Post by thread:[PIC]: IR remote control with a PIC, wake-on-rb-ch

Hello, We're wanting to make our own remote control for using with our products. So, I'm doing some experiments with wake-on-rb-change, learning remotes etc. One thing that is bothering me is how to make the power supply of a remote control. An ideal supply would draw zero miliamps from the battery when the PIC is sleeping. I could do the supply simply using a battery and a 78L05, but the regulator would draw some energy from the battery even without the microcontroller. Any sugestion? Someone have the squematics of a remote control using a PIC? Thank you very much, Brusque ----------------------------------------------------------------- Edson Brusque C.I.Tronics Lighting Designers Ltda Research and Development Blumenau - SC - Brazil Say NO to HTML mail http://www.citronics.com.br ----------------------------------------------------------------- -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email spam_OUTlistservTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body

Why use a regulator? Why not just a battery supply within PIC Vdd range? Dale -- "Curiosity is the very basis of education and if you tell me that curiosity killed the cat, I say only the cat died nobly." - Arnold Edinborough On Sat, 3 Aug 2002, Edson Brusque (Listas) wrote: > One thing that is bothering me is how to make the power supply of a > remote control. An ideal supply would draw zero miliamps from the battery > when the PIC is sleeping. I could do the supply simply using a battery and a > 78L05, but the regulator would draw some energy from the battery even > without the microcontroller. -- http://www.piclist.com hint: To leave the PICList .....piclist-unsubscribe-requestKILLspam@spam@mitvma.mit.edu

> One thing that is bothering me is how to make the power supply of a > remote control. An ideal supply would draw zero miliamps from the battery > when the PIC is sleeping. I could do the supply simply using a battery and a > 78L05, but the regulator would draw some energy from the battery even > without the microcontroller. You can get "L" version PICs that run on a supply from 2V to 5.5V. You don't need a regulator as long as you can guarantee your battery can't exceed 5.5V and 2V is essentially dead. 3x AAA cells, for example. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com hint: To leave the PICList piclist-unsubscribe-requestKILLspammitvma.mit.edu

Hello Olin, > You can get "L" version PICs that run on a supply from 2V to 5.5V. You > don't need a regulator as long as you can guarantee your battery can't > exceed 5.5V and 2V is essentially dead. 3x AAA cells, for example. mmm, I'm seeing at the 16F628 (the PIC I pretend to use) that it can work @0-10MHz from 3V to 5.5V maybe I could make it with 3xAA cells and without a regulator. I will use two or three infrared LEDs and maybe they can't work bellow 3V. Another thing is that I'm hopping to put some learning capabilities on it and all the more common IR receiver modules (that 3 pin thing that resembles a transistor) seens to work from 3 to 5V IIRC. Thank you, I think I'll let that 78L05 go. Best regards, Brusque ----------------------------------------------------------------- Edson Brusque C.I.Tronics Lighting Designers Ltda Research and Development Blumenau - SC - Brazil Say NO to HTML mail http://www.citronics.com.br ----------------------------------------------------------------- -- http://www.piclist.com hint: To leave the PICList .....piclist-unsubscribe-requestKILLspam.....mitvma.mit.edu

Edson, Have the second pole of all your buttons goto an 2 input or gate. and the output of the or goto the pic power pin (you'll have to make sure it handle you pic's current load or you'll have to put some sort of driver behind it). The other input goes to a pic i/o pin. When a button is pressed it will turn your pic on via the or gate. Your pic then changes the line going to the or gate high, so if the user releases the button before your pic is done it keeps power to itself. When it's done set the line low and it will lose power. Come to think you could use a s/r flip flop (all buttons to s) it would probably be more reliable and when you wanted to turn off the pic you could set r high. Just be sure to get a good low power s/r flipflop. Aaron -- http://www.piclist.com hint: To leave the PICList EraseMEpiclist-unsubscribe-requestspam_OUTTakeThisOuTmitvma.mit.edu

