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  1. If you are not getting all the formating abilities of printf/scanf, I can't see a reason to implement them, you can just write your own routines preferably with a circular buffer implementation(I just skimmed the text but as I understand, Michael Barr says this.) and name them whatever you like. But if the reason for wanting printf is formating purposes than you should go as Harman says. If you ask my opinion: printf/scanf formatting is not so suitable for uart, I did write my own routines in the past with support for different configurations(by implementing handlers) and advanced formating with start and stop frames and such.
  2. Can I ask for a simple circuit diagram for interfacing msp430 with a heater that runs off from mains(220Vac here, to be more specific.) Or a pointer to a reliable source will be appreciated as much, since there are so many different things on the internet and I lack the experience on this topic to decide.
  3. I don't, and I am not expecting the answer to be long I actually never measured how much current do I need and assumed much, and SSR s with much load current are pretty expensive, but it seems like i should measure my load asap
  4. This thread was left alone for a while because i was i little more busy than i expected but here are what i did on the time passed: 1-) I gave up from fancy but unnecessary stuff like touch lcd(whats bad about character lcds and 2 buttons ), so i ditched 5XXX series and started designing a board with F2274, i almost finished it and hopefully post it soon to hear what everyone thinks. 2-) I also decided not to use a dimmer circuit because since the system response is so slow that won't really provide any real advantage. Instead i will just use a relay to open and close the controller with low frequency pwm(somewhere about 1hz). At that point i will point a question: I am driving the relay with an npn transistor and a diode, standard stuff but I wonder if i will need a optocoupler to prevent mains wreaking havoc in my precious circuit. I can't understand the power-electronics stuff but since my load is resistive i think i won't need an optocoupler but I want to hear opinions. Also i will want an optocoupler recommendation to use on my board, since I never used those little buggers. Thats all for now, seems like I will be starting on my software soon. Also thanks to everyone contributed to and will contribute to thread. Edit: I wanted to add that relay circuit and controller will be on seperate boards/enclosures but they will be connected electrically anyway.
  5. You can solder it with a fine tip iron, its not as hard as it seems, if not you might try to get a lqfp zif socket but those guys are a little hard to get where i live.
  6. First of all, be very careful, you are dealing here with high voltage, make sure your circuit is properly grounded and isolated. Dimmer circuit will be perfect for the heater. I would use opto-triac to control power triac, because opto-triacs will isolate your circuit and usually come with built-in zero crossing detector, one less thing to worry about. Usually, circuits like this get their Vcc from line power, lowering it using a resistor and zener or regulator. Since you want to do some fancy stuff like USB connection, separate supply is the way to go. You can probably pick up cheap 5V regulated supply or salvage one from an old phone or something, or get unregulated one and just add a 5V or 3.3V regulator (http://www.sparkfun.com/products/526) Thanks for the answer, I think I'm going to use an old cellphone adapter. And insert the glcd later since its a tad bit on the expensive side.
  7. I am planning to build a msp430 based water temperature controller to test my wits in control theory, and wanted to share my design with you guys to and learn what you are thinking about it. I actually don't have any problems in the control theory or software side, but the power side is making me worry since i have absolutely o experience in power electronics .Below is my functional diagram, i want it to be pretty awesome so i added a lot of unnecessary functionality to it, like touch lcd to configure target temp. and control coefficients on the fly, usb connection to connect it to a desktop app. i wrote or possibly MATLAB, vibration motor to circulate the water for even heating and yada yada yada. And if we come to questions in my head: 1) I plan to use a bigger msp430, possible msp430f5xxx series to be able to implement all the features i want and leave room for future extensions. I think i can use my Launchpad to flash and debug a msp430f5xxx that supports spybiwire, am I correct? 2) I looked but failed to find a reference design for a barebones msp430f5xxx circuit, i'm thinking about looking at the circuit diagrams of development boards, but i want to know if there is a document about it that i couldn't find. 3) I'm planning to use a 220V AC Heater(which i will probably salvage from an electric kettle), and to control it, create a dimmer circuit since the load will be resistive it won't create any problems, am i right? 4) I will probably get all my power from a wall plug, will you recommend any converter to power all the non-heater parts(500-600 mAmps will be enough i guess.), preferably something not too expensive and i can buy. I don't want to fiddle a lot with power, I am an electronics guy, beyond 12 volts is beyond my interest. I will of course keep the community informed about my process, i expect to finish it in 4-5 weeks maybe a little longer.
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