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  16   09 Jul 2004 Stefan Ritt Introduction of environment variable MIDASSYS
Starting from midas version 1.9.4 on, the environment variable 'MIDASSYS'
should be defined and point to the installation directory of midas. The
purpose of that is that add-on packages (like the upcoming ROME system) can
find the midas libraries and include files. It is excatly the same as for
ROOT which defines ROOTSYS and should therefore be straight forward. The
libraries should then reside in $MIDASSYS/lib (or %MIDASSYS%\lib under windows).

To remind users about this new variable, a test has been added to odbedit,
which shows a warning when starting odbedit and MIDASSYS is not defined.
  15   29 Jun 2004 Konstantin Olchanski FAQ: anonymous cvs access?
> Is the midas CVS server set-up so that I can pull the newest 
> version off the CVS server?
> What would be my CVSROOT?
> *this did not work* :)

I use:

setenv CVS_RSH ssh
cvs -d checkout midas

It works most of the time. Sometimes I get locking and "permission denied"
errors on some subdirectories, presumably when CVS is being reorganized or
when there are stale locks. Does not happen too often.

  14   22 Jun 2004 Exaos Lee FAQ: anonymous cvs access?
> In the Midas doc under "Quick Start"
> you will find the proper cvs command for accessing the latest cvs Midas
> version. The public pwd is cvs. You will only be able to checkout/update the
> package.

I cannot checkout module:
01:52:16: Operation timed out
01:52:16: cvs [checkout aborted]: end of file from server (consult above
messages if any)

Could anybody add download tar package in the WWW interface of CVS repository.
I know the original CGI script has such a feature. Thanks.
  13   21 Jun 2004 Pierre-André Amaudruz FAQ: anonymous cvs access?
> Is the midas CVS server set-up so that I can pull the newest 
> version off the CVS server?
> What would be my CVSROOT?
> *this did not work* :)
> Piotr

In the Midas doc under "Quick Start"
you will find the proper cvs command for accessing the latest cvs Midas
version. The public pwd is cvs. You will only be able to checkout/update the
  12   21 Jun 2004 Piotr Zolnierczuk FAQ: anonymous cvs access?
Is the midas CVS server set-up so that I can pull the newest 
version off the CVS server?

What would be my CVSROOT? *this did not work* :)


  11   11 Mar 2004 Renee Poutissou Creation of secondary Midas output file.
Jan , 

Do you need to log this stage 1 output?  If not, you would use the 
eventbuilder mechanism to create your stage 2 events.  
I use the eventbuilder mechanism with success for my TWIST experiment.

  10   10 Mar 2004 Stefan Ritt Creation of secondary Midas output file.
Dear Jan,

I had a look at your code. You create a gPhysicsEventHeader array, fill it, and expect the 
framework to write it to disk. But how can the framework "guess" that you want your private 
global array being written? Unfortunately it cannot do magic!

Do do what you want, you have to write a "secondary" midas file yourself. I modified your 
code to do that. First, I define the event storage like

BYTE           gSecEvent[ MAX_EVENT_SIZE ];
EVENT_HEADER   *gPhysicsEventHeader = (EVENT_HEADER *) gSecEvent;
WORD* 	       gPhysicsEventData = ( WORD * )( gPhysicsEventHeader + 1 );		

I use gSecEvent as a BYTE array, since it only contains one avent at a time, so this is more 
appropriate. Then, in the BOR routine, I open a file:

  sprintf(str, "sec%05d.mid", run_number);
  sec_fh = open(str, O_CREAT | O_RDWR | O_BINARY, 0644);

and close it in the EOR routine


The event routine now manually fills events into the secondary file:

      /* write event to secondary .mid file */
      gPhysicsEventHeader->data_size = bk_size(gPhysicsEventData);
      write(sec_fh, gPhysicsEventHeader, sizeof(EVENT_HEADER)+bk_size(gPhysicsEventData));

Note that this code is placed *inside* the for() loop over nItems, so for each detector you 
create and event and write it.

That's all you need, the full file adccalib.c is attached. I tried to produce a sec01220.mid 
file and was able to read it back with the mdump utility.

Best regards,

Attachment 1: adccalib.c

  Name:         adccalib.c
  Created by:   Stefan Ritt

  Contents:     Example analyzer module for ADC calibration. Looks
                for ADC0 bank, subtracts pedestals and applies gain
                calibration. The resulting values are appended to 
                the event as an CADC bank ("calibrated ADC"). The
                pedestal values and software gains are stored in
                adccalib_param structure which was defined in the ODB
                and transferred to experim.h.

