
}

int AnalogyDevice::setAnalogCounter(type_t type, index_t channel)
{
 if(!analog_exists(type,channel))
 return -EINVAL;

 subdevice[type].chan[channel].analog.counter = 0;
 return 0;
}

// Return the direction of the selected digital channel
direction_t AnalogyDevice::getDigitalDirection(index_t channel) const
{
 if(channel >= subdevice[DIO].count)
 return DAQ::INPUT;

 return subdevice[DIO].chan[channel].digital.direction;
}

// Enable digital channel with specific direction
int AnalogyDevice::setDigitalDirection(index_t channel,direction_t direction)
{
 if(channel >= subdevice[DIO].count)
 return -EINVAL;

 subdevice[DIO].chan[channel].digital.direction = direction;

 if(direction == DAQ::INPUT)
 return a4l_config_subd(&dsc, subdevice[DIO].id, A4L_INSN_CONFIG_DIO_INPUT, channel);
 else if(direction == DAQ::OUTPUT)
 return a4l_config_subd(&dsc, subdevice[DIO].id, A4L_INSN_CONFIG_DIO_OUTPUT, channel);

 return -EINVAL;
}

// Acquire data
void AnalogyDevice::read(void)
{
 lsampl_t sample = 0;
 double value = 0;
 int ref = 0;
 int size = 0;
 analog_channel_t *channel;
 a4l_chinfo_t *chinfo;
 a4l_rnginfo_t *rnginfo;
 int err = 0;

 for(size_t i=0; i < subdevice[AI].count; ++i)
 if(subdevice[AI].chan[i].active)
 {
 channel = &subdevice[AI].chan[i].analog;
 if(!channel->counter++)
 {

 // Get analogy reference
 switch (channel->reference)
 {
 case 0:
 ref = AREF_GROUND;
 break;
 case 1:
 ref = AREF_COMMON;
 break;
 case 2:
 ref = AREF_DIFF;
 break;
 case 3:
 ref = AREF_OTHER;
 break;
 }

 // Get channel info
 err = a4l_get_chinfo(&dsc, subdevice[AI].id, i, &chinfo);
 if(err < 0)
 rt_fprintf(stderr, "analogy_device::read::a4l_get_chinfo error: %d\n", err);

 // Get channel range info
 err = a4l_get_rnginfo(&dsc, subdevice[AI].id, i, channel->range, &rnginfo);
 if(err < 0)
 rt_fprintf(stderr, "analogy_device::read::a4l_get_rnginfo error: %d\n", err);
 size = a4l_sizeof_chan(chinfo);

 // Read 1 data sample via synchronous acq
 err = a4l_sync_read(&dsc, subdevice[AI].id, PACK(i,channel->range,ref), 0, &sample, size);
 if(err < 0)
 rt_fprintf(stderr, "analogy_device::read::a4l_sync_read error: %d\n", err);

 // Convert to decimal via a4l
 err = a4l_rawtod(chinfo, rnginfo, &value, &sample, 1);
 if(err < 0)
 rt_fprintf(stderr, "analogy_device::read::a4l_rawtod error: %d\n", err);

 // Gain, convert, and push into IO pipe
 output(i) = channel->gain * value + channel->zerooffset - channel->calOffset;
 }
 channel->counter %= channel->downsample;
 }

 size_t offset = getChannelCount(AI);
 unsigned int data = 0, mask = 0;

 // Create mask using only enabled digital channels
 for(size_t i=0; i < subdevice[DIO].count; ++i)
 if(subdevice[DIO].chan[i].active && subdevice[DIO].chan[i].digital.direction == DAQ::INPUT)
 mask |= (1<<i);

 // Read all data and output it according to channel activity
 err = a4l_sync_dio(&dsc, subdevice[DIO].id, &mask, &data);
 if(err < 0)
 rt_fprintf(stderr, "analogy_device::read::a4l_sync_dio error: %d\n", err);

