battery powering issue Previous  1 ... 4, 5, 6, 7, 8, 9, 10  Next All
Author Message
 jgmdesign
 Posted: Jul 09, 2007 - 08:07 PM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 I said 7cm sq. draw a square 7x7 TA DA!! I will send you the photo though anyway Jim _________________Jim I have decided that I am no longer going to plan anything in advance. In a court of law this is called Pre-Meditated, and does not look good for the defense..... Timer function not working properly? Check CLKDIV8 Fuse first

 bloody-orc
 Posted: Jul 09, 2007 - 09:06 PM
 Joined: Dec 17, 2005 Posts: 1498 Location: Europe- Estonia- Tallinn
 7cm sq isn't 7cm x 7cm! Learn math! 7x7 is 49cm sq!

 jgmdesign
 Posted: Jul 09, 2007 - 09:21 PM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 Depends on what side of the pond you live on!!! HA HA ok ok ok, then the device is 7cm long x 7cm wide Jeez, whaddah grouch _________________Jim I have decided that I am no longer going to plan anything in advance. In a court of law this is called Pre-Meditated, and does not look good for the defense..... Timer function not working properly? Check CLKDIV8 Fuse first

 bloody-orc
 Posted: Jul 09, 2007 - 09:27 PM
 Joined: Dec 17, 2005 Posts: 1498 Location: Europe- Estonia- Tallinn
 I thought that was considered as a standard of some sort (SI maybe?) Oh well... another lesson learned. on both sides of the pond I hope

 barnacle
 Posted: Jul 10, 2007 - 09:50 AM
 Joined: Jan 03, 2006 Posts: 4417 Location: Hemel Hemsptead, UK
 Gentlemen, it's not a question of maths, it's a question of English usage... 7 cm square = 7cm*7cm = 49 square cm 7 square cm = 7cm*1cm = 3.5cm*2cm etc If the 'square' precedes the metric, then it's part of the unit that's being counted, so 7 (square cm) if you like. If the 'square' comes last them '7 cm' is what's being squared... it's easy to get them swapped around. Neil _________________Neil Barnes www.nailed-barnacle.co.uk

 jgmdesign
 Posted: Jul 10, 2007 - 12:56 PM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 Thanks Teach Jeez I suck at math _________________Jim I have decided that I am no longer going to plan anything in advance. In a court of law this is called Pre-Meditated, and does not look good for the defense..... Timer function not working properly? Check CLKDIV8 Fuse first

 mactom
 Posted: Jul 10, 2007 - 06:35 PM
 Joined: Jun 15, 2007 Posts: 110 Location: Gdańsk, Poland
 so how i understood the manner is 7 cm^2. seems like it's 7 times bigger than i thought. no way to put it on an arm, unless i really make myself a solar cell sweater. i already got my useless cell, and i got a thought. how about breaking the cell in half and joining those halfs in series? that SHOULD give me 1V instead of .5V, but with less amperage. does it sound logically? if that would work and my cell is actually producing current mentioned on the datasheet, i wouldn't need your cell anymore, Jim, but it's not a decision yet. thanks anyway for your help. _________________Not entirely familiar with AVR thingies... yet.

 jgmdesign
 Posted: Jul 10, 2007 - 08:57 PM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 I would love to watch you break the cell in half. Oh by the way, If you still are looking to make a wristwatch with a solar cell and some supercaps good fun then. You will probably get arrested on suspicion of terrorism. The thing would look like a bomb!! Jim _________________Jim I have decided that I am no longer going to plan anything in advance. In a court of law this is called Pre-Meditated, and does not look good for the defense..... Timer function not working properly? Check CLKDIV8 Fuse first

 mactom
 Posted: Jul 10, 2007 - 09:04 PM
 Joined: Jun 15, 2007 Posts: 110 Location: Gdańsk, Poland
 i just need to know if that's going to work. breaking the cell in half is not a problem, the one i got is less than 1mm thin. the supercaps i bought turned out to be... a bit bigger han i thought. each one is as big as 7 big coins sealed into one. guess i'll use this battery pack bloody-orc suggested. _________________Not entirely familiar with AVR thingies... yet.