/*-- Include files -------------------------------------------------*/

/* standard includes */
#include <stdio.h>
#include <time.h>
#include <io.h>
#include <fcntl.h>

/* midas includes */
#include "midas.h"
#include "experim.h"
#include "analyzer.h"

/* root includes */
#include <TH1F.h>
#include <TTree.h>
#include <TDirectory.h>

/* Local stuff, struct for handling analysis demo...
   using EV01_BANK as template for bank mapping */
#define N_FRONTENDS 14

/* Histo info, could be placed in ODB */
typedef struct {
    char name[ 256 ];
    char title[ 256 ];
    INT  nbins;
    float xlow;
    float xhigh; 

    {"AreaHG", "AreaHG"   , 1024, 0.0, 1023.},
    {"AreaLG", "AreaLG"   , 1024, 0.0, 1023.},
    {"TimeHi", "Time High", 1024, 0.0, 1023.},
    {"TimeLo", "Time Low" , 1024, 0.0, 1023.},
    {"Detid" , "Detector ID" , 1024, 0.0, 1023.},
    {"Slope" , "Slope"    , 1024, 0.0, 1023.}

/*-- Parameters ----------------------------------------------------*/
/* local creation of ODB struct */
GAMMA_PARAM_STR( gamma_param_str );
GAMMA_PARAM gamma_param;

/* Global ODB struct (taken care by analyzer.c) */
extern EXP_PARAM      exp_param;
extern RUNINFO        runinfo;

/*-- Module declaration --------------------------------------------*/
INT adc_calib( EVENT_HEADER*, void* );
INT adc_calib_init( void );
INT adc_calib_bor( INT run_number );
INT adc_calib_eor( INT run_number );

/*-- New Bank Area -------------------------------------------------*/
BYTE           gSecEvent[ MAX_EVENT_SIZE ];
EVENT_HEADER 	*gPhysicsEventHeader = (EVENT_HEADER *) gSecEvent;
					// Trick used for allocating MAX_EVENT_SIZE bytes for bank.
WORD* 			gPhysicsEventData = ( WORD * )( gPhysicsEventHeader + 1 );		
					// Pointer to start of first data record

/* file for secondary .mid file */
int sec_fh;

/* The module name "Gamma" is used for the ODB tree under
   /Analyzer/Parameters. It maps the experim.h gamma struct.

ANA_MODULE adc_calib_module = {
  "Gamma",                       /* module name           */  
  "Pierre",                      /* author                */
  adc_calib,                     /* event routine         */
  adc_calib_bor,                 /* BOR routine           */
  adc_calib_eor,                 /* EOR routine           */
  adc_calib_init,                /* init routine          */
  NULL,                          /* exit routine          */
  &gamma_param,                  /* parameter structure   */
  sizeof(gamma_param),           /* structure size        */
  gamma_param_str,               /* initial parameters    */

/*-- module-local variables ----------------------------------------*/

extern TDirectory *gManaHistsDir;

/* Root Histo objects */
static TH1F* gAdcHists[ N_FRONTENDS ];

/*-- init routine --------------------------------------------------*/

#define TM_N_BINS  2048
#define TM_X_LOW      0
#define TM_X_HIGH  40000

INT adc_calib_init(void)
  char name[ 256 ];
  int fe_number = 2;
  int  i;
  char title[256];

  // Some booking for demo
  // Just book the crystals from frontend 2.
  for (i=0; i < N_STRUCT_ELEMENT; i++)
    sprintf(name, "%s-%2.2i" , h[i].name, fe_number);
    sprintf(title, "%s-%2.2i", h[i].title, fe_number);
    gAdcHists[i] = (TH1F*)gManaHistsDir->GetList()->FindObject(name);
    printf("Booking Histo:%s\n", name);

    if (gAdcHists[i] == NULL)
      gAdcHists[i] = new TH1F(name, title, h[i].nbins, h[i].xlow, h[i].xhigh);
  return SUCCESS;

/*-- BOR routine ---------------------------------------------------*/

INT adc_calib_bor(INT run_number)
char str[80];

  sprintf(str, "sec%05d.mid", run_number);
  sec_fh = open(str, O_CREAT | O_RDWR | O_BINARY, 0644);
  if (sec_fh < 0)
     cm_msg(MERROR, "adc_calib_bor", "Cannot open secondary .mid file \"%s\"", str);

  return SUCCESS;

/*-- eor routine ---------------------------------------------------*/

INT adc_calib_eor(INT run_number)
  return SUCCESS;

