For some time now, we have been thinking of updating the programming interface
for the VME bus interface drivers- mvmestd.h.

Until recently, we only had one type of vme interface- the PowerPC and
Universe-II based Motorolla MVME230x single board computers running VxWorks, and
that is the only VME interface supported by the present mvmestd.h & co in the
midas cvs.

Now we also have the Intel-PC and Universe-II based VMIC-VME single board
computers running Linux (RHL9 and RHEL4). They come with their own VME drivers
and interface library (from VMIC), and we (Pierre and myself) wrote a simplified
MIDAS-style library for using it with our ADC and TDC drivers.

After working with the VMIC-VME based systems this Summer, I am about to commit
our VME ADC and TDC drivers to MIDAS CVS. Since they use our VMIC-VME library, I
was inspired to integrate our library with the existing MIDAS VME API.

Both VME interfaces we use, MVME230x and VMIC-VME, use the same Universe-II
PCI-to-VME bridge. This brodge (+ OS drivers) provides memory mapped access to
VME directly from user memory space. Other VME interfaces require more
complicated interfacing and I tried to accomodate them in my design.

Note that this design is incomplete, it only has the VME features that we
currently use. I expect that the missing features (interrupts, DMA) will be
added to the "MIDAS VME API" as we start using them. Alternatively, they may be
implemented as interface-dependant "extensions".

So here goes:

void* mvme_getHandleA16(int crate,mvme_addr_t vmeA16addr,int numbytes,int vmeamod);
void* mvme_getHandleA24(int crate,mvme_addr_t vmeA24addr,int numbytes,int vmeamod);
void* mvme_getHandleA32(int crate,mvme_addr_t vmeA32addr,int numbytes,int vmeamod);

void mvme_writeD8(void* handle,int offset,int data);
void mvme_writeD16(void* handle,int offset,int data);
void mvme_writeD32(void* handle,int offset,int data);

int  mvme_readD8(void* handle,int offset);
int  mvme_readD16(void* handle,int offset);
int  mvme_readD32(void* handle,int offset);

The "getHandle" methods return a handle for accessing the required VME address
space. For Universe-II based drivers with direct memory mapping, the handle is a
pointer to the vme-mapped memory and can be directly dereferenced (after casting
from void*). For other drivers, it may be a pointer to an internal data
structure or whatever.

The "readDnn" and "writeDnn" methods implement the single-word vme transfers. It
is intended that directly mapped interfaces (Universe-II) can implement them as
"extern inline" (RTFM C docs) for maximum efficiency.

I am still struggling with a specification for vme block transfers. How does one
specify chained transfers? (mimic "man readv" using "struct iovec"?) How to
specify when the transfers stop (on word count, on BERR, etc). How to specify
FIFO modes (where the vme address is not incremented, all data is read from the
same address. The Universe-II bridge does not have this mode, others do). How to
decode whether to use DMA or not? (The VMIC-VME DMA driver has high startup
overhead, short transfers are faster using PIO more).

Anyhow, I do not need those advanced features immediately, so I omit them.

An implementation of this new interface will be commited to
midas/drivers/bus/vmicvme.{c,h} (and eventually I will modify vxVME.c to
conform). Drivers for sundry CAEN VME modules that use the new interface will be
commited to midas/drivers/divers (where I see drivers for other VME stuff).

Feedback is most welcome. I will try to get the stuff commited within the next
few days, plus a few days to shake down any bugs introduced during midasification.

K.O.

Good that you brought up the MIDAS VME API again, since this is still not complete, but
has to be completed soon.

Let me summarize the goals:

- have a single set of functions which can be used with all VME CPUs/Interfaces at our
institutes. Using this technique, one can change the interface or CPU and still keep
the same frontend source code. This was already successfully done with the MIDAS CAMAC
standard (as defined in mcstd.h)

- base any ADC/TDC driver we write on that API, so these modules can be used with any
CPU/Interface without changing the driver

- have a simple and easy to understand set of functions

- "cover" any specialities from the drivers, like memory mapping. 

Especially this point is very delicate. If one explicitely uses memory mapping in the
API, one cannot use interfaces which do not support this (like the Struck SIS3100). So
one should only use explicity vme_read/vme_write functions. Now people might argue that
going for each single access through a function is an overhead as compared to a memory
mapped operation. This might be true (even with inline functions of modern C
compilers), but it should be small on fast computers. Typically a single VME operation
take ~1us, while a function call takes much less.

Regarding the API implementation, I see now three "philosophies":

1) Handle oriented. One obtains a handle for each VME crate for each addressing mode,
then uses this handle for subsequent operation. This is the way the proposal from K.O.
is written.

2) Parameter oriented. There is no handle visible to the user code. All parameters are
passed in each call, like

mvme_read(crate, address_mode, vme_amod, source_addr, destination_addr, num_bytes);

3) ioctl() based. Same as 2), but the parameters like the address mode only get changed
via ioctl() when needed, like

vme_ioctl(request, parameter)   such as
 
   vme_ioctl(SET_CRATE, 1);
   vme_ioctl(MVME_AMOD, A24);
   mvme_read(source_addr, destination_addr, num_bytes);

This is how the current mvmestd.h is defined and how the
midas\drivers\bus\sis3100\sis3100.c is implemented.

Now the question is: should we implement 1), 2) or 3) ?

I had already lots of discussions with Pierre, and he convinced me that the ioctl() way
is not very nice. The advantage is that there is only one function to change
everything, so the complete API would be only 5 functions (init, exit, read, write,
ioctl), but of course there are many parameters to the ioctl() function. 

On the other hand I do not like the option 1). If you have five crates on a single PC
(and that's what we will have in our MEG experiment), you need 5x3 handles. If you use
many nested subroutines in your event readout, you have to pass lots of handles around.
I do not like option 2) as well, beacause each VME call contains many parmeters, which
make it hard to read.