There is a design for self switched PIC here: http://www.romanblack.com/self_swi.htm uses one cheap tiny (TO-92) SCR, and 2 resistors, will work with a 7805 reg or just with the battery and the PIC. :o) -Roman A.J. Tufgar wrote: {Quote hidden}> > Edson, > Have the second pole of all your buttons goto an 2 input or gate. > and the output of the or goto the pic power pin (you'll have to make > sure it handle you pic's current load or you'll have to put some sort > of driver behind it). The other input goes to a pic i/o pin. > > When a button is pressed it will turn your pic on via the or gate. > Your pic then changes the line going to the or gate high, so if the > user releases the button before your pic is done it keeps power to > itself. When it's done set the line low and it will lose power. -- http://www.piclist.com hint: To leave the PICList piclist-unsubscribe-requestspam_OUTmitvma.mit.edu

Hello Roman, > There is a design for self switched PIC here: > http://www.romanblack.com/self_swi.htm as always, your design is very smart, congratulations. Maybe I'll use it. The only think I don't like is that your web pages don't show very well with Opera and I'll have to use IE (argh). :^) I'll do some measurings and will try to find a little SCR on our local components shop. Thank you very much, Brusque ----------------------------------------------------------------- Edson Brusque C.I.Tronics Lighting Designers Ltda Research and Development Blumenau - SC - Brazil Say NO to HTML mail http://www.citronics.com.br ----------------------------------------------------------------- -- http://www.piclist.com hint: To leave the PICList @spam@piclist-unsubscribe-requestKILLspammitvma.mit.edu

Hello, I'm making some measurements and I've found some interesting numbers. When sleeping, the PIC16F628@4MHz consumes about 42uA @ 5V. If I suply it with some AA Alkaline batteries, it would mean rougly: 2850mAh / 42uA = 67857 hours = 2827 days = 7.74 years without use. This is very good! When not sleeping, whe PIC consumes about 1mA: 2850mAh / 1mA = 2850 hours = 118 days = 3.95 months with continuous use. Obviously, we have the Infrared LEDs, that can consume average about 3 mA (considering duty cycles and pauses between packets). 2850mAh / (1+3)mA = 712.5 hours = 29,68 days with continuous use. This is very good figures, and this means that a 78L05 is a complete waste of power. A 78L05 draws about 3mA when nothing is connected to it's outputs. So, 3xAA batteries would be a very better option as a 16F628 can work untill the batteries go down to 3V. When I'll put this on production, I'll buy the 16LF628 that can work down to 2V. Thank you all for pointing me to the right direction. Best regards, Brusque ----------------------------------------------------------------- Edson Brusque C.I.Tronics Lighting Designers Ltda Research and Development Blumenau - SC - Brazil Say NO to HTML mail http://www.citronics.com.br ----------------------------------------------------------------- -- http://www.piclist.com hint: To leave the PICList KILLspampiclist-unsubscribe-requestKILLspammitvma.mit.edu

> When sleeping, the PIC16F628@4MHz consumes about 42uA @ 5V. If I suply > it with some AA Alkaline batteries, it would mean rougly: > 2850mAh / 42uA = 67857 hours = 2827 days = 7.74 years without use. I know that this was only a calculation to determine how heavy the load was compared to the battery's capacity but do note that an Alkaline battery has a shelf life of around 3 years (some manufacturers claim longer). If you produce equipment with very low current drains then the reduction in battery capacity with time can make serious inroads into the actual operating time. When that happens, Lithium batteries are a possible solution. In this particular case it's not an issue as your expected operating lifetime is far shorter. If a regulator IS required there are much lower quiescent current drain versions than the 7805. For example the beautiful (but excessively expensive) LM2936 draws about 20 uA with no load in real world use and others draw even less. Turning the processor off completely can also be useful in some applications - eliminating the 42 uA off current MAY allow you to use smaller batteries (but PLEASE don't use AAA's :-) ) and a more compact design in some applications. As long as the startup time is quick enough for your application you can achieve true zero current when off. There are ICs that do this for you but you can achieve the same result with 2 (maybe 1) transistors. Russell McMahon -- http://www.piclist.com hint: To leave the PICList RemoveMEpiclist-unsubscribe-requestTakeThisOuTmitvma.mit.edu