/*-- event routine -------------------------------------------------*/

INT adc_calib(EVENT_HEADER *pheader, void *pevent)
  	INT      	n_items;
  	DWORD   	*pdata;
  	EV01_BANK *pev;
  	TREK_BANK *trek;
// Initialize the calculate output bank including the header.
	gPhysicsEventHeader->serial_number = (DWORD) - 1;
	gPhysicsEventHeader->event_id = 2;
	gPhysicsEventHeader->trigger_mask = 0;
	gPhysicsEventHeader->time_stamp = pheader->time_stamp;

// For demo assume each crystal in bank 2 is new event.  This really isn't 
// true, but it is analogous to splitting one midas event into multiple physics 
// events.

/* Get there with ID = 1 -> EVxx,  
   For demo histo EV02 EV_BANK all elements.

	Create a new bank TREK which is a structure bank.
	We are testing the breaking of a single midas event
	into individual physics events.  Thus we will take
	each crystal in EV02 and make it a separate event
	in the TREK output bank.
   	[local:Default:S]Bank switches>set TREK 1
   	for output

   Apply some calibration from the gamma ODB struct.

/* look for EV02 bank, return if not present, skip TMxx ....
   n_items: number of elements in the bank */
  	if ( !( n_items = bk_locate( pevent, "EV02", &pdata ) ) )
    	return 1;

// Loop through all items in bank.

	short nItems =  n_items/ sizeof( EV01_BANK );
	printf( "Number of bytes %d, number of items %d\n", n_items, nItems );
  	pev = (EV01_BANK *)pdata;
  	for ( short i = 0; i < nItems; i++ )
  /* fill histos not really elegant for now*/
  		gAdcHists[0]->Fill((float) pev->areahg, 1);
  		gAdcHists[1]->Fill((float) pev->arealg, 1);
  		gAdcHists[2]->Fill((float) pev->timehi, 1);
  		gAdcHists[3]->Fill((float) pev->timelo, 1);
  		gAdcHists[4]->Fill((float) pev->detid, 1);
  		gAdcHists[5]->Fill((float) pev->slop, 1);
  // create calibrated TREK bank.  Recall that this output bank mimics
  // the splitting up of the midas bank into physics events.
  		++(gPhysicsEventHeader->serial_number);  	// Update serial number.
  		bk_init32( gPhysicsEventData );				// Initialize storage.
  		bk_create( gPhysicsEventData, "TREK", TID_STRUCT, &trek );
  		trek->one = (double) pev->areahg * 1.0;
  		trek->two = (float) pev->timelo * 1.0;

  		printf("area: %e time: %f\n", trek->one, trek->two );

  		bk_close( gPhysicsEventData, trek+1 );
  		pev++; // Loop to next crystal's data.  	
      /* write event to secondary .mid file */
      gPhysicsEventHeader->data_size = bk_size(gPhysicsEventData);
      write(sec_fh, gPhysicsEventHeader, sizeof(EVENT_HEADER)+bk_size(gPhysicsEventData));

  /* close calculated bank */
  return SUCCESS;
  9   10 Mar 2004 Jan Wouters Creation of secondary Midas output file.
Dear Midas Team,

I have run into a problem with Midas and was wondering if you could explain what I 
am doing wrong.  I have included a simple demo to illustrate what I am doing and 
can send a small input data file if needed.

Every midas event for the DANCE experiment consists of many physics events.  I am 
trying to create a secondary mid file where the event boundaries are now the 
physics events rather than the midas events.  This secondary mid file will be 
analyzed using a second stage midas analyzer.

For the demo, I use the data from EV02 (one of our 15 frontends), which consists of a 
variable number of fixed length structures where each structure contains the data for 
one crystal from the DANCE detector. 
 I treat each crystal as a separate physics event and write it out in the TREK bank, 
which is a demo calculated output bank, as a separate event.   

(The only difference between this demo and our real system is that we would include 
all the crystals from the other frontends that have approximately the same time stamp 
in the output bank.  Thus the output bank would consist of a varing number of 
crystals in one event rather than the fixed one crystal per event used in this demo.)

THE CHANGES TO analyzer.c AND adccalib.c
I loop through the EV02 bank examining each crystal structure in turn.  I calculate 
"calibrated" parameters and put them into an output bank called TREK.  The unusual 
part of this example is that the TREK bank is no longer part of the main list of input 
banks, ana_trigger_bank_list[].   Instead it is now part of a new bank list called 
ana_physics_bank_list[].  See the analyzer.c file for this definition.