 // Read only enabled digital channels one by one with mask for each bit
 for(size_t i=0; i < subdevice[DIO].count; ++i)
 if(subdevice[DIO].chan[i].active && subdevice[DIO].chan[i].digital.direction == DAQ::INPUT)
 {
 mask = (1<<i);
 output(i+offset) = (data & mask) == 0 ? 0 : 5;
 }
}

void AnalogyDevice::write(void)
{
 {
 double value;
 lsampl_t sample;
 analog_channel_t *channel;
 int ref = 0;
 int size = 0;
 a4l_chinfo_t *chinfo;
 int err = 0;

 for(size_t i=0; i < subdevice[AO].count; ++i)
 if(subdevice[AO].chan[i].active)
 {
 channel = &subdevice[AO].chan[i].analog;
 value = round(channel->gain * channel->conv * (input(i) - channel->zerooffset) + channel->offset - channel->calOffset);

 // Prevent wrap around in the data units.
 if(value > channel->maxdata)
 value = channel->maxdata;
 else if(value < 0.0)
 value = 0.0;
 sample = static_cast<lsampl_t>(value);

 // Get anaolgy reference
 switch (channel->reference)
 {
 case 0:
 ref = A4L_CHAN_AREF_GROUND;
 break;
 case 1:
 ref = A4L_CHAN_AREF_COMMON;
 break;
 case 2:
 ref = A4L_CHAN_AREF_DIFF;
 break;
 case 3:
 ref = A4L_CHAN_AREF_OTHER;
 break;
 }
 // Get channel size
 err = a4l_get_chinfo(&dsc, subdevice[AO].id, i, &chinfo);
 if(err < 0)
 rt_fprintf(stderr, "analogy_device::write::a4l_get_chinfo error: %d\n", err);
 size = a4l_sizeof_chan(chinfo);

 // Write sample
 err = a4l_sync_write(&dsc, subdevice[AO].id, PACK(i,channel->range,ref), 0, &sample, size);
 if(err < 0)
 rt_fprintf(stderr, "analogy_device::read::a4l_sync_write error: %d\n", err);
 }
 }
 {
 size_t offset = getChannelCount(AO);
 int value = 0;
 unsigned int data = 0, mask = 0;

 // Create mask and data buffer with bits to be set
 for(size_t i=0; i < subdevice[DIO].count; ++i)
 {
 value = input(i+offset) != 0.0;
 if(subdevice[DIO].chan[i].active && subdevice[DIO].chan[i].digital.direction == DAQ::OUTPUT && subdevice[DIO].chan[i].digital.previous_value != value)
 {
 subdevice[DIO].chan[i].digital.previous_value = value;
 data |= value == 0 ? (0<<i) : (1<<i); // Toggle the i-th bit for modification (set 0 or 1)
 mask |= (1<<i); // Set i-th bit to specify channels to modify
 }
 }
 // Write the data according to the mask
 if (mask)
 a4l_sync_dio(&dsc, subdevice[DIO].id, &mask, &data);
 }
}

void AnalogyDevice::doLoad(const Settings::Object::State &s)
{
 for(size_t i = 0; i < subdevice[AI].count && i < static_cast<size_t>(s.loadInteger("AI Count")); ++i)
 {
 std::ostringstream str;
 str << i;
 setChannelActive(AI,i,s.loadInteger(str.str()+" AI Active"));
 setAnalogRange(AI,i,s.loadInteger(str.str()+" AI Range"));
 setAnalogReference(AI,i,s.loadInteger(str.str()+" AI Reference"));
 setAnalogUnits(AI,i,s.loadInteger(str.str()+" AI Units"));
 setAnalogGain(AI,i,s.loadDouble(str.str()+" AI Gain"));
 setAnalogZeroOffset(AI,i,s.loadDouble(str.str()+" AI Zero Offset"));
 if(s.loadDouble(str.str()+" AI Calibration Value"))
 setAnalogCalibrationValue(AI,i,s.loadDouble(str.str()+" AI Calibration Value"));
 if(s.loadInteger(str.str()+" AI Downsample"))
 setAnalogDownsample(AI,i,s.loadInteger(str.str()+" AI Downsample"));
 }

