Quote:
Originally Posted by plasticuser
The 328/quino can't do hundreds of things, run a graphical display well, lots tons of data then upload it to somewhere else or display it graphically.... The Atmel chips are great for embedded custom use, like if this were just going to be a dumb PWM controller, but they don't allow for so many options that a more capable board can do.
As for the voltage issue, a well regulated 3v3 supply is "clean" - the 12v supply in a car is not. It's noisy, prone to wide variation, just a plain old bad environment for delicate electronics, generally.
Why not find an Atmel-based project and posting constructively there, instead of criticizing and asking for justifications in a project that clearly isn't of interest to you?  |
Well it can do a graphical display correctly, it's done GLCDs before...
It can gather plenty of data for it's intended applications... and you can equip it with an SD Card for more storage.
The Atmel chips are indeed capable - PID PWM is about as controlled as you can get something, and they do this well...
Atmel chips want 5V typically - so how does 5V compare to 3v3? How do you propose to avoid the 12V in getting your 3v3 or 5V? I'm simply questioning your usage of clean 3v, compared to 12v and somehow applying this to the atmel chips.
I'm interested in the project, it was the reason why I opened it up in the first place, as I have my own Fan controller that I put together - it did not need to be fantastic, just on when I knew the thermostat was open and the car required cooling - no PWM needed or anything - and it was quick to setup.
I like the idea of making it better - hence why I looked at this thread, but I read through and find what amounts to rubbishing a perfectly capable microcontroller, and trying to adapt a ARM chip running linux to the application that is far more suited to the Atmel chips.
And of course, I read to find 12V labelled dirty, and 3v labelled clean, in an irrelevant context as in BOTH cases you must take 12V and regulate it down.
This then raises the question as to whether you have the ability and understanding to put this together and see it to fruition. Considering your dismissing a perfectly capable controller, and trying to adopt something else that isn't really suited (come on, 1Ghz and Video for what amounts to a MOSFET) - - I don't believe so!
I asked the questions to see if there was some element to your dismissing the ideal Atmel chips and see if what you are planning would make sense - and all I get is a go away, I don't know how to answer your questions with answers that fit.
What goes into selecting a controller?
Simple.. It's target application. You don't throw a new server at a user for web browsing. You give them a simple workstation. Same principle would apply here - give the application the intended chip it deserves, and don't complicate it to the point that it gets unworkable.
It's simple fan control - and you won't get far with the thermostat shut anyway.
After I went through my fan control - It turns out they rarely ever need to run - they run when idle, when I power up the AC, and when slow through traffic (I've got a light in my car telling me they are on so I know!). They rarely ever come on...
The controller that came with the car (faulty, so I made one to replace it) did speed control using MOSFETs - simple control too - temperature gets warm (above thermostat temp), and speed is not > x then it runs the fan proportionally faster. That was from Mitsubishi.
What your going on about is hardly what the application needs - the car is already warm when the thermostat opens, the fans need to modulate speed to reject enough heat to get that thermostat shut, and then stay off.
Clean, simple, no brains control. No need for thousands of logs, no need for any graphical display for it, small chip, a bit of a small circuit (go on, do that with the Raspberry PI!), and a bit of voltage regulation (which will be needed anyway).
Anyway, I'll let you waste your time, It's fairly clear to me that your trying to overcomplicate one of the most simplest of tasks.