Dear Howard,

I have some questions about Focuser interface.

1) Is there an objective reason to chose a relative range like the default -25 .. + 25 instead of and absolute one 0 .. 50 ?
     By the way when using a relative range the two commands :FZ# and :FH# have the same result, both return to half track.

2) Is the :Fp# command the way to indentify whether a DC or Stepper Focuser is present?

3) I loaded yesterday 1.20.b firmware and noticed that the following commands not anymore have effect :FF#   :FS#  :Fn#, did anybody else notice this?

4) whould it be possible to implement the following (part of Indi Model)  for the focuser interface?

1. SyncFocuser  syncing the focuser to any arbitrary position withing the stroke range
2. SetFocuserSpeed   by providing a value for example 0 .. 100%
3. ReverseFocuser  by providing a 1/0 for enable / disable

The reason for all my questions is related to the way Indi treats focuser (considering only positive travel).

hereunder my configuration for the focuser (platform MaxPCB):
==============================
// FOCUSER1 ---------------------------------------------------------------------------------------------------------------
// Pins 34,35 = Step,Dir
#define FOCUSER1_ON                                      // use _ON to enable this focuser, default=_OFF
#define MaxRateAxis4                         3              // this is the minimum number of milli-seconds between steps, default=8.  In DC motor mode PWM frequency.
#define StepsPerMicrometerAxis4       1.225       // figure this out by testing or other means.
#define MinAxis4                                  0             // minimum allowed position in millimeters, default = -25.0
#define MaxAxis4                               38.0          // maximum allowed position in millimeters, default =  25.0
#define AXIS4_REVERSE_ON                            // reverse the direction of focuser movement.
#define AXIS4_DISABLE_OFF                            // Pin A22 (Aux6.)  Default _OFF, use HIGH for common stepper drivers.
#define AXIS4_AUTO_POWER_DOWN_OFF     // use _ON if you want to power down the motor at stand-still.  Default _OFF.  Ignored in DC motor mode.
#define AXIS4_DC_MODE_OFF                         // enable DC focuser instead of a stepper motor.  Automatically uses Phase 1 if enabled.  Default _OFF.
=======================================

Thank you for your help

On Wed, Feb 20, 2019 at 01:16 AM, alain wrote:

1) Is there an objective reason to chose a relative range like the default -25 .. + 25 instead of and absolute one 0 .. 50 ?

The first implementation didn't have the ability to store the current position in EEPROM so using zero had a certain elegance to it.

     By the way when using a relative range the two commands :FZ# and :FH# have the same result, both return to half track.

I doubt that's true, with the default Min/Max yes but not always I think since :FH# sets: ((MaxAxis4+MinAxis4)/2.0)*1000.0 microns.

2) Is the :Fp# command the way to indentify whether a DC or Stepper Focuser is present?

Yes.

3) I loaded yesterday 1.20.b firmware and noticed that the following commands not anymore have effect :FF#   :FS#  :Fn#, did anybody else notice this?

Just checked 1.20.b focusing in the web-interface, which uses :FF# and :FS#, and it works fine for me.

4) whould it be possible to implement the following (part of Indi Model)  for the focuser interface?

1. SyncFocuser  syncing the focuser to any arbitrary position withing the stroke range
2. SetFocuserSpeed   by providing a value for example 0 .. 100%
3. ReverseFocuser  by providing a 1/0 for enable / disable
4.  

I suppose I can take a look at adding those.

1.  

It might be a little while for this since I'll probably promote the Alpha to Beta first.

Howard,
Never mind!

I will look at the code and come to you with a proposal.

Thanks