@gaetan mentioned his driver can work without moding the cam (at least that's my understanding), so I ported his changes to the current driver and recompiled but despite I can load the new module with appropriate settings (flashled=1) I still get an error when clicking on the "SPC900 LED" button in the "Long Exposure" tab of the indi_v4l2_ccd panel:
2020-08-05T14:24:30: Can not set Lx Mode to SPC900 LED
2020-08-05T14:24:30: ERROR: device does not support PWC ioctl
Anyone know how to shoot long exposure frames with the SPC900? Is there any solution which doesn't involve soldering and buying more electronic parts?
You need a modded camera to control the long exposure (it sets a specific pin available on the internal connector of the cam).
Usually the control of the long exposure pin is made through a serial port (RTS if I remember) and this adds another cable in addtion to the USB camera port.
The LXLED mod consists in unsoldering the led on the board and using that wire to control the long exposure pin. And the LXLED also needs a modded version
of the pwc kernel driver (which does not expose the LED control).
Thus unfortunately, you would have to mod the cam if you want to use it with long exposure.
Last point concerning the error message: it seems you did not use the modded kernel driver when you made your test: at least you should be able to turn off the led if you do not have a modded camera
As has been said, it will not work without the actual long exposure mod, so you have been misinformed.... it requires some skilful soldering work to do the mod....
Stellarmate OS on Raspberry pi4b
Skywatcher EQ8 pro, on steel pier
Takahashi FSQ85 & Meade 8” SCT (de-forked)
Starlight Xpress SXVR H18, SXVR M25c, Lodestar x2 Guide Camera
Pegasus Ultimate Hub V2 for all USB & Power
Pegasus focus motors on both scopes