So I would propose the following: We implement something like 3), but with explicit
routines:

  mvme_set_crate()   each funciton has a _get_ partner, like mvme_get_crate()
  mvme_set_address_mode()
  mvme_set_amod()
  mvme_set_blocktransfer()
  mvme_set_fifomode()             // speciality of the SIS3100 interface, write a
                                  // block of data to the same address
  ...

  mvme_read(vme_address, dest_addr, num_bytes);
  mvme_write(src_addr, vme_address, num_bytes);

It might look unfamiliar to have to set the address mode explicitely, but in practice
one typically has a few configuration calls in A16 mode, then the data readout in A32
mode. So omitting the address mode in the vme_read/write calls saves typing effort.

Since one does not use explicit handles, they have to stored internally in the driver.
I did this in the sis3100.c, and found that this overhead is negligible. The
implementation if of course not thread save, but does anybody use threads in the
experiment? I guess not.

Now I would like to hear anybody's comments. If we agree on this method, we have to
define a complete set of functions mvme_set_xxx. If we get a new interface in the
future which has new functionality (like 2eVME block transfers), we have to change the
API each time (while with the ioctl() we only would have to add one parameter). Or
maybe we can make a more generic mvme_set_vme_mode(mode), where mode could be fifomode,
2eVME mode, chained block transfer mode and so on.

Now there might be experiments which require the last bit of performance at the
frontend. They can decide to use the MIDAS API with some performance overhead, or they
can call directly the native driver API, but then be locked to the API. So everybody
has to decide himself.

I meet with Pierre end of September, and would like to finalize the API at that time.
So please give it a thought and let me know.

Best regards,

  Stefan

Anothe idea which comes to my mind, we could make it kind of object oriented, like

typedef struct {
  int handle;
  int crate;
  int amod;
  int fifo_mode;
  ...
} MVME_INTERFACE;

main()
{
  MVME_INERFACE *vme;

  vme = mvme_init(); // allocated and fills MVME_INTERFACE structure

  mvme_set_crate(vme, crate_no);
  mvme_set_address_mode(vme, A24);
  ...

  mvme_read(vme, vme_address, dest_addr, num_bytes);
  mvme_exit(vme);    // frees memory allocated in mvme_init()
}

------------------------------------------

This way we would only have one structure containing all required parameters, and get/set
functions for it, like the OO textbooks propose it. This would actually make it thread
save. The "vme" pointer from above still has to be passed around to subroutines, but a
single pointer is better than lots of handles.

> Good that you brought up the MIDAS VME API again, since this is still not complete, but
> has to be completed soon.

Right, but I can only complete the parts that I thought of and for which I already have
code. This leaves out support for DMA (read: any block transfers) and interrupts.

> Let me summarize the goals:
> - have a single set of functions which can be used with all VME CPUs/Interfaces at our
> institutes. Using this technique, one can change the interface or CPU and still keep
> the same frontend source code. This was already successfully done with the MIDAS CAMAC
> standard (as defined in mcstd.h)

Well, all interfaces are different and no amount of software will make them look all the
same. I am now facing this problem with the Wiener CCUSB CAMAC-USB2 interface. I can
implement all of mcstd.h, but the interface is intended to be used by downloading it with a
CAMAC readout program and mcstd.h knows nothing about that.

> - base any ADC/TDC driver we write on that API, so these modules can be used with any
> CPU/Interface without changing the driver

Right. Most useful.

> - have a simple and easy to understand set of functions

Right.

> - "cover" any specialities from the drivers, like memory mapping.

Exactly. We are facing a tricky task of inventing one API for two completely different
modes of operation- purely memory mapped access on UniverseII based hardware and message
passing access for the SIS3100 and VMUSB (Wiener VME-USB2).

> So one should only use explicity vme_read/vme_write functions.

Rightey-ho. The fly in the ointement is that all VME ADC and TDC drivers in TRIUMF are
written assuming memory mapped access, and I will not convert them to vme_read/vme_write
overnight (think of testing).

> So I would propose the following:
> 
>   mvme_set_crate()   each funciton has a _get_ partner, like mvme_get_crate()
>   mvme_set_address_mode()
>   mvme_set_amod()
>   mvme_set_blocktransfer()
>   mvme_set_fifomode()             // speciality of the SIS3100 interface, write a
>                                   // block of data to the same address
>   ...
> 
>   mvme_read(vme_address, dest_addr, num_bytes);
>   mvme_write(src_addr, vme_address, num_bytes);

This is compatible with what we do now and I will look into implementing this for
VMIC/Linux and MVME/VxWorks interfaces.

> Now I would like to hear anybody's comments. If we agree on this method, we have to
> define a complete set of functions mvme_set_xxx.

We currently require only single-word transfers so we can concentrate on mvme_set_xxx for
block-transfers later.

> If we get a new interface in the
> future which has new functionality (like 2eVME block transfers), we have to change the
> API each time (while with the ioctl() we only would have to add one parameter).

This amounts to the same thing: add a new function or add a new ioctl() call.

> maybe we can make a more generic mvme_set_vme_mode(mode), where mode could be fifomode,
> 2eVME mode, chained block transfer mode and so on.

This is a can of worms and I would rather postpone discussion of block transfers. To give
you a taste: UniverseII does not have a "fifo mode"- it *always* increments the vme address
 (silly). A fifo mode can be emulated using chained transfers (read 256 bytes from
addresses A through A+256, then read 256 more from address A, etc.), but the present VMIC
VME library does not support chained transfers. On VxWorks, we do not even have a driver
for the DMA engine, so not block transfers there at all.

I will now think about and post an updated proposal for mvmestd.h

K.O.

P.S. There is a proposal for musbstd.h heading your way, too.

> Right, but I can only complete the parts that I thought of and for which I already have
> code. This leaves out support for DMA (read: any block transfers) and interrupts.

