The MASS is powered up and Turbina is running
(if enabled in cdimm.ini)
The only difference in v1.13 is that the software turns on the
power to the telescope and CCD at startup and then continues
as before. This might lead to problems if these devices need
some time to boot. This is something we have to work on.
After the startup of cdimm.exe, the program initializes
internal variables depending on the CCD (ST-5,ST-7) and the
telescope and prizm geometry.
Then it opens communications with the CCD (eg. turn-on the
cooling) and the telescope.
If the cdimm.ini:"auto-dimm" parameter is '1',
then the software immediately starts the AutoDIMM mode,
otherwise it awaits user input.
Note: The weather status is taken from the
File->Meteo menu as a proxy for the real weather
conditions and may be used by the operator as a simple
(1-click) way to stop observations and close the dome.
Once the AutoDimm mode is enabled the system should
work fully automatic executing the following tasks:
- If the dome is closed -
but the sun is below twilight altitude
AND the weather is ok
- wake up the telescope (if asleep)
- start the CCD cooling
- open the dome
- start observations
- If the dome is open -
but the sun is above twilight altitude
OR the weather is bad
- close the dome and stop observations
- put the telescope into sleep mode
- turn-off the CCD cooloing
- put the MASS into 'park' mode (if enabled)
- Select a star from the catalog. The algorithm considers
the brightness, airmass, azimuth, minimal zenith distance,
etc. and the number of previous rejections (star not found or
too faint) ... todo explain algorithm
- Move the telescope and center the star
- Take the MASS background measurement (if enabled)
- Start the DIMM measurement
- Start the MASS measurement (if enabled)
- Evaluate the focus after each exposure sequence and
adjust the focus if necessary
Detailed Program Flow
Program Initialization: (run once at startup)
- setup_constants() [cdimm.c]
{
- setup telescope geometry and CCD specific values
- set system_initialized = FALSE
}
- if (cdimm.ini:"auto-setup",default=yes) then
call setup_hardware() [cdimm.c] in background thread
{
- if (cdimm.ini:"dome-host",default=no) then
{
- power up telescope
- power up CCD
- check dome status
- check fan and lamp power status
} else {
- assume power to CCD and telsecope is ON
- assume dome is closed
- ignore (non-existent) fan and lamp
}
- initialize telescope [teledlg.c:do_tele_init()]
- todo show list of commands used
- initialize CCD [dacq.c:do_ccd_init()]
- todo explain details
- set system_initialized = TRUE
}
- create GUI
- set setup_stage = TRUE
- start Timer (2 seconds interval)
- enter Windows event loop
Timer Function: (called every 2 seconds)
- if (NOT system_initialized) then return
- if (setup_stage) then
- open Telescope, SkyMap and ObjectList windows
- if (cdimm.ini:"supervisor",default=no) then open sockets
- if (cdimm.ini:"auto-dimm",default=no) then
set auto_dimm = TRUE
- set setup_stage = FALSE
- if (lamp_power ON) then
- if (lamp on for more than 2 minutes) then turn off lamp
- if (telescope slewing) then
{
- if (telescope NOT stopped) then return
- set new object name
- calculate expected flux
- if (telescope and DIMM in auto-mode) then
{}
}
- if (do_mass_background() running) then
{}
- if (do_center() running) then
{
- if (centering NOT done) then return
- if (star NOT found) then
{
- set have_dimmstar = FALSE
- increment not_found counter for this star
(reduces likelyhood of this star to be selected again)
- increment global not_found counter
- if (not_found == 3) then set METEO==BAD and
suspend operations for 30 minutes
} else { }
}
- if (focussing) then
{
- if (do_tele_focus() NOT done) then return
- set focussing = FALSE
}
- if (dome_moving) then return
- if (centering) then return
- update zenith distance correction
- if (DIMM measurement running) then return
- if (MASS measurement running) then return
- update Moon and Sun positions
- if (new day) then change logfile name
todo explain state at some critical points
- if (AutoDIMM mode enabled) then
{
- if (dome NOT open) then
{
- if (sun_altitude below twilight AND
METEO == OK) then
{
- wake telescope: do_tele_init()
- wake CCD: do_ccd_init()
- set have_dimmstar = FALSE
- start open dome [dome.c]
}
} else { (dome is open)
- if (sun_altitude above twilight OR
METEO == BAD) then
{
- set have_dimmstar = FALSE
- sleep telescope, CCD and MASS
}
}
}
- if (dome NOT open) then return
- if (AutoDIMM mode NOT enabled) then return
- update Alt/Az of telescope
- if (telescope Auto mode enabled) then
{
- if (have_dimmstar == TRUE) then
{} else { (we have no dimm-star) }
}
- if () then
{}
- check Alt/Az
- telescope in auto-mode ?
- evaluate current star
- find new star ?
- focus in auto-mode ?
- check focus - move focus
- start DIMM measurement
- start MASS measurement
Time-stamp Counter
The Pentium class CPU has an instruction to read the current time-stamp counter
variable, which is a 64-bit variable, into registers (edx:eax).
The TSC (time stamp counter) is incremented every cpu tick (1/CPU_HZ). For example,
at 1GHz cpu, TSC is incremented by 10^9 per second.
It allows to measure time in an accurate fashion.
static __inline__ uint64_t rdtsc(void)
{ uint64_t rval;
__asm__
volatile ("rdtsc" : "=A" (rval));
return rval;
}
Christoph C. Birk (birk AT obs DOT carnegiescience DOT edu)
