one led, then 2, then 3, then 4......

[charlie_r]

Ok, i get the point. it would be much simpler to use the PIC. Now, with VERY limited knowledge of those, and not wanting to have to lay out $$$$$$$$$$$$ for a programmer and learn how to use it for a one off project, who among you is willing to program a pair of PICs for me to accomplish this task?

 

[Sceadwian]

Charlie you obviously haven't looked up much about pics. You can build a programmer for 90% of all PICs using the parallel port on your PC and a few resistors transistors and caps. There are many progarmmer circuits available out there, many can be built on a breadboard. Do yourself the favor and learn about pic's (or AVR's my personal micro controller of choice =>)

 

[charlie_r]

much of what i've come up with, apart from these forums that is, everyone talks about buying a ready made programmer usually costing $40 to $80.

could it be that i haven't seen the right places? yes, that is a distinct probability!

am currently thinking about the PICAXE thing, it might do what i am looking for.

HOWEVER, going whole hog into this, i can see a scrolling sign on the back of my bicycle trailer with the message "watch for sudden stops and turns"

now THAT would take a few LEDs! hmmmmm how do those commercial units work??? PWM on a matrix??

you all have probably figured out by now that i am very weak on electronic theory etc. the last time i was doing anything in design was in high school, too many years ago to know what's available currently. i'll put it this way- most of the FM radio broadcast stations didn't know what stereo multiplexing was, let alone used it!


you young bucks MIGHT just be a bad influence on an old man!!

 

[Souper man]

You could use a extremely low frequency on a astable 555, connect the output to a 4017's clock input, and then you could connect as many LED's up (10 max) as you want, then connect the last LED output to the reset, and that will reset the count. Then it will start over again and again. Hope that helped.

 

[Roff]

You could use a extremely low frequency on a astable 555, connect the output to a 4017's clock input, and then you could connect as many LED's up (10 max) as you want, then connect the last LED output to the reset, and that will reset the count. Then it will start over again and again. Hope that helped.

I think you need to read the entire post. Or, if you did, you don't understand 4017s.

 

[charlie_r]

to heck with it! i've spent most of today looking into "build your own" type pic programmers........

MOST of what i've seen on a google search (term "build a pic programmer") has been seriously linked to "buy our kit" or "buy our sofware" meaning the d***ed things would likely not work without their crud. I'll say it again I DON'T HAVE $$$$ TO THROW AROUND!!!! (disabled with VERY low income!)

I do thank you all for your input, but I'm just going to have to kill this part of the project.

frustrating, to put it mildly.

 

[Souper man]

I think you need to read the entire post. Or, if you did, you don't understand 4017s.

I did! I have built the described circuit many times! Maybe there are other functions of the 4017 that i dont understand, but I do know the output tied to reset! This has been easily replicated!

 

[charlie_r]

that will advance each INDIVIDUAL led, shutting off the previous one.

as in:

10000000
01000000
00100000
00010000
00001000
00000100
00000010
00000001
10000000
01000000
00100000 and so forth.

what we were wanting is for the leds to come on one at a time until ALL are on then reset.

as in:

10000000
11000000
11100000
11110000
11111000
11111100
11111110
11111111
00000000
10000000
11000000 and so forth

 

[Nigel Goodwin]

MOST of what i've seen on a google search (term "build a pic programmer") has been seriously linked to "buy our kit" or "buy our sofware" meaning the d***ed things would likely not work without their crud. I'll say it again I DON'T HAVE $$$$ TO THROW AROUND!!!! (disabled with VERY low income!)

Perhaps you should try reading the 'sticky' at the top of the micro-controller?, which lists a great many programmers, with free software and free circuits!.

I also fail to see the relevence of your disability?, whatever it is, it makes no difference to your question, or any answers you receive.

 

[charlie_r]

Nigel,

I have read the sticky several times. I have followed several of the links, and had trouble understanding some of what was discussed. I don't have a very strong electronics background.

the only point about my disability is that i don't have but a few $ a month to use for my recreation. otherwise, i have no problem with doing electronics projects, what i can understand of them, that is.

