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[cmosfreak]

Hi all,

let me open a separate topic besides the hand controller discussion:
Is it possible to modify the AstroEQ firmware to start at sidereal tracking rate immediately after powerup?
Let me explain a bit: Sometimes I'm using the mount for a simple "guiding" of my wide angle lenses. In this setup I don't want to use a PC/laptop at my observing location.

cs, Andreas

[TCWORLD]

Hi Andreas,

At the moment this is not possible directly. Basically EQMOD does some initialisation of the AstroEQ controller when it connects, routines needed to get the motors to be enabled (sort of a safety feature by not allowing the motors to run when EQMOD is not connected).

I am looking at making the firmware automatically enable the mount in a stand-alone mode, but I haven't decided the best way to do it. Either it will enable (if not already) whenever it detects a pulse on the ST4 port, which will then allow tracking and guiding to be performed without EQMOD. This would be the simplest way, but phantom pulses on the ST4 port could enable the mount unintentionally. Alternatively, on all of the AstroEQ's since hardware V4.3 have a GPIO port on the PCB (5-pin header between the PIC and ATMega), these are currently unused, and I may make it so that a switch connected to this can select between standalone mode (serial port disabled, auto-initialise mount), and PC mode (serial port enabled, don't auto-initialise mount). I think the latter would be the cleanest way of doing it from a software perspective, though it would require soldering on a switch to this header which may not be for everyone. Your thoughts?

I am working on some firmware improvements at the moment, and will integrate the changes for standalone once I know which of the two routes to go down. ETA on the new firmware is sometime in early January, once I've had a chance to test and verify everything.


In the meantime, there is a work around. If you open up EQMOD using the "EQMODLoad.vbs" script (just double click on it) in the "/bin/" folder of the AstroEQ config utility. Once EQMOD has to connected to the mount, set it in to sidereal tracking, then run the "EQMODQuit.vbs" script. This will get EQMOD to initialise the mount. Once disconnected, the mount will still be enabled and tracking, and also allow guiding with the ST4 port, even if you disconnect the USB cable (as long as you don't turn of the power).

[cmosfreak]

Hi Tom,

my favourite solution would be the additional switch for the two operating modes. I've built the PCB myself, so it's not really a problem to add the switch.
I guess, the only reliable way for the first proposal would be to add a "strong" pullup resistor <10k to the PCB. So, in both cases it's necessary to rework the hardware!?

Andreas

[TCWORLD]

That's what I was thinking. The internal pull-ups in the ATMega are OK, but they are between 30k and 60k.

I think the switch is the best idea, but even with that, I would still be relying on internal pull-ups for hardware which hasn't had the switch attached. But in this case at it is only 1 pin not 4 that I need to worry about, and it wouldn't be accidentally tripped by someone having an ST4 cable attached.

[Davis Patch]

Thank you for answers, for me it was informative.

[AL]

Hi Tom,

Is great to hear talking about standalone operation. It is what missing for me generally for visual use of my telescope without PC.

I have one more update to your idea. Using simple diy hand controller to change position of mount, 4 switches (4 directions) and best way when it will be connected to ST-4 port.

This needs one more GPIO switch to change ST-4 mode from classic rate 0.5x used for guinding to any faster rate (maybe programmed during configuration) for example x100. Especially to move object in center of view.

My old Losmandy Direct Drive System works similar. It was hand controller connected to built in ST4 port.

What do you think?

[TCWORLD]

Hi All,

I've been working on the idea, and have a plan. However some minor hardware modifications will be required for it to work.

Basically the standalone mode will require 6 pins. The four ST-4 pins will be used as direction inputs. Then on the GPIO header pins (for older versions wires can be soldered on to the board at the MCU socket), two will be used for control signals, one to enable standalone mode, and one to select the speed.

The standalone selection would need connecting to a switch which pulls the pin low (an optional pull-up resistor can be added though the internal ones will be enabled). When the pin is low standalone operation will be selected. When the pin is floating or pulled high, EQMOD mode is enabled.