DMA should be simple. We have a dma_flag in the MVME_INTERFACE structure, which only needs to
be set with mvme_set_dma_mode(...). The mvme_read/write subroutine then checks this flag and
calls the appropriate routine from the native API. About interrupts I haven't thought so much.
Does TRIUMF use interrupts anywhere? Or are all midas frontends in polled mode?

> Well, all interfaces are different and no amount of software will make them look all the
> same. 
>
> > - "cover" any specialities from the drivers, like memory mapping.
> 
> Exactly. We are facing a tricky task of inventing one API for two completely different
> modes of operation- purely memory mapped access on UniverseII based hardware and message
> passing access for the SIS3100 and VMUSB (Wiener VME-USB2).

Not all the same, but some common denominator. The memory mapped architecture can probably be
hidden in an API. So if one calls mvme_read/write, the routine checks if that region is already
mapped, and maps it if necessary. Then all you need is a proper offset and a memcpy(). Checking
about mapping causes some overhead. You have to check a hash table or a linked list which takes
time. But I think (see previous message) that this overhead should be small compared with the
IO operation. 

> I am now facing this problem with the Wiener CCUSB CAMAC-USB2 interface. I can
> implement all of mcstd.h, but the interface is intended to be used by downloading it with a
> CAMAC readout program and mcstd.h knows nothing about that.

Downloading a program you probably cannot cover with a common API, you are right. The problem
with USB is that you can only make ~1000 transfers per second, even with 2.0. So if you want
more, you need the old list concept.
> > So one should only use explicity vme_read/vme_write functions.
> 
> Rightey-ho. The fly in the ointement is that all VME ADC and TDC drivers in TRIUMF are
> written assuming memory mapped access, and I will not convert them to vme_read/vme_write
> overnight (think of testing).

You don't have to. This question only comes up if you (have to) use a non-memory mapped
interface. You can then either write then two separate drivers, or one driver and two MVME APIs.

> > Now I would like to hear anybody's comments. If we agree on this method, we have to
> > define a complete set of functions mvme_set_xxx.
> 
> We currently require only single-word transfers so we can concentrate on mvme_set_xxx for
> block-transfers later.

I need block transfers end of this month, so we should it include it in our current discussion.
The problem is that I use our (own) DRS2 waveform digitizing board, where each board produces
70kB of data per event. In non-DMA mode, the transfer would take forever.

> > maybe we can make a more generic mvme_set_vme_mode(mode), where mode could be fifomode,
> > 2eVME mode, chained block transfer mode and so on.
> 
> This is a can of worms and I would rather postpone discussion of block transfers. To give
> you a taste: UniverseII does not have a "fifo mode"- it *always* increments the vme address
>  (silly). A fifo mode can be emulated using chained transfers (read 256 bytes from
> addresses A through A+256, then read 256 more from address A, etc.), but the present VMIC
> VME library does not support chained transfers. On VxWorks, we do not even have a driver
> for the DMA engine, so not block transfers there at all.

If a native API does not support block transfer, the MVME driver should just ignore the DMA
setting. A ADC driver might then run slower, but still run. 

> I will now think about and post an updated proposal for mvmestd.h

Please also consider elog:221, I guess this is a cleaner and more flexible way of implementing
any MXXX standard.

- Stefan

I manage to access some vme modules with the older vmicvme interface and seemed
confused with the
new interface as the sample code provided does not have a specific test sample.
The test code
provided in the earlier version for accessing  V792 32ch. QDC was quite handy,
how can I apply it
for the new interface?  

> I manage to access some vme modules with the older vmicvme interface and seemed
> confused with the
> new interface as the sample code provided does not have a specific test sample.
> The test code
> provided in the earlier version for accessing  V792 32ch. QDC was quite handy,
> how can I apply it
> for the new interface?  

Hello Ian,

I'm in the process of updating the V1190B, V792 and other to the new mvmestd.
These drivers will soon be committed to the repository.

Cheers, Pierre-André 

...
install: darwin/bin/dio: No such file or directory
make: *** [install] Error 71

404,405c404,405
< $(BIN_DIR)/mcnaf: $(UTL_DIR)/mcnaf.c $(DRV_DIR)/camac/camacrpc.c
<       $(CC) $(CFLAGS) $(OSFLAGS) -o $@ $(UTL_DIR)/mcnaf.c $(DRV_DIR)/camac/camacrpc.c $(LIB) $(LIBS)
---
> $(BIN_DIR)/mcnaf: $(UTL_DIR)/mcnaf.c $(DRV_DIR)/bus/camacrpc.c
>       $(CC) $(CFLAGS) $(OSFLAGS) -o $@ $(UTL_DIR)/mcnaf.c $(DRV_DIR)/bus/camacrpc.c $(LIB) $(LIBS)
438c438,439
<       @for i in mserver mhttpd odbedit mlogger ; \
---
> 
>       @for i in mserver mhttpd odbedit mlogger dio ; \
444,447d444
<       chmod +s $(SYSBIN_DIR)/mhttpd
< 
< ifeq ($(OSTYPE),linux)
<       install -v -m 755 $(BIN_DIR)/dio $(SYSBIN_DIR)
449c446
< endif
---
>       chmod +s $(SYSBIN_DIR)/mhttpd

diff Makefile Makefile.modify
-------------------------------------
404,405c404,405
< $(BIN_DIR)/mcnaf: $(UTL_DIR)/mcnaf.c $(DRV_DIR)/bus/camacrpc.c
<       $(CC) $(CFLAGS) $(OSFLAGS) -o $@ $(UTL_DIR)/mcnaf.c $(DRV_DIR)/bus/camacrpc.c $(LIB) $(LIBS)
---
> $(BIN_DIR)/mcnaf: $(UTL_DIR)/mcnaf.c $(DRV_DIR)/camac/camacrpc.c
>       $(CC) $(CFLAGS) $(OSFLAGS) -o $@ $(UTL_DIR)/mcnaf.c $(DRV_DIR)/camac/camacrpc.c $(LIB) $(LIBS)

• Anonymous checkout can be done now with
  svn co svn+ssh://svn@savannah.psi.ch/afs/psi.ch/project/meg/svn/midas/trunk midas
  svn co svn+ssh://svn@savannah.psi.ch/afs/psi.ch/project/meg/svn/mxml/trunk mxml
  Use password svn (you might have to enter it several times). The mxml package is now outside from midas, so you have to check it out separately.
  