Hello Russel, > If a regulator IS required there are much lower quiescent current drain > versions than the 7805. For example the beautiful (but excessively > expensive) LM2936 draws about 20 uA with no load in real world use and > others draw even less. Thomas McGahee sugested a LDO circuit four months ago. It's not very simple, but it could be made very cheap for low current applications. > Turning the processor off completely can also be useful in some > applications - eliminating the 42 uA off current MAY allow you to use > smaller batteries (but PLEASE don't use AAA's :-) ) and a more compact > design in some applications. As long as the startup time is quick enough for > your application you can achieve true zero current when off. There are ICs > that do this for you but you can achieve the same result with 2 (maybe 1) > transistors. Hehehe, I hate AAA's too. :) I'm thinking if I could adapt the Thomas circuit so that the PIC can turn it off. Thanks, Brusque ----------------------------------------------------------------- Edson Brusque C.I.Tronics Lighting Designers Ltda Research and Development Blumenau - SC - Brazil Say NO to HTML mail http://www.citronics.com.br ----------------------------------------------------------------- -- http://www.piclist.com hint: To leave the PICList spamBeGonepiclist-unsubscribe-requestspamBeGonemitvma.mit.edu

Let me see if I can remember how I did this... it's been a while, but I built a parallel printer tester back in about '92 or so, using an 8748. Power was derived from a 9V battery or *any* wall-wart up to about 24V AC or DC. I used a bridge rectifier, followed by a P-MOSFET with the gate tied high with a 100K resistor, as I recall. Of course a voltage regulator followed. Power ON was by plugging into a printer cable with a printer attached, which grounded the gate on the MOSFET -- of course this could just as easily have been a pushbutton, but my design was completely switchless. One could very easily use a PIC output pin, set it LOW on power up, tri-state it (make it an input) to shut down completely. In my printer tester, it just stayed turned on while plugged into a printer. Pretty nice, you could throw it into a tool box without having to worry about whether it was still on, or would get turned on by accident. Hope this helps, and hope I didn't mis-remember any of the details. Dale -- "Curiosity is the very basis of education and if you tell me that curiosity killed the cat, I say only the cat died nobly." - Arnold Edinborough On Mon, 5 Aug 2002, Roman Black wrote: {Quote hidden}> There is a design for self switched PIC here: > http://www.romanblack.com/self_swi.htm > > uses one cheap tiny (TO-92) SCR, and 2 resistors, > will work with a 7805 reg or just with the battery > and the PIC. :o) > -Roman > > > > > A.J. Tufgar wrote: > > > > Edson, > > Have the second pole of all your buttons goto an 2 input or gate. > > and the output of the or goto the pic power pin (you'll have to make > > sure it handle you pic's current load or you'll have to put some sort > > of driver behind it). The other input goes to a pic i/o pin. > > > > When a button is pressed it will turn your pic on via the or gate. > > Your pic then changes the line going to the or gate high, so if the > > user releases the button before your pic is done it keeps power to > > itself. When it's done set the line low and it will lose power. > > -- > http://www.piclist.com hint: To leave the PICList > TakeThisOuTpiclist-unsubscribe-requestEraseMEspam_OUTmitvma.mit.edu > > -- http://www.piclist.com hint: To leave the PICList RemoveMEpiclist-unsubscribe-requestTakeThisOuTmitvma.mit.edu