The speed selection will basically give a choice between 2x Sidereal rate speed, and the Goto speed (set through the config utility). The 2x sidereal speed mode (pin being high or floating) will be adjusted to account for tracking - so for Dec. it will be 2x speed in both directions, but for RA it will be 1x speed for reverse and 3x speed for forward. When the RA is not being moved by the ST4 port, it will continue to track at the sidereal rate.

The ST4 port has 6 pins, but only 5 of them are wired up (N/C, GND, RA-, DC-, DC+, RA+). Pin 1 of the connector (currently unconnected) can be used for the speed control signal - so a jumper wire would be added on the PCB from the ST4 pin to the GPIO pin. This will allow a hand controller to be build which can be plugged in to the ST4 port with just a 6pin RJ11 cable. The switch to enable standalone mode would be placed on the AstroEQ enclosure.

I've finished adding the necessary code to the firmware, though have yet to test it. Any volunteers to test for me? I'll write some instructions for the required connections and post a hex file once I've done some further checks.

[bojan]

Hi Tom,
I just stumbled on this thread 
Yep, this is  exactly what I need.. well, almost (acceleration or at least much higher speed than 2x for positioning would be spot on.. perhaps 10-30x).
I plan to mount all necessary push-buttons on the electronics cover


I am willing and ready to test this functionality. Please let me know when you have code ready and where to get it from.
Thanks again!
Bojan

[TCWORLD]

Hi Bojan,

The plan is for two speeds, 2x for fine adjustments, and the go-to speed for positioning. The go-to speed is whatever speed you have set in the config utility.

I'll do some firmware tests tomorrow if I get a chance (or Monday otherwise), and then upload some notes on how to wire it up.

Tom.

[bojan]

Excellent, thank you!
Bojan

[bojan]

I was thinking... maybe you do not need any additional buttons (apart from obvious four on ST-4)?
The mode could be controlled by pressing one or more of the existing buttons during power up....

Then, the unwired pin on ST-4 connector could be used for 5V...

[cmosfreak]

Hi Tom,

do you have a first test version of the firmware for me with the new feature? I would need the source code version, because I've done some changes to the pinmap of the arduino and other changes.

Thank you!
Andreas

[TCWORLD]

Hi Andreas,

Sorry for the delay, got very busy the last week.

The firmware is changed, but I still need to do the testing I was going to do to make sure that it actually does anything. I'll try to do it tomorrow evening and let you know.

What I've done is to commit the current source code onto a new Github branch so you can download it. The development code is at: https://github.com/TCWORLD/AstroEQ/tree/v7.5-dev

Kind Regards,
Tom.

[TCWORLD]

In terms of connections, the following need to be made:

• gpioPin_1_Define = Stand-alone mode entry. This should have a switch selecting between GND and +5V (or floating as there is an internal pull-up).
• gpioPin_2_Define = Speed selection. This is recommend connecting to the spare pin on the ST-4 connector.

Shorting the entry pin to GND enters stand-alone mode. Floating or +5V means EQMOD mode.

The speed selection pin can be changed between GND and floating to select which speed is used. Floating means low speed. GND means high speed.

Connecting any of the ST4 pins to GND triggers the axis to move in that direction (note that if both say DEC+ and DEC- are pressed, then DEC+ takes priority). Floating means stop moving.

When neither RA button is pressed, the mount will track at the sidereal rate. When RA+ is pressed and in low speed mode, the mount will move at 3x the sidereal rate. When RA- is pressed and in low speed move, the mount will move at 1x the sidereal rate (in the opposite direction). The DEC+/- will cause that to move at 2x in either direction. Basically this means the movement speed is relative to the sidereal rate. With high-speed mode enabled, all axes will move at the go-to speed (which doesn't account for the sidereal rate).

The code is uploaded to the v7.5-dev branch on the repository. I'll attach some .hex files to this post once I've done a little testing and had a chance to compile them. Anyone who wants to test before that can download the source from Github.

[bojan]

Hi Tom,
those are excellent news!

I have a question: How to change the mode of operation on the fly? Or, what type of switches we should use, toggle or momentary?