• Non-anonymous access (for commits!) is only possible if you have an account at PSI. While it is possible via
  svn co svn+ssh://<your_name>@savannah.psi.ch/afs/psi.ch/project/meg/svn/midas/trunk midas
  it is more convenient if you access the repository via AFS, since then you only have to obtain a valid AFS token once a day and do not have to supply passwords on each SVN access
  
• Before you do a checkout, delete (or rename) your old CVS working directory
  
• Subversion does not use file revisions, but a global revision number for the whole repository, which is now at 2752. To get some idea about subversion, read this very good book
  
• The Web access to the repository is at http://savannah.psi.ch/viewcvs/trunk/?root=midas
  
• The ViewCVS web interface allows on-the-fly generation of TAR balls from the current repository. Just click on the link Download tarball
  
• The old CVS repository has been switched to read-only and will be completely closed in a few weeks
  
• The machine midas.psi.ch will in the near future not be available any more for any repository
  
• All the $Log: tags in the midas files have been replaced by $Id: tags, since the former ones are not supported by SVN (for good reasons actually). To view the change log, do a svn log <filename>.
  

• Do not use the Cygwin subversion package, but the binaries from here if you plan to access the SVN repository through AFS at PSI (or other places where AFS is available). If you map the AFS repository for example to "Y:", then the binaries access this under file:///Y:/svn/meg/... whicl the cygwin ones access this under file:///cygwin/y/svn/meg/... While this is ok in principle, it gives a conflict with the TortoiseSVN which expects the first path. So if you want to use command line utilities together with TortoiseSVN, the Cygwin package won't work.
  
• Use the TortoiseSVN package. It's really great! It has a very nice "diff" viewer/merger, it's integrated into the Windows explorer, has a spell checker for composing comments for commits, etc.
  
• For the SVN binaries under Windows, you have to set the environment variable LANG=en_US, otherwise svn will talk in German to you on a standard PSI Windows PC.
  

Dear MIDAS users and developers,

The "Midas VME Standard API" has been revised. We tried to incorporate all
comments and ideas we got so far. The mvme_ioctl() function was abandoned in
favor of several mvme_get/set_xxx functions. Furthermore, two additional
functions for read and write have been implemented to simplify writing/reading
single values to VME. The current API looks like this:

int mvme_open(MVME_INTERFACE **vme, int index);
int mvme_close(MVME_INTERFACE *vme);
int mvme_sysreset(MVME_INTERFACE *vme);
int mvme_read(MVME_INTERFACE *vme, void *dst, mvme_addr_t vme_addr,
              mvme_size_t n_bytes);
DWORD mvme_read_value(MVME_INTERFACE *vme, mvme_addr_t vme_addr);
int mvme_write(MVME_INTERFACE *vme, mvme_addr_t vme_addr, void *src,
               mvme_size_t n_bytes);
int mvme_write_value(MVME_INTERFACE *vme, mvme_addr_t vme_addr, DWORD value);
int mvme_set_am(MVME_INTERFACE *vme, int am);
int mvme_get_am(MVME_INTERFACE *vme, int *am);
int mvme_set_dmode(MVME_INTERFACE *vme, int dmode);
int mvme_get_dmode(MVME_INTERFACE *vme, int *dmode);
int mvme_set_blt(MVME_INTERFACE *vme, int mode);
int mvme_get_blt(MVME_INTERFACE *vme, int *mode);

The MVME_INTERFACE structure holds all internal data, similar to the FILE
structure in stdio.h. If several VME interfaces (of the same type) are present
in a PC, the function mvme_open can be called once for each crate, specifying
the index. The block transfer modes passed to mvme_set_blt control the usage of
DMA, MBLT64 and so on. Not all interfaces might support all modes, in which case
mvme_set_blt should return MVME_UNSUPPORTED. Then it's up to the user code to
ignore this error or choose a different mode.

So far we have implemented drivers for the SIS3100, SBS617/SBS618 and VMIC
interfaces using this standard. It should be noted that the VMIC uses solely
memory mapped VME I/O, which is completely hidden in the VMIC MVMESTD driver.

We would like to encourage people to switch to the revised MVMESTD API wherever
possible. If new drivers for ADCs and TDCs for example are written using this
standard, groups with different VME interfaces can use them without modification.

Although the standard works now for three different interfaces, it might be that
new interfaces need slight additions. They should be identified as soon as
possible, in order to adapt the MVMESTD quickly and freeze the API soon.

Interrupts are not (yet) implemented in the MVMESTD, because most experiments
use polling anyhow. If there is a need for interrupts by someone, he should come
up quickly with this and make a proposal for implementation.

Commited to CVS is the preliminary driver for the Wiener CC-USB CAMAC interface.
The driver implements all the mcstd.h camac access functions, except for those
not supported by hardware (8-bit operations, interrupts) and a few esoteric
functions not implemented in any other camac driver. The driver uses the
musbstd.h library to access USB, also commited in preliminary form.

Affected files:
midas/Makefile (added musbstd.c to libmidas.{a,so})
include/musbstd.h, src/musbstd.c (preliminary USB access library)
drivers/bus/ccusb.{c,h}

Most of the CAMAC access functions have been tested (see comments in ccusb.c).
If you find errors and problems, please email me (olchansk@triumf.ca) or write
an elog reply to this elog message.

Missing is the documentation and finalization of USB access library.
Missing is conformity to some MIDAS coding conventions.