>?> When sleeping, the PIC16F628@4MHz consumes about 42uA @ 5V. If I suply >> it with some AA Alkaline batteries, it would mean rougly: >> 2850mAh / 42uA = 67857 hours = 2827 days = 7.74 years without use. > >I know that this was only a calculation to determine how heavy the load was >compared to the battery's capacity but do note that an Alkaline battery has >a shelf life of around 3 years (some manufacturers claim longer). If you >produce equipment with very low current drains then the reduction in battery >capacity with time can make serious inroads into the actual operating time. >When that happens, Lithium batteries are a possible solution. In this >particular case it's not an issue as your expected operating lifetime is >far shorter. but you probably should put some sort of disclaimer in your instruction manual recommending replacement of the batteries every 12 months (or whatever lesser period you feel you need) "to ensure reliable operation of the product". -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Many PICs run only with a 3V supply. I have one using a 16LC505 with a 4x4 key matrix on port B and an IR LED in series with a 10R resistor both driven by a transistor conected through a 1k resistor to one of the PIC pins. It wakes up on port B change, so when a key is pressed it sends an IR bit stream (it repeats four times the same code, just to make sure it will be correctly received) related to the code of the desired function and then it goes to sleep, and when the key is released, the PIC wakes up once again, sending a "stop everithing" code. It was not the best choice, sometimes the reception fails and I do not get the function or I do not get the "stop" condition, but most of the times it works. Edson Brusque (Listas) wrote: {Quote hidden}>Hello, > > We're wanting to make our own remote control for using with our >products. So, I'm doing some experiments with wake-on-rb-change, learning >remotes etc. > > One thing that is bothering me is how to make the power supply of a >remote control. An ideal supply would draw zero miliamps from the battery >when the PIC is sleeping. I could do the supply simply using a battery and a >78L05, but the regulator would draw some energy from the battery even >without the microcontroller. > > Any sugestion? Someone have the squematics of a remote control using a >PIC? > > Thank you very much, > > Brusque > >----------------------------------------------------------------- >Edson Brusque C.I.Tronics Lighting Designers Ltda >Research and Development Blumenau - SC - Brazil >Say NO to HTML mail http://www.citronics.com.br >----------------------------------------------------------------- > >-- >http://www.piclist.com#nomail Going offline? Don't AutoReply us! >email listservEraseME.....mitvma.mit.edu with SET PICList DIGEST in the body > > > > > > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Edson Brusque (Listas) wrote: > > Hello Roman, > > > There is a design for self switched PIC here: > > http://www.romanblack.com/self_swi.htm > > as always, your design is very smart, congratulations. Maybe I'll use > it. Thanks! > > The only think I don't like is that your web pages don't show very well > with Opera and I'll have to use IE (argh). :^) Wow!! I deliberately use only the two most basic html commands [img src=] for pictures and and [a href=] for navigation links, these are standards and should be supported by every browser under the sun. There are no frames, java, flash or ANYTHING that can cause problems. What problems did you get? :o( -Roman -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Hello Roman, > Wow!! I deliberately use only the two most basic > html commands [img src=] for pictures and and [a href=] > for navigation links, these are standards and should be > supported by every browser under the sun. There are no > frames, java, flash or ANYTHING that can cause problems. > What problems did you get? :o( It's probably is a problem with Opera. The section from "the circuit shown" and bellow show without any linefeeds. It seens you don't have any 0x0D/0x0A characters sequence, but I'm looking at the source code and the line-break characters are there. Strange... Best regards, Brusque ----------------------------------------------------------------- Edson Brusque C.I.Tronics Lighting Designers Ltda Research and Development Blumenau - SC - Brazil Say NO to HTML mail http://www.citronics.com.br ----------------------------------------------------------------- -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Edson Brusque (Listas) wrote: > > Hello, > > I'm making some measurements and I've found some interesting numbers. > > When sleeping, the PIC16F628@4MHz consumes about 42uA @ 5V. If I suply > it with some AA Alkaline batteries, it would mean rougly: > 2850mAh / 42uA = 67857 hours = 2827 days = 7.74 years without use. Not true! :o) The capacity as shown is generally for 10 or 20 hour discharge times. These are high enough currents that internal leakage current does not affect the capacity. Once you factor very slow discharge currents the internal leakage may be much more than your 42uA PIC. Probably about double, which would explain shelf lifes of 3 years etc. ;o) -Roman -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Try Mozilla 1.1b (quite stable now), as you don4t like M$IE ;-) Francisco Edson Brusque (Listas) wrote: {Quote hidden}>Hello Roman, > > > >>Wow!! I deliberately use only the two most basic >>html commands [img src=] for pictures and and [a href=] >>for navigation links, these are standards and should be >>supported by every browser under the sun. There are no >>frames, java, flash or ANYTHING that can cause problems. >>What problems did you get? :o( >> >> > > It's probably is a problem with Opera. The section from "the circuit >shown" and bellow show without any linefeeds. It seens you don't have any >0x0D/0x0A characters sequence, but I'm looking at the source code and the >line-break characters are there. > > Strange... > > Best regards, > > Brusque > >----------------------------------------------------------------- >Edson Brusque C.I.Tronics Lighting Designers Ltda >Research and Development Blumenau - SC - Brazil >Say NO to HTML mail http://www.citronics.com.br >----------------------------------------------------------------- > >-- >http://www.piclist.com hint: PICList Posts must start with ONE topic: >[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads > > > > > > -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics