So I'm starting a bit of an electronics project. I am going to call it "The All Things to All People" (TATAP) controller. My intention is to make this 100% open including software, circuit, PCB artwork and 3D model of the case if I end up going down the 3D printer route.
Simple criteria for my design:
1. Build it at home, parts of eBay or common electrical distributors and a PCB simple enough that it can etched at home.
2. As much as possible all in one box design.
3. Modular design. If someone wants to build it but doesn't need feature X then don't populate it.
Anyway this all came about after dragging to astrofest a power hub, usb hub, power monitor, dew heater, and losing power as well. Additionally I want to add a focuser at some point. All of these things were individually strapped to the tripod and there were cables everywhere.
Anyway currently I am planning the following feature list:- 12V power input
- 12V power monitoring (voltage and current)
- Piezo speaker
- Alarm for low voltage (for when running from batteries)
- 12V backup battery supply
- Trickle charger for backup battery
- Alarm for loss of primary supply (for running from 12V and backup battery)
- Multiple 12V outputs, relay switched.
- Multiple Dew heater controllers
- Temperature Sensor
- Humidity Sensor
- Autofocus stepper driver with temperature reporting (not compensation)
- External display and keypad for autofocus controller
- Everything fused with blade fuses
- All 12V inputs and outputs using secure connectors (leaning towards Anderson connectors instead of those crappy 12v plugs)
- A display and keypad to control everything
- Computer software to record and log everything
- Focuser will be compatible with the sgl_observatory open source ASCOM driver.
- USB hub will be in the case and powered from the device, but will be a separate product.
So any ideas of what else can fit in there or features you'd like to see if you want to build one too?
This will likely take me until Christmas or even after. Spare time is rare at the moment and the goal is to have it done well before the next winter season.
Additional Ideas + a dump of my brain to remember what to do:- Osc Prox switches for detecting mount position.
- Alarm inhibit via software (don't annoy the neighbours).
- USB master reset (via cutting data lines or via asserting reset on USB hub) More thinking needed since this approach would cause controller to drop out as well.
- Potential need to switch to ATMEGA328 as 8kb program memory may be too limiting.
- Dew controller to run autonomously or via computer, with computer allowing fancier dew control algorithms.
- Implement graphing / logging of temperature vs time (may help with dark library on non-temp-controlled CCDs)
- Labelling of I/O on computer display ala mounthubpro
- GPIO expansion header for unused pins. (low firmware memory cost)
- Analogue input expansion header for unused pins. (high firmware memory cost)
Progress Report:- Conceptual ideas still being worked through.
- Display, Humidity and Temp sensor tested.