In adccalib.c I  create the space for this new bank as follows. 

	EVENT_HEADER 	gPhysicsEventHeaders[ MAX_EVENT_SIZE / sizeof( 
	WORD* 		gPhysicsEventData = ( WORD * )( gPhysicsEventHeaders + 1 );		

In the adc_calib routine I create the bank header as follows.  Note that the serial 
numbers will restart at 0 at the beginning of each midas event.  Should I let the serial 
number increment monotonically until the end of the run?:

	gPhysicsEventHeaders->serial_number = (DWORD) - 1;
	gPhysicsEventHeaders->event_id = 2;
	gPhysicsEventHeaders->trigger_mask = 0;
	gPhysicsEventHeaders->time_stamp = pheader->time_stamp;

In a loop that loops through all the crystals contained in EV02,  I extract each crystal, 
calibrate it, and store it in a TREK structure.  In creating the TREK bank I assume that 
each one will be a separate physics event thus I update the event serial number and 
use bk_init32 to initialize the memory.   

   	for ( short i = 0; i < nItems; i++ )
  	{	++(gPhysicsEventHeaders->serial_number);  	// Update serial number.
  		bk_init32( gPhysicsEventData );		// Initialize storage.
  		bk_create( gPhysicsEventData, "TREK", TID_STRUCT, &trek );
  		trek->one = (double) pev->areahg * 1.0;
  		trek->two = (float) pev->timelo * 1.0;

  		bk_close( gPhysicsEventData, trek+1 );
  		pev++; 					// Loop to next crystal's data. 

The output bank should consist of multiple events for each individual EV02 midas 
input event. 

 As far as I can tell the code compiles and runs fine, but I get no data in the .mid 
output file except for the ODB. I have a print statement at the beginning of each 
midas event stating how many crystals were found in the EV02 bank.  I also print out 
the calibrated value for each crystal as it is being placed in its own TREK output 
bank.  The data appears correct.

 I cannot place TREK in the input bank the way it normally is done in the examples 
because there is not a one-to-one correspondence between a midas event and a 
true physics event.  Instead one midas event has many physics events.  Thus the 
output bank needs to be in a new memory area so that I can create a custom header 
and increment the serial number properly for each event.  Our follow-on analysis 
using a second Midas analyzer only needs to analyze one physics event at a time 
rather than one Midas event at a time, which is why we are going to all the trouble to 
get this paradigm working.

I include all the code for this very simple example. 

To run the example just use the run01220.mid file I will send:

./analyzer -i run01220.mid.gz -o run01220out.mid -c settings.odb_cfg -n 50

The only thing done by the settings.odb_cfg file is to turn on the TREK output bank.  I 
have verified that the bank is on.

I believe that I must not be creating the new TREK output bank correctly so that 
midas understands that the event-by-event calculated physics data should be written 
out event-by-event.  I have pointed out several places in the above discussion where 
I might be making a mistake.

I would like to get both this example running and a similar which create Root trees, 
though the Root trees are of secondary importance.  With this example I can finish 
writing the second stage analyzer and get the DANCE collaboration moving forward 
with their analysis.  Currently, we cannot use this paradigm because I cannot create 
a secondary mid file in our stage one analysis.  I would be very grateful if you could 
take a look at this example and tell me what I am doing incorrectly.

Attachment 1: dance193.tar
  8   17 Jan 2004 Stefan Ritt Access to hardware in the MIDAS framework
> The result is strange because the get function is called all the time very 
> fast (much faster then the 9 seconds as set in the equipment) and even 
> before starting the run (I just put the flag RO_RUNNING).

This is on purpose. When the frontend is idle, it loops over the slow control 
equipment as fast as possible. This way, you see changes in your hardware very 
quickly. I see no reason to waste CPU cycles in the frontend when there are 
better things to do like reading slow control equipment. Presume you have the 
alarm system running, which turns off some equipment in case of an over 
current. You better do this as quickly as possible, not wasting up to 9 
seconds each time.

The 9 seconds you mention are for reading *EVENTS*. You have double 
functionality: First, reading the slow control system, writing updated values 
to the ODB, where someone else can display or evaluate them (in the alarm 
system for example). Second, assemble events and sending them with the other 
data to disk or tape. Only the second one gets controlled by RO_RUNNING and 
the 9 seconds. You can see this by the updating event statists on your 
frontend display, which increments only when running and then every 9 seconds.
  7   16 Jan 2004 Razvan Stefan Gornea Access to hardware in the MIDAS framework
The multimeter device is indeed to simple to use MIDAS but I am just trying 
it as a learning experience. The DAQ system to develop involves VME crates 
and general purpose I/O boards. The slow control part, especially accessing 
the I/O boards seem to me more complex then the VME access. I want to 
understand very well the "correct" way of using the MIDAS slow control 
framework before starting the project.