Enjoy,
K.O.

It turns out that the new priority sequencing of run state transitions had a
flaw: the frontends, the analyzer and the logger all registered at priority 500
and were invoked in essentially a random order. For example the frontend could
get a begin-run transition before the logger and so start sending data before
the logger opened the output file. Same for the analyzer and same for the end of
run. Also the sequencing for pause/resume run and begin/end run was different
when the two pairs ought to have identical sequencing.

I now commited changes to mana.c and mlogger.c changing their transition sequencing:

start and resume:
200 - logger (mlogger.c, no change)
300 - analyzer (mana.c, was 500)
500 - frontends (mfe.c, no change)

stop and pause:
500 - frontends (mfe.c, no change)
700 - analyzer (mana.c, was 500)
800 - mlogger (mlogger.c, was 500)

P.S. However, even after this change, the TRIUMF ISAC/Dragon experiment still
see an anomaly in the analyzer, where it receives data events after the
end-of-run transition.

K.O.

> It turns out that the new priority sequencing of run state transitions had a
> flaw: the frontends, the analyzer and the logger all registered at priority 500
> and were invoked in essentially a random order. For example the frontend could
> get a begin-run transition before the logger and so start sending data before
> the logger opened the output file. Same for the analyzer and same for the end of
> run. Also the sequencing for pause/resume run and begin/end run was different
> when the two pairs ought to have identical sequencing.
> 
> I now commited changes to mana.c and mlogger.c changing their transition sequencing:
> 
> start and resume:
> 200 - logger (mlogger.c, no change)
> 300 - analyzer (mana.c, was 500)
> 500 - frontends (mfe.c, no change)
> 
> stop and pause:
> 500 - frontends (mfe.c, no change)
> 700 - analyzer (mana.c, was 500)
> 800 - mlogger (mlogger.c, was 500)
> 
> P.S. However, even after this change, the TRIUMF ISAC/Dragon experiment still
> see an anomaly in the analyzer, where it receives data events after the
> end-of-run transition.
> 
> K.O.

Thanks for fixing that bug. It happend because during the implementatoin of the priority
sequencing we have up the pre/post tansition, which took care of the proper sequence
between the logger, frontend and analyzer. The way you modified the sequence is
absolutely correct. It is important to have >10 numbers "around" the frontends (like
450...550) in case one has an experiment with >10 frontends which need to make a
transition in a certain sequence (like the DANCE experiment in Los Alamos).

Minor Makefile changes:
- add "-m32" gcc flag to force 32-bit compilation on 64-bit Linux.
- do not link ybos.o into lazylogger and mdump.
K.O.

I have been plagued by ODB corruption when I run the analyzer for the first time
after setting up the new experiment. Some time ago, I traced this to
mana.c::book_ttree() and now I found and fixed the bug, fix now commited to
midas cvs. In book_ttree(), db_find("/Analyzer/Bank switches") was returning an
error and setting hkey to zero. Then we called db_open_record() with hkey==0,
which cased ODB corruption later on. The normal db_validate_hkey() did not catch
this because it considers hkey==0 to be valid (when most likely it is not). K.O.

I fixed some minor bit rot in the example experiment: a few minor Makefile
problems, make the analyzer use the current histogram creation macros, etc. I
also added startup and shutdown scripts. These will be documented as we work
through them with our Summer student. K.O.

I had to move strlcpy & strlcat into a separate file "strlcpy.c". A header file
"strlcpy.h" was added as well. This way one can omit the old HAVE_STRLCPY which
made life hard. The windows and linux makefiles were adjusted accordingly, but
for Max OS X there might be some fixes necessary which I could not test.

Current MIDAS versions nag me about setting the env.variable MIDASSYS to the
"midas installation directory", but I do not have one, so what should I set
MIDASSYS to? I checkout MIDAS from cvs into /home/olchansk/daq/midas, build it
there, run it from there. I never do "make install" (I am not "root" on every
machine; I am not the only MIDAS user on every machine). What should I set
MIDASSYS to? K.O.

> Current MIDAS versions nag me about setting the env.variable MIDASSYS to the
> "midas installation directory", but I do not have one, so what should I set
> MIDASSYS to? I checkout MIDAS from cvs into /home/olchansk/daq/midas, build it
> there, run it from there. I never do "make install" (I am not "root" on every
> machine; I am not the only MIDAS user on every machine). What should I set
> MIDASSYS to? K.O.

Then set it to /home/olchansk/daq/midas. The reason for MIDASSYS is the same as
for ROOTSYS. Having it allows other packages like ROME to access the Midas source
code, include files and libraries.

I'm getting segfaults in yb_any_file_rclose (closing a file opened with
yb_any_file_ropen with type MIDAS).

I think there are bugs with freeing from uninitialized pointers my.pmagta,
my.pyh, and my.pylrl (which are only set when opening a YBOS file).  These
should be set to NULL in yb_any_file_ropen (case MIDAS).  Likewise, the MIDAS
format pointers my.pmp and my.pmrd should be NULLed for YBOS opens. 

It might be wise to also initialize the pointers in the "my" structure to null.

--Donald              

> I'm getting segfaults in yb_any_file_rclose (closing a file opened with
> yb_any_file_ropen with type MIDAS).
> 
> I think there are bugs with freeing from uninitialized pointers my.pmagta,
> my.pyh, and my.pylrl (which are only set when opening a YBOS file).  These
> should be set to NULL in yb_any_file_ropen (case MIDAS).  Likewise, the MIDAS
> format pointers my.pmp and my.pmrd should be NULLed for YBOS opens. 
> 
> It might be wise to also initialize the pointers in the "my" structure to null.

Do you see this crash even after my fix to (another?) double free?

K.O.