 mactom
 Posted: Jul 11, 2007 - 03:00 AM
 Joined: Jun 15, 2007 Posts: 110 Location: Gdańsk, Poland
 ok, so to answer jim's request, and to make happy all you guys willing to help me, here is a quick features guide covering my project basic overview: a watch, named armwatch, because of its incredible size which doesn't matter until it fits one arm. to operate the watch no help of another arm is needed. also, a separate eeprom onboard containing images in suitable format which's content display is triggered by a button. everything solar-powered, so it must survive nights. possible lcd+avr on/off switch to save power at nights. hardware ideas: -using attiny or atmega, depending on i/o number and considering least power needed to operate -lcd, options ordered from most cool to least cool: *color lcd from nokia or other manufacturer *fancy graphic mono if color are unreadable without backlight -possibly backlight triggered by handshake, using trembler or accelerometer -external rct powering ideas: -solar cells charging battery/supercaps and powering circuit. preffered as small as possible. -using dc/dc step-up/down to stabilize power to 3.3V -i'm considering using additional emergency supercap keeping rtc chip exclusively powered. software ideas (please note i have't done any AVR programming yet): -avr is being put to sleep and is waken up by rtc each second. the lcd content is updated and avr puts itself back to sleep. using highest clock frequency so it is put back to sleep faster. avr also reacts for button call to show graphics and to turn on backlight temporarily. -or the same as above but running without sleep on dead slow clock frequency, like 32kHz (as long as it's possible with internal clock, otherwise the external one might be used, or rtc pulses) -due to my serious troubles at university, programming will be done in old pal basic instead of studying asm. stuff i already got: -Philips 8583T RTC -5x 5V 0.22F supercaps, but it turned out that they're huge, so don't expect me to use all of them not more than three -0.5V 70mA solar cell, currently figuring out how to boost voltage with current reduction. stuff i keep an eye on: -MSP-430SOLAR PANEL 2.4VDC 80mA with DC/DC voltage boost converter (posted by zauberer above) -http://www.oomipood.ee/index.php?t=k_ki&i=FARNELL_1319725 (lithum battery posted by bloody-orc) -Jim's solar cell, 49cm^2 so quite big. Quote: The cell produces 2.7vdc@3ma in flourescent light, and 3.6vdc@6ma in bright sun. current figuring out process results: -my solar cell gives too poor voltage, so how about splitting it into two pieces and joining them in series to get higher voltage and lower current? i've seen on auction a broken pieces of solar cells and the guy claimed it's working. -the same might be done with jim's cell to fit it my arm's size and power needs. but just please tell me if it's realistic at all. -while using my poor cell no step-down will be needed; although if i wanted to use jim's, both step-up and down features would be essential because his cell is exceeding 3.3V rate. phew, i guess that's it. (added few minutes later) my 66th post. it makes 2/3 of satan's number, isn't it? _________________Not entirely familiar with AVR thingies... yet.

 jgmdesign
 Posted: Jul 11, 2007 - 01:00 PM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York

 mactom
 Posted: Jul 11, 2007 - 07:55 PM
 Joined: Jun 15, 2007 Posts: 110 Location: Gdańsk, Poland
 thanks, master. i think i'll sketch it after couple of lessons of circuit theory i need to learn for september anyway. wash and go, that's what i like. not to offend you but you seem to be quite sane for me in the meantime i'll seek for an lcd in gsm sevices. the solar cell parametres is what i've read in datasheet, never checked it myself. but i will. what do you exactly mean by dropping RTC? what do you suggest to use instead? i've noticed that running atmel all the time is pretty hard to power. both our cats love rubbing their faces and ears, but after castration both turned into sort of... gay? they prefer scratching just next to their tails now. i'd rather do some girl's task than THIS, like washing up. _________________Not entirely familiar with AVR thingies... yet.

 bloody-orc
 Posted: Jul 11, 2007 - 08:34 PM
 Joined: Dec 17, 2005 Posts: 1498 Location: Europe- Estonia- Tallinn
 you can run the AVR from 32,768kHz. or at least the timer (some chips can have 2 crystals connected to them. one for processor clock and the other one for timer.) Get yourself a good big chip; I don't think you can do it all with just 8 pins. I was thinking of tiny26L or something similar (although it doesn't have the ability to use 2 crystals AFAIK). anyway good luck with your clock, LCD and gay(?) cats.