I chose the second method and created a meterdev.c driver (essentially a 
copy of the nulldev.c) where I changed the init. function and the get 
function. I am not sending a "INIT ..." string because for this device it 
is useless. In the get function I send a "D" and read my string. I changed 
the frontend of the example to have a new driver list (in the first try I 
eliminated the Output device but the ODB got corrupted, I guess the class 
multi needs to have defined output channels). The output channel is linked 
with nulldev and null (I guess this is like if they would not be present).

The result is strange because the get function is called all the time very 
fast (much faster then the 9 seconds as set in the equipment) and even 
before starting the run (I just put the flag RO_RUNNING).

Thanks for any help
Attachment 1: frontend.c
// Name:		frontend.c
// Created by:	Razvan Stefan Gornea
// Contents:	Slow Control frontend for a portable multimeter
// Log:			2004-01-15 14:22
//				Writing down initial code.

#include <stdio.h>
#include "midas.h"
#include "class/multi.h"
#include "device/nulldev.h"
#include "meterdev.h"
#include "bus/null.h"
#include "bus/rs232.h"

// globals variables

// frontend name
char *frontend_name = "Slow Control";
// frontend file name
char *frontend_file_name = __FILE__;
// frontend loop
BOOL frontend_call_loop = FALSE;
// frontend display refresh
INT display_period = 1000;
// maximum event size in bytes
INT max_event_size = 10000;
// maximum event size for fragments in bytes
INT max_event_size_frag = 5*1024*1024;
// buffer size in bytes
INT event_buffer_size = 10*10000;

// equipment list

// device drivers
DEVICE_DRIVER multi_driver[] = {
	{"Input", meterdev, 1, rs232, DF_INPUT},
	{"Output", nulldev, 1, null, DF_OUTPUT},
// equipment list
EQUIPMENT equipment[] = {
  { "Multimeter",         /* equipment name */
    11, 0,                /* event ID, trigger mask */
    "SYSTEM",             /* event buffer */
    EQ_SLOW,              /* equipment type */
    0,                    /* event source */
    "FIXED",              /* format */
    TRUE,                 /* enabled */
    RO_RUNNING,           /* read when running */
    9000,                 /* read every 9 sec */
    0,                    /* stop run after this event limit */
    0,                    /* number of sub events */
    1,                    /* log history every event */
    "", "", "",
    cd_multi_read,        /* readout routine */
    cd_multi,             /* class driver main routine */
    multi_driver,         /* device driver list */
    NULL,                 /* init string */
  { "" }

// routines

INT  poll_event(INT source[], INT count, BOOL test) {return 1;};
INT  interrupt_configure(INT cmd, INT source[], PTYPE adr) {return 1;};
// frontend initialization
INT frontend_init()
  return CM_SUCCESS;
// frontend exit
INT frontend_exit()
  return CM_SUCCESS;
// frontend loop
INT frontend_loop()
  return CM_SUCCESS;
// begin of run
INT begin_of_run(INT run_number, char *error)
  return CM_SUCCESS;
// end of run
INT end_of_run(INT run_number, char *error)
  return CM_SUCCESS;
// pause run
INT pause_run(INT run_number, char *error)
  return CM_SUCCESS;
// resume run
INT resume_run(INT run_number, char *error)
  return CM_SUCCESS;
Attachment 2: meterdev.c
// Name:		meter.c
// Created by:	Razvan Stefan Gornea
// Contents:	Device driver for a portable multimeter
// Log:			2004-01-15 14:22
//				Writing down initial code.

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include "midas.h"

// globals variables

#define DEFAULT_TIMEOUT 10000 // 10 secondes

typedef struct {
  int  address;

Address = INT : 1\n\
typedef struct {
  METERDEV_SETTINGS meterdev_settings; // device settings
  float         *array; // data array
  INT           num_channels; // number of channels associated with this device
  INT (*bd)(INT cmd, ...); // bus driver entry function
  void *bd_info; // private settings and data related to the bus driver
  HNDLE hkey; // ODB key for bd_info structure

// routines

// initialization function: access the ODB to creates the settings, initializes the variables
// and calls the initialization function of the bus driver
INT meterdev_init(HNDLE hkey, void **pinfo, INT channels, INT (*bd)(INT cmd, ...))
	int status, size;
	HNDLE hDB, hkeydd;

