The Max Output voltage is 10V based on the components Dave has chosen.
We will need more PIN's, there is a need for a bigger micro, this means no arduino compatibility(maybe mega).
I'm going to buy one of the kits however Dave develops it.
A fan controller can be done off-board easily enough. To be honest, given the target client base for this project, i dont believe making a port available to a 8 pin header is a major change. My keypad idea was for my own use. It makes the kit more flexible for end users.
Code is easily adapted for users own setups according to there mods if the mcu is Arduino compatible.
I believe this design change would make this a very attractive kit. Given its ability to be customized via the available port and being able to select he screen back color. The back color can be set to change to indicate different conditions for example.
This is just an idea.
Regards
The Max Output voltage is 10V based on the components Dave has chosen.
- MAX4080 76V
- LT3080 36V
- LM334 40V
- LM78M05 35V (actually, I don't think this is a good idea if this 5V is also provided on an USB connector, only 0.5amps)
- NJM14558 14V but this one is easily changed to something else, like powered by an 78L12 (35Vin)
- IRLU8721 gate 20V same 78L12
- missed anything?[/il]
now while i hate to make a redundant post
...
Sorry. I meant based on the gain resistors on the OpAmps, and voltage dividers, etc. His design is 10V max, you can change component values (gain resistors, etc) to get more.
and just for those that have yet to see part 6's video, the lt3080 seems pretty much indestructable to reverse voltage, as long as you dont short the input,
i dont believe it was, but it was pretty much just a test to see what the reg could survive,
really if the rest of the circuit was left connected, the op amps and adc would have fried well before the diode,
still i am now content and awaiting the next update, (think daves board is still being held hostage by aus post)
AFAIK all Arduino compatible Ethernet variants use the Wiznet W5100 chip which is fine pitch SMD.
Hardly suitable for a DIY kit.
Dave.
For those who wanted an Arduino header footprint on the board, I've looking into this.
I'm not sure what that means, Dave. If you check out this page you will see that there are many variations on the Arduino hardware:
http://arduino.cc/en/Main/Hardware
For example, the Arduino Mini comes in a very small package, including crystal. Or you might choose the Pro Mini.
For me, the "Arduino compatibility" is simply using an Atmega168/328 or similar chip, and preferably being able to program it "in situ" which means you don't turn off the functionality of the reset pin. Although even with that dedicated to driving an LED, you can probably program it with careful timing (ie. using power-on reset).
If you are reworking the processor part, I would free up the reset pin for resetting, and do something along the lines of my earlier suggestion for interfacing with the switches. You can probably save yourself some pain by choosing I2C compatible chips (like the DAC and ADC) rather than mixing SPI and I2C. After all, I2C can address 119 chips. That frees up more pins again.
Indeed, for polling the front panel switches, a simple I2C port-expander could handle that, allowing something like 8 switches and 8 LEDs, all off one I2C part. (And port-expanders can generate interrupts, so you don't even have to poll them).
There are some people who have suggested that I add Arduino Shield headers connectors to the board.
That would be pointless without freeing up most of the pins.