Dear midas users,

I have changed the ODB dump format to XML. As you might know, the logger writes
a special begin-of-run event to the .mid file which includes an ASCII dump of
the ODB. The same at the end-of-run. To read these ODB dumps back in offline
analysis, this requires setting up a ODB just to read back these values. In
order to avoid this, we switched the format to XML instead of the old ASCII
format. That way ROME can read the ODB dump and extract individual values from
it without setting up a shared memory.

A similar thing has been made for the ODB dumps to separate .odb files, which
are controlled by "/Logger/ODB Dump" and "/Logger/ODB Dump file". If the dump
file has the extension .xml, the file is dumped in XML format as well.

All the XML functionality is implemented in the new mxml.c/h library, which has
been added to the distribution, and which can be used in other projects as well
(XML configuration of ROODY?). It has already been successfully implemented in
ROME, so ROME is no longer dependent on libxml.

- Stefan

> All the XML functionality is implemented in the new mxml.c/h library, which has
> been added to the distribution, and which can be used in other projects as well
> (XML configuration of ROODY?). It has already been successfully implemented in
> ROME, so ROME is no longer dependent on libxml.

Since mxml.c/h is used in several projects (midas, ROME, elog), I separated it's
CVS tree. So in order to compile midas from scratch, you have to check out midas
AND mxml like

cd ~
cvs -d :ext:cvs@midas.psi.ch:/usr/local/cvsroot checkout midas
cvs -d :ext:cvs@midas.psi.ch:/usr/local/cvsroot checkout mxml

cd midas
make

so the "mxml" tree is ABOVE the "midas" tree. The midas Makefile has been adjusted
accordingly. If you decide to put the mxml somwhere else, you have to change
MXML_DIR in the Makefile accordingly.

- Stefan

> > All the XML functionality is implemented in the new mxml.c/h library
> 
> mxml.c/h ... I separated it's CVS tree.
>
> The midas Makefile has been adjusted accordingly.

Looks like the midas mxml Makefile bits did not make it to CVS. Current Makefile
revision 1.67 does not have them and building midas from cvs sources fails because it
does not find mxml.h and mxml.c

K.O.

> Looks like the midas mxml Makefile bits did not make it to CVS. Current Makefile
> revision 1.67 does not have them and building midas from cvs sources fails because it
> does not find mxml.h and mxml.c

I forgot to commit the new Makefile, thanks for reminding me. Now it should be fine.

Dear Midas users,

may I kindly invite you present your work at the Real-Time 2005 Conference in
Stockholm, June 4-10. The conference deals with all kinds of real time
applications like DAQ, control systems etc. It is a small conference with no
paralles sessions, and with two interesting short courses. The deadline has been
prolonged until March 13, 2005. If you are interested, please register under

http://www.physto.se/RT2005/

Here is the official letter from the chairman:

=====================================================================
               14th IEEE-NPSS Real Time Conference 2005
                  Stockholm, Sweden, 4-10 June, 2005
              Conference web site: www.physto.se/RT2005/

**********************************************************************
*                                                                    *
*        ABSTRACT SUBMISSION PROLONGED! DEADLINE: March 13, 2005     *
*                                                                    *
**********************************************************************

Considering that the Real Time conference is a highly meritorious and
multidisciplinary conference with purely plenary sessions and that the
accepted papers may be submitted to a special issue of the IEEE
Transactions on Nuclear Science we would like to give more people the
opportunity to participate. Therefore we have organized the program so
that there is now more time for talks than at the RT2003 and we are
extending the abstract submission to March 13. We strongly encourage
you to participate!

Submit your abstract and a summary through the conference web site
"Abstract submission" link. Please, make sure that your colleagues know
about the conference and invite them.

I would also like to take this opportunity to announce the two short
courses we have organized for Sunday 5/6:

- "Gigabit Networking for Data Acquisition Systems - A practical
introduction"
  Artur Barczyk, CERN

- "System On Programmable Chip - A design tutorial"
  Marco Riccioli, Xilinx

Please find the abstracts and more information about the conference on
www.physto.se/RT2005/

Thank you if you have already submitted an abstract.

Richard Jacobsson
General Chairman, RT2005 Conference

Email: RT2005@cern.ch
Phone: +41-22-767 36 19
Fax:   +41-22-767 94 25
CERN Meyrin
1211 Geneva 23
Switzerland

We stumbled upon and fixed a "double free" bug in src/ybos.c causing crashes in
lazylogger writing .mid files in the FORMAT_MIDAS format (why does it use
ybos.c? Pierre says- for generic file i/o). Why this code had ever worked before
remains a mystery. K.O.

is there a reason why histograms are not saved after a replay?

   /* save histos if requested */
   if (out_info.histo_dump && clp.online) {
                              ^^^^^^^^^^

perhaps the && should be ||?

> is there a reason why histograms are not saved after a replay?
> 
>    /* save histos if requested */
>    if (out_info.histo_dump && clp.online) {
>                               ^^^^^^^^^^
> 
> perhaps the && should be ||?

The original reason for that is the for running online, you want some histos for
monitoring after each run. For running offline, you specify a root output file via
"-o xxx.root" which contains trees AND histos. So the histos would there be twice
if you remove the "clp.online" from above.

Having "-o xxx.root" is IMHO a cleaner way, since you might want to analyze a run
in different ways (like using different calibrations). So what you do is specify
different "-o cal00123.root", "-o final00123.root" and so on, while with the
mechanism in eor() you always get the same file name. So try using "-o xxx.root"
and see if that fits your needs.

With recent changes to mana.c, creation of user ROOT objects in the MIDAS
analyser has changed. Here is the new example code for creating ROOT objects
that are visible in ROODY and are saved into the histogram file.

1) in the "global" context (outside of any function)

#include <TH1D.h>
#include <TProfile.h>

static TH1D* gMyHist1 = 0;
static TProfile* gMyHist2 = 0;

2) In the analyzer "init" or "begin run" method, create the histogram:

//extern TFolder *gManaHistosFolder; // from midas.h
gMyHist1 = new TH1D("gMyHist1",...);
gMyHist2 = new TProfile("gMyHist2",...);
gManaHistosFolder->Add(gMyHist1);
gManaHistosFolder->Add(gMyHist2);

(note: this will produce an warning about "possible memory leak")

3) In the per-event method, fill the histograms

gMyHist1->Fill(x);
gMyHist2->Fill(x,y);

4) In the Makefile, where you compile the frontend, add "-DUSE_ROOT" right after
"-I$(ROOTSYS)/include"

K.O.

> (preliminary, untested. I will keep this updated as I get testing feedback)
> 
> With recent changes to mana.c, creation of user ROOT objects in the MIDAS
> analyser has changed. Here is the new example code for creating ROOT objects
> that are visible in ROODY and are saved into the histogram file.
> 
> 1) in the "global" context (outside of any function)
> 
> #include <TH1D.h>
> #include <TProfile.h>
> 
> static TH1D* gMyHist1 = 0;
> static TProfile* gMyHist2 = 0;
> 
> 2) In the analyzer "init" or "begin run" method, create the histogram:
> 
> //extern TFolder *gManaHistosFolder; // from midas.h
> gMyHist1 = new TH1D("gMyHist1",...);
> gMyHist2 = new TProfile("gMyHist2",...);
> gManaHistosFolder->Add(gMyHist1);
> gManaHistosFolder->Add(gMyHist2);
> 
> (note: this will produce an warning about "possible memory leak")
> 
> 3) In the per-event method, fill the histograms
> 
> gMyHist1->Fill(x);
> gMyHist2->Fill(x,y);
> 
> K.O.


the book functions provide a convenient place to check against object duplication
and memory leaks etc., and a place to ensure that consistent subfolders are being
used.  eg. a while back we decided that TCutGs should be in a "cuts" subfolder.

To extend the booking to TProfile is fairly easy.  In fact if you want to
use the simple constructor TProfile::TProfile (const char *, const char *, Int_t,
Axis_t, Axis_t), then you could infact just use h1_book<TProfile>.

It now seems to me that the names h1_book, h2_book, cut_book are all too long
and even more upsetting are inconsistent.  Some of them are templates (most) and
some are not.  Perhaps they should all be templates, and all have the same name.
The attached patch accomplishes this (without deleting the old names).  With this
patch you can now do

gMyHist1 = book<TProfile>( "gMyHist2",...);

New book templates are needed when you (1) wish to change the subfolder, or (2)
need to use a different argument list in the constructor.  If you need help with
this for the TProfile constructors which are different from TH1D constructors then
let me know.  They should be easy to do.

For TGraph at lot depends on how you want to initialise the data points.

The current h1_book() macros (and the previous example analyzer code) have an
odd persistency problem: for example, the user wants to change some histogram
limits, edits the h1_book() calls, rebuilds and restarts the analyzer, starts a
new run, and observes that all histograms are filled using the old limits, his
changes "did not take". The user panics, I get paged during the Holy Lunch Hour,
everybody is unhappy.

This is what I think happens:

1) analyzer starts
2) LoadRootHistgrams() loads old histograms from file
3) user code calls h1_book()
4) h1_book template in midas.h does this (roughly):
      hist = (TH1X *) gManaHistosFolder->FindObjectAny(name);
      if (hist == NULL) {
         hist = new TH1X(name, title, bins, min, max);
5) since the histogram already exists (loaded from the file, with the old
limits), the TH1X constructor is not called at all, new histogram limits are
utterly ignored.

A possible solution is to unconditionally create the ROOT objects, like I do in
the example code posted at http://dasdevpc.triumf.ca:9080/Midas/191. That code
produces an annoying warning from ROOT about possible memory leaks. This could
be fixed by adding a two liner to "find and delete" the object before it is
created, trippling the number of user code lines per histogram (find & delete,
then create). Highly ugly.

midas.h macros (h1_book & co) can be fixed by adding checks for histogram limits
and such, but I would much prefer a generic solution/convention that would work
for arbitrary ROOT objects without MIDAS-specific wrappers (think TProfile,
TGraph, etc...).

Any suggestions?

K.O.

> The current h1_book() macros (and the previous example analyzer code) have an
> odd persistency problem: for example, the user wants to change some histogram
> limits, edits the h1_book() calls, rebuilds and restarts the analyzer, starts a
> new run, and observes that all histograms are filled using the old limits, his
> changes "did not take". The user panics, I get paged during the Holy Lunch Hour,
> everybody is unhappy.
> 
> This is what I think happens:
> 
> 1) analyzer starts
> 2) LoadRootHistgrams() loads old histograms from file

I can't get onto cvs@midas.psi.ch right now
(cvs update
cvs@midas.psi.ch's password: 
Permission denied, please try again.)

but when I changed LoadRootHistograms a few days ago I left it as:

    } else if (obj->InheritsFrom( "TH1")) {

      // still don't know how to do TH1s

so h1_book() is creating the first and only copy of the histograms.
I am able to create new histogram limits.
I don't get the memory leak problems.

However I have seen the memory leak problems before, and they are real.
They must be dealt with either by (1) first deleteing the old histogram
or (2) ensuring that histogram names are unique in the whole application
(different modules/folders can not use the same histogram names).

I will return to this once I can do a cvs update for midas.

John.

> 3) user code calls h1_book()
> 4) h1_book template in midas.h does this (roughly):
>       hist = (TH1X *) gManaHistosFolder->FindObjectAny(name);
>       if (hist == NULL) {
>          hist = new TH1X(name, title, bins, min, max);
> 5) since the histogram already exists (loaded from the file, with the old
> limits), the TH1X constructor is not called at all, new histogram limits are
> utterly ignored.
> 
> A possible solution is to unconditionally create the ROOT objects, like I do in
> the example code posted at <a
href="http://dasdevpc.triumf.ca:9080/Midas/191">http://dasdevpc.triumf.ca:9080/Midas/191</a>.
That code
> produces an annoying warning from ROOT about possible memory leaks. This could
> be fixed by adding a two liner to "find and delete" the object before it is
> created, trippling the number of user code lines per histogram (find & delete,
> then create). Highly ugly.
> 
> midas.h macros (h1_book & co) can be fixed by adding checks for histogram limits
> and such, but I would much prefer a generic solution/convention that would work
> for arbitrary ROOT objects without MIDAS-specific wrappers (think TProfile,
> TGraph, etc...).
> 
> Any suggestions?
> 
> K.O.

> I can't get onto cvs@midas.psi.ch right now
> (cvs update
> cvs@midas.psi.ch's password: 
> Permission denied, please try again.)

I had to upgrade midas.psi.ch today with Scientific Linux 3.03. Most things are back to work, but
 I failed to do the anonymous CVS account. I have to wait for next week when the experts are
there. I will let you know when it's working again.

- Stefan

> > I can't get onto cvs@midas.psi.ch right now
> > (cvs update
> > cvs@midas.psi.ch's password: 
> > Permission denied, please try again.)

cvs@midas.psi.ch should be up and running again.

So now that cvs is reachable again I have confirmed that
the code segment
 
     } else if (obj->InheritsFrom( "TH1")) {
 
       // still don't know how to do TH1s

is indeed still present.
If you want me to look at this some more, you need to provide some code to exhibit the problem.

John.

> > The current h1_book() macros (and the previous example analyzer code) have an
> > odd persistency problem: for example, the user wants to change some histogram
> > limits, edits the h1_book() calls, rebuilds and restarts the analyzer, starts a
> > new run, and observes that all histograms are filled using the old limits, his
> > changes "did not take". The user panics, I get paged during the Holy Lunch Hour,
> > everybody is unhappy.
> > 
> > This is what I think happens:
> > 
> > 1) analyzer starts
> > 2) LoadRootHistgrams() loads old histograms from file
> 
> I can't get onto cvs@midas.psi.ch right now
> (cvs update
> cvs@midas.psi.ch's password: 
> Permission denied, please try again.)
> 
> but when I changed LoadRootHistograms a few days ago I left it as:
> 
>     } else if (obj->InheritsFrom( "TH1")) {
> 
>       // still don't know how to do TH1s
> 
> so h1_book() is creating the first and only copy of the histograms.
> I am able to create new histogram limits.
> I don't get the memory leak problems.
> 
> However I have seen the memory leak problems before, and they are real.
> They must be dealt with either by (1) first deleteing the old histogram
> or (2) ensuring that histogram names are unique in the whole application
> (different modules/folders can not use the same histogram names).
> 
> I will return to this once I can do a cvs update for midas.
> 
> John.
> 
> > 3) user code calls h1_book()
> > 4) h1_book template in midas.h does this (roughly):
> >       hist = (TH1X *) gManaHistosFolder->FindObjectAny(name);
> >       if (hist == NULL) {
> >          hist = new TH1X(name, title, bins, min, max);
> > 5) since the histogram already exists (loaded from the file, with the old
> > limits), the TH1X constructor is not called at all, new histogram limits are
> > utterly ignored.
> > 
> > A possible solution is to unconditionally create the ROOT objects, like I do in
> > the example code posted at <a
> href="<a
href="http://dasdevpc.triumf.ca:9080/Midas/191">http://dasdevpc.triumf.ca:9080/Midas/191</a>">http://dasdevpc.triumf.ca:9080/Midas/191"><a
href="http://dasdevpc.triumf.ca:9080/Midas/191</a>">http://dasdevpc.triumf.ca:9080/Midas/191</a></a></a>.
> That code
> > produces an annoying warning from ROOT about possible memory leaks. This could
> > be fixed by adding a two liner to "find and delete" the object before it is
> > created, trippling the number of user code lines per histogram (find & delete,
> > then create). Highly ugly.
> > 
> > midas.h macros (h1_book & co) can be fixed by adding checks for histogram limits
> > and such, but I would much prefer a generic solution/convention that would work
> > for arbitrary ROOT objects without MIDAS-specific wrappers (think TProfile,
> > TGraph, etc...).
> > 
> > Any suggestions?
> > 
> > K.O.

Dealing with the NaN's in the history system in the past week, a question came
up at PSI about how to deal with invalid history data.

Assume you have several devices going into one history equipment, and one device
has a problem, such that it cannot be read. In the past, the device driver
system returned zero, which was written to the history file. While this is ok in
some cases, it might not be in others, where zero is maybe a valid measurement.
Furthermore, it might confuse some regulations loops.

An alternative is to keep the last correctly measured value. As long as the
device has its problem, the value is kept. However, values are written to the
history system which might look like valid, although they are not. So what about
writing explicitly NaNs to the history system? For the display routine the NaNs
could be omitted, leaving blank regions where no valid measurement is available.
Or one could explicitly mare the region as invalid. Konstantin, do you know how
to write NaN explicitly to a float variable? And what do the others think about
these possibilities?

- Stefan

I preliminary implemented NaNs into the history system. It works such that if a
device driver returns a read error status, the class driver writes a NaN
(Not-a-Number) into the corresponding variable via the new function ss_nan(). The
"mhist" utility directly displays these as "nan" (Linux) or "-1.#IND00" under
Windows, indicating the error status. The history display via mhttpd just skips
these values (see elog:/1). I think this is better than showing just zero values,
because in most cases zero is a valid measurement and could confuse people.

Of course it is not enough just having "gaps" in the history display, so it's
important that the corresponding device driver issues an error message, which could
even trigger an alarm.

I have tested this under Windows, but only compiled under Linux. The only class
driver I modified so far is "multi.c". People should have a look, make some tests,
and let me know if this is a good thing, or if we should change it somehow.

- Stefan