	// allocate info structure
	info = calloc(1, sizeof(METERDEV_INFO));
	*pinfo = info;
	// get handle on current experiment ODB
	cm_get_experiment_database(&hDB, NULL);
	// create METERDEV settings record
	status = db_create_record(hDB, hkey, "DD", METERDEV_SETTINGS_STR); // force the ODB structure to match the METERDEV_SETTINGS C structure
	if (status != DB_SUCCESS) {
		return FE_ERR_ODB;
	db_find_key(hDB, hkey, "DD", &hkeydd); // get handle on the DD key in the ODB associated with a certain equipment and device as pointed by the "hkey" handle
	size = sizeof(info->meterdev_settings); // get the size of the device settings structure
	db_get_record(hDB, hkeydd, &info->meterdev_settings, &size, 0); // load the device settings for the ODB, i.e. ontent of DD key
	// initialize the driver
	info->num_channels = channels; // define the nmber of channels
	info->array = calloc(channels, sizeof(float)); // allocate space for data
	info->bd = bd; // set handle on bus driver
	info->hkey = hkey; // set handle on the ODB key for the evice driver
	if (!bd) { // if handle invalid return error
		return FE_ERR_ODB;
	// call the bus driver initialization routine
	status = info->bd(CMD_INIT, info->hkey, &info->bd_info);
	if (status != SUCCESS) {
		return status;
	// initialization of device, something like ... 
	// for this device no initialization string is needed ...

  return FE_SUCCESS;

// decomission function: free memory allocation(s) and close device(s)
INT meterdev_exit(METERDEV_INFO *info)
	// call EXIT function of bus driver, usually closes device
	info->bd(CMD_EXIT, info->bd_info);
	// free local variables
	if (info->array) {
	return FE_SUCCESS;

// set channel value
INT meterdev_set(METERDEV_INFO *info, INT channel, float value)
	char str[80];
	// set channel to a specific value, something like ...
	sprintf(str, "SET %d %lf", channel, value);
	BD_GETS(str, sizeof(str), ">", DEFAULT_TIMEOUT);
	// simulate writing by storing value in local array, has to be removed in a real driver
	if (channel < info->num_channels) {
		info->array[channel] = value;
	return FE_SUCCESS;

// set all channels values
INT meterdev_set_all(METERDEV_INFO *info, INT channels, float *value)
	int  i;
	char str[1000];

	// put here some optimized form of setting all channels simultaneously like ...
	strcpy(str, "SETALL ");
	for (i=0 ; i<min(info->num_channels, channels) ; i++) {
		sprintf(str+strlen(str), "%lf ", value[i]);
	BD_GETS(str, sizeof(str), ">", DEFAULT_TIMEOUT);
	// simulate writing by storing values in local array
	for (i=0 ; i<min(info->num_channels, channels) ; i++) {
		info->array[i] = value[i];
	return FE_SUCCESS;

// get channel value
INT meterdev_get(METERDEV_INFO *info, INT channel, float *pvalue)
	int  status, i;
	char str[80];
	char ascii_number[5];

	// read value from channel, something like ...
	//sprintf(str, "GET %d", channel);
	sprintf(str, "D"); // request data
	status = BD_GETS(str, sizeof(str), "\n", DEFAULT_TIMEOUT); // read until getting a cariage return or exit on timeout
	for (i = 0; i < 4; i++) { // transfer the number
		ascii_number[i] = str[i+4];
	ascii_number[4] = '\0'; // end of string
	*pvalue = (float) atof(ascii_number); // convert from ASCII to float
	// simulate reading by copying set data from local array
	//if (channel < info->num_channels) {
	//	*pvalue = info->array[channel];
	//else {
	//	*pvalue = 0.f;
	return FE_SUCCESS;

// get all channels values
INT meterdev_get_all(METERDEV_INFO *info, INT channels, float *pvalue)
	// int  i;
	/* put here some optimized form of reading all channels. If the deviced
	does not support such a function, one can call nulldev_get() in a loop 
	strcpy(str, "GETALL");
	BD_GETS(str, sizeof(str), ">", DEFAULT_TIMEOUT);
	for (i=0 ; i<min(info->num_channels, channels) ; i++)
	pvalue[i] = atof(str+i*5); // extract individual values from reply
	/* simulate reading by copying set data from local array */
	//for (i=0 ; i<min(info->num_channels, channels) ; i++)
	//	pvalue[i] = info->array[i];
	return FE_SUCCESS;

// device driver entry point
INT meterdev(INT cmd, ...)
	va_list argptr;
	HNDLE   hKey;
	INT     channel, status;
	DWORD   flags;
	float   value, *pvalue;
	void    *info, *bd;
	va_start(argptr, cmd);
	status = FE_SUCCESS;
	switch (cmd) {
	case CMD_INIT:
		hKey = va_arg(argptr, HNDLE);
		info = va_arg(argptr, void *);
		channel = va_arg(argptr, INT);
		flags = va_arg(argptr, DWORD);
		bd = va_arg(argptr, void *);
		status = meterdev_init(hKey, info, channel, bd);
	case CMD_EXIT:
		info = va_arg(argptr, void *);
		status = meterdev_exit(info);
	case CMD_SET:
		info = va_arg(argptr, void *);
		channel = va_arg(argptr, INT);
		value = (float) va_arg(argptr, double); // floats are passed as double
		status = meterdev_set(info, channel, value);
	case CMD_SET_ALL:
		info = va_arg(argptr, void *);
		channel = va_arg(argptr, INT);
		pvalue   = (float *) va_arg(argptr, float *);
		status = meterdev_set_all(info, channel, pvalue);
	case CMD_GET:
		info = va_arg(argptr, void *);
		channel = va_arg(argptr, INT);
		pvalue  = va_arg(argptr, float*);
		status = meterdev_get(info, channel, pvalue);
	case CMD_GET_ALL:
		info = va_arg(argptr, void *);
		channel = va_arg(argptr, INT);
		pvalue  = va_arg(argptr, float*);
		status = meterdev_get_all(info, channel, pvalue);
	return status;
  6   14 Jan 2004 Stefan Ritt Access to hardware in the MIDAS framework
There is some information at

and at

http://midas/download/course/ , file "part1.ppt", expecially 
page 59 and page 62 "writing your own device driver".

So what you are missing for your application is a "device driver" for your 
multimeter. The only function it has to implement is the function CMD_INIT 
where you initialize the RS232 port, and the funciton CMD_GET, which sends 
a "R" and reads the value. Now you have two options:

1) You implement RS232 calls directly in your device driver

You link against rs232.c and directly call rs232_init() at the inizialization, 
then call rs232_write() and rs232_read() where you read your 14 ASCII 

2) You call a "bus driver" in your device driver

This method makes the device driver independent of the underlying transport 
interface. So if your next multimeter accepts the same "R" command over 
Ethernet, you can just replace the RS232 bus driver by the TCPIP bus driver 
without having to change your device driver. But I guess that method 2) is not 
worth for such a simple device like your multimeter.

So take nulldev.c or dastemp.c as your starting point, put some RS232 
initialization into the init routine and the communication via "R" into 
the "get" routine. The slow control frontend, driven by mfe.c, should then 
regularly read your multimeter and the value should appear in the ODB. Take 
the examples/slowcont/frontend.c as an example, and adjust the multi_driver[] 
list to use your new device driver (instead of the nulldev).

I would like to mention that the usage of midas only makes sense for some 
experiemnts which require event based readout, using VME or CAMAC crates. If 
your only task is to read out some devices which are called "slow control 
equipment" in the midas language, then you might be better of with labview or 
  5   14 Jan 2004 Razvan Stefan Gornea Access to hardware in the MIDAS framework
I am just starting to explore MIDAS, i.e. reading the manual and trying 
some examples. For the moment I would like to make a simple frontend that 
access a portable multimeter through RS-232 port. I think this could help 
me understand how to access hardare inside MIDAS framework. Initially I've 
started from the MiniFE.c example and tried to initialize the serial port 
on run start transition and build a readout loop in the main function. I 
know that this is not a full frontend but I was just interested in getting 
some experience with the drivers available in the distribution, in this 
case RS-232. The portable multimeter is very simple in principle, one just 
has to configure the port settings and then send character 'R' and read 14 
ASCII characters from the device. Unfortunately I could not understand how 
to invoke the driver services so I changed and started again with the 
slowcont/frontend.c example. From this example and after reading the "Slow 
Control System" section in the MIDAS manual I think that all I need to do 
is to define my own equipment structure based on the multi.c class driver 
with a single input channel (and replace the null driver with the RS-232).

Here I got stuck. I see from the code source that there is a relationship 
between drivers at all levels (even bus) and the ODB but I don't yet fully 
understand how they work. Actually for a couple of days now I am in a loop 
going from class to device to bus and then back again to class drivers 
trying to see how to create my own device driver and especially how to call 
the bus driver. It could be that the framework is invoking the drivers and 
the user just has to configure things ... up to now I didn't dare to look 
at the mfe.c.

Is there a more detailed documentation about slow control and drivers then 
the MIDAS manual? What is the data flow through the three layers system for 
drivers? What is the role of the framework and what is left to the user 

  4   18 Dec 2003 Stefan Ritt Alarm on no ping?
> I want midas alarms to go off when I cannot ping arbitrary remote hosts. Is
> there is easy/preferred way to do this? K.O.

There are "internal alarms" with type AT_EVALUATED. Just find a program 
where you can put some code which gets periodically executed (like the idle 
loop in the frontend), and so something like:

DWORD last = 0;

  if (ss_time() > last+60)
    last = ss_time();

    /* do a ping via socket(), bind() and connect() */

    if (status != CM_SUCCESS)
      al_trigger_alarm("XYZ Ping", str, "Warning", 
                       "Host is dead", AT_INTERNAL);

Pierre does the same thing in lazylogger.c, just have a look. I don't know 
how to do a ping correctly in C, I guess you have to send an UDP packet 
somewhere, but I never did it. If you find it out, please post it.

  3   27 Aug 2003 Pierre-André Amaudruz Operation under 1.9.3 with the analyzer
1) Prior upgrading midas to 1.9.3, make sure you've saved your ODB in ASCII
   format using "odbedit> save my_odb.odb", as the internal structure is
   incompatible with previous version. You will be able to restore it once
   the new odb is up using "odbedit> load my_odb.odb".

2) since version 1.9.2, the analyzer supports ROOT and PAW packages.
   The general Midas makefile build the analyzer core system mana.c
   differently depending on presence of the environment variable $ROOTSYS.

   In the case $ROOTSYS is not defined, the Makefile will create:
   ~/os/lib/mana.o, build for NO HBOOK calls.
   ~/os/lib/hmana.o, build with HBOOK calls for PAW analyzer
    (requires /cern/pro/lib to be present).

   In the case $ROOTSYS is defined and pointing to a valid root directory:
   ~/os/lib/mana.o, build for NO HBOOK calls.
   ~/os/lib/rmana.o, build for ROOT analyzer.

3) Since 1.9.2, the ~/examples/experiment contains the ROOT
   analyzer example instead of HBOOK. The local Makefile uses the source
   examples and the ~/os/lib/rmana.o for building the final user
   The previous HBOOK(PAW) analyzer has been moved into ~examples/hbookexpt
   directory. The analyzer is build using the ~/os/lib/hmana.o 

4) A new application "rmidas" is available when the system is build with
   ROOT support. This application is an initial "pure" ROOT GUI implementing
   TSocket for remote ROOT histogram display. 
   Once a ONLINE ROOT analyzer is up and running, by invoking "rmidas"
   you will be prompt for a host name. Enter the node name hosting the
   analyzer. You will be presented with a list of histogram which can
   be display in a ROOT frame environment (see attachment). 

5) The support of ROOT is also available for the logger by changing  
   the data format and the destination file name in the ODB structure.
   This option will save on file the Midas banks converted into ROOT Tree.
   This file can be opened with ROOT (see attachment).

------- ODB structure of /Logger/Channels/0/Settings
    Active                          y
    Type                            Disk
    Filename                        run%05d.root    <<<<<<<<< new extension
    Format                          ROOT            <<<<<<<<< new format
    Compression                     0
    ODB dump                        y
    Log messages                    0
    Buffer                          SYSTEM
    Event ID                        -1
    Trigger mask                    -1
    Event limit                     0
    Byte limit                      0
    Tape capacity                   0
    Subdir format                   
    Current filename                run00211.root

Attachment 1: rmidas-mlogger_root_file.jpg
  2   11 Aug 2003 Konstantin Olchanski Alarm on no ping?
I want midas alarms to go off when I cannot ping arbitrary remote hosts. Is
there is easy/preferred way to do this? K.O.
  1   06 Jun 2003 Pierre-André Amaudruz Welcome
Dear Midas users,

As you certainly aware, ELOG (Electronic Logbook) has been written
by Stefan Ritt and its functionality is part of the Midas package too.
This web site using Elog is replacing the W-Agora Forum previously setup.

You will need to register to this forum in order to gain Write access and 
possible Email notification.

We would like to encourage you to post your questions or comments at
this Midas Elog site instead of using private Email to the authors as your 
remarks are surely of interest to the other users too.

ELOG V3.1.4-2e1708b5