 jgmdesign
 Posted: Jul 11, 2007 - 11:34 PM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 Mactom, You will not need the RTC. TRUST ME. Just do your (4) homework items and then we move on. I will give you one hint: Look at the specs on the Tiny micros running at 32khz. The cats are not gay, but I can understand them being pissed off at you for having their 'nad's sliced off. Remember, one step at a time dude _________________Jim I have decided that I am no longer going to plan anything in advance. In a court of law this is called Pre-Meditated, and does not look good for the defense..... Timer function not working properly? Check CLKDIV8 Fuse first

 jgmdesign
 Posted: Jul 12, 2007 - 12:30 AM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 Here is the solar cell everyone want's to see!!!

 mactom
 Posted: Jul 12, 2007 - 02:24 AM
 Joined: Jun 15, 2007 Posts: 110 Location: Gdańsk, Poland
 the picture is not a surprise when we know the dimentions already, but compared to this avr its... bigger! well, Jim's right, the topic should be more about powering right now, so let's put chips and crystals aside, at least until i start a new thread in projects room. _________________Not entirely familiar with AVR thingies... yet.

 jgmdesign
 Posted: Jul 12, 2007 - 04:31 AM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 Mactom My homework has everything to do with powering!! How do you design a power supply if you do not know what the requirements of it are? In other words, you need to select the micro, display etc. first. Then work on the power supply, then look at both and see if everything is what you are looking for and adjust accordingly. You answered task 4 in the homework, now do the first three You will notice I did not include the power supply in the three things Jim _________________Jim I have decided that I am no longer going to plan anything in advance. In a court of law this is called Pre-Meditated, and does not look good for the defense..... Timer function not working properly? Check CLKDIV8 Fuse first

 jgmdesign
 Posted: Jul 13, 2007 - 10:04 PM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 Mactom: How are you making out with your schematic and component selections? Jim _________________Jim I have decided that I am no longer going to plan anything in advance. In a court of law this is called Pre-Meditated, and does not look good for the defense..... Timer function not working properly? Check CLKDIV8 Fuse first

 mactom
 Posted: Jul 13, 2007 - 11:08 PM
 Joined: Jun 15, 2007 Posts: 110 Location: Gdańsk, Poland
 easy, jim, haven't found an lcd yet, so it's a trick to pick suitable uC. tell me, how much i/os will i need? seems like nokia lcds have command input, command/data switch and clock input. moreover, one button, possibly an accelerometer, and eeprom on some ios are making 6 or more of them necessary overall. is there something wrong? _________________Not entirely familiar with AVR thingies... yet.

 jgmdesign
 Posted: Jul 15, 2007 - 07:52 PM
 Joined: Apr 20, 2007 Posts: 6079 Location: Long Island New York
 Don't know what you mean by is there something wrong. The lcd is your first area thaat needs to be resolved, then the micro. I cannot tell you how much I/o you will need as I do not have a parts list that you want to use. you are doing well. Pick the display first and see what is needed to run it. Feel free to tell me the part numbers and I can look them up and see where you are going Jim _________________Jim I have decided that I am no longer going to plan anything in advance. In a court of law this is called Pre-Meditated, and does not look good for the defense..... Timer function not working properly? Check CLKDIV8 Fuse first

 Display posts from previous:  All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First
 Jump to: Select a forum Forum index|--[AVR (8-bit) Technical Forums]|   |-- AVR forum|   |-- XMEGA forum|   |-- AVR Wireless forum|   |-- AVR GCC forum|   |-- AVR Studio 5 and Atmel Studio 6 forum|   |-- AVR studio 4 forum|   |-- AVRfreaks Academy forum|   |-- AVR Tutorials|--[AVR Software Framework]|   |-- AVR Software Framework|--[AVR32 (32-bit) Technical Forums]|   |-- AVR32 Linux Forum|   |-- AVR32 General (standalone)|   |-- AVR32 Software Tools|   |-- AVR32 Hardware|--[General Electronics Technical Forums]|   |-- General Electronics|   |-- Atmel Security Products|--[Non-technical forums]|   |-- AVRfreaks.net Housekeeping|--[Non-topical forums]|   |-- Off-topic forum|   |-- AVRfreaks Trading Post
All times are GMT + 1 Hour