 for(size_t i = 0; i < subdevice[AO].count && i < static_cast<size_t>(s.loadInteger("AO Count")); ++i)
 {
 std::ostringstream str;
 str << i;
 setChannelActive(AO,i,s.loadInteger(str.str()+" AO Active"));
 setAnalogRange(AO,i,s.loadInteger(str.str()+" AO Range"));
 setAnalogReference(AO,i,s.loadInteger(str.str()+" AO Reference"));
 setAnalogUnits(AO,i,s.loadInteger(str.str()+" AO Units"));
 setAnalogGain(AO,i,s.loadDouble(str.str()+" AO Gain"));
 setAnalogZeroOffset(AO,i,s.loadDouble(str.str()+" AO Zero Offset"));
 if(s.loadDouble(str.str()+" AO Calibration Value"))
 setAnalogCalibrationValue(AO,i,s.loadDouble(str.str()+" AO Calibration Value"));
 }

 for(size_t i = 0; i < subdevice[DIO].count && i < static_cast<size_t>(s.loadInteger("DIO Count")); ++i)
 {
 std::ostringstream str;
 str << i;
 setChannelActive(DIO,i,s.loadInteger(str.str()+" DIO Active"));
 setDigitalDirection(i,static_cast<DAQ::direction_t>(s.loadInteger(str.str()+" DIO Direction")));
 }
}

void AnalogyDevice::doSave(Settings::Object::State &s) const
{
 s.saveInteger("AI Count",subdevice[AI].count);
 for(size_t i = 0; i < subdevice[AI].count; ++i)
 {
 std::ostringstream str;
 str << i;
 s.saveInteger(str.str()+" AI Active",getChannelActive(AI,i));
 s.saveDouble(str.str()+" AI Calibration Value",getAnalogCalibrationValue(AI,i));
 s.saveInteger(str.str()+" AI Range",getAnalogRange(AI,i));
 s.saveInteger(str.str()+" AI Reference",getAnalogReference(AI,i));
 s.saveInteger(str.str()+" AI Units",getAnalogUnits(AI,i));
 s.saveDouble(str.str()+" AI Gain",getAnalogGain(AI,i));
 s.saveDouble(str.str()+" AI Zero Offset",getAnalogZeroOffset(AI,i));
 s.saveInteger(str.str()+" AI Downsample",getAnalogDownsample(AI,i));
 }

 s.saveInteger("AO Count",subdevice[AO].count);
 for(size_t i = 0; i < subdevice[AO].count; ++i)
 {
 std::ostringstream str;
 str << i;
 s.saveInteger(str.str()+" AO Active",getChannelActive(AO,i));
 s.saveDouble(str.str()+" AO Calibration Value",getAnalogCalibrationValue(AO,i));
 s.saveInteger(str.str()+" AO Range",getAnalogRange(AO,i));
 s.saveInteger(str.str()+" AO Reference",getAnalogReference(AO,i));
 s.saveInteger(str.str()+" AO Units",getAnalogUnits(AO,i));
 s.saveDouble(str.str()+" AO Gain",getAnalogGain(AO,i));
 s.saveDouble(str.str()+" AO Zero Offset",getAnalogZeroOffset(AO,i));
 }

 s.saveInteger("DIO Count",subdevice[DIO].count);
 for(size_t i = 0; i < subdevice[DIO].count; ++i)
 {
 std::ostringstream str;
 str << i;
 s.saveInteger(str.str()+" DIO Active",getChannelActive(DIO,i));
 s.saveInteger(str.str()+" DIO Direction",subdevice[DIO].chan[i].digital.direction);
 }
}