Yes, I have looked at your website as well. The only problem I have with it is that right away you want people have all this equipment before discussing the theory and why & wherefore behind what they are doing.

 

[audioguru]

I have built the described circuit many times!

You built a different circuit.
This circuit needs one LED to light then it stays on when the second LED lights. Then they stay on when the 3rd LED lights etc.
A CD4017 lights only one LED at a time.

 

[Souper man]

Lol your right! You could connect the outputs with diodes though, that would give the desired effect.

 

[charlie_r]

Ok, I aplogize to any that were offended by the rant of earlier today.

I am venturing into - for me, at least - uncharted waters.

It is extremely hard for me, as I have very little electronics background.

I appreciate all the suggestions that you people have made.

I haven't totally given up on attempting to learn about PICs, just had a short bout of extreme frustration. After looking over souper's LVP threads, I have realized that I have a bit of a steep learning curve for a short while.

So, as a result, I will complete phase one of my lighting project, then add to it later with improved versions. Yes, I will post pictures as I complete each phase. In fact, I have part of it working already, on breadboard. Will fire it up tomorrow and take a few pics and post a link or three.


Oh, Souper? check out the comments about my idea on that.......top of page 2 this thread.

 

[charlie_r]

here is a still of the first phase of the project **broken link removed**

this is operating off of 7.2V (nominal) from a set of NiCDs i robbed from a couple of dead
drill packs.

i used 2 LM555N timers, a mod of the bowden bicycle flasher ckt. my mod:**broken link removed**

ic2 gives a high flash rate, and ic1 sends that signal to both sides alternately. the RC sections of them give
3 flashes then switches to the other set.

**broken link removed**of the set in action. kinda hard to see the fast flashing when each section is active, sorry about that. looks kinda like what is on most of the emergency vehicles around here.

i have used 1/8" plexiglass for the units, but will be using PCB for the rest of the projects. the LED units will have the correct colored lenses over each section, made from cheap driveway reflectors to aid in off-axis viewing. this doesn't seem to be reducing the light output by any appreciable amount.


however, since i will be needing to go to a PIC for the next phase of the project, i am thinking of abandoning the 555 thing in favor of PWM from a PIC. could lower the total draw of these things. if my meter is correct, i have a draw of 700+ mA with fully charged battery.

 

[audioguru]

It looks like your LEDs are on all the time (but the sides alternate), that is why the battery current is so high. If you flash them on for at least 30ms so they can be seen as being very bright, then a pause without light then the average current will be much lower.

PWM is used as a light dimmer. Low duty cycle equals low average current which equals low brightness. There is no free lunch with brightness.

 

[charlie_r]

ok, thanks.

i don't have access to a high enough speed camera to show the action very well, so you're going to have to take my word for it that they are flashing at a fairly high speed. the math works out like this:

for the high speed section, R1= 4.7K, R2= 51K, C1= 2.2uf. gives a calculated T1= 84.9mS, T2= 77.7mS, F= .0061 KHz

for the low speed (switching) side, R1= 4.7K, R2= 300K, C1= 1uf. gives a calculated T1= 211mS, T2= 207mS, F= .0023 KHz, or close to 1/3 of the high speed side, giving 3 flash then switch, 3 flash then switch.

 

[audioguru]

The LEDs are turned off for nearly half the time and the average current is 700mA. Then the LED current is nearly 1.4A.
You must have 70 ordinary 20mA LEDs on each side. I can't see in your fuzzy video.

 

[charlie_r]

each set is made up of 10, set in series/parallel. 2 LED w R, calculated current of 18.5 mA.

What i didn't have hooked up on the demo was the 2 boards for the front of the bike, which will give it a total of 80 LEDs, 40 at a time lit.

since my meter is a wally world semi-cheap unit, i have my doubts as to it's accuracy, although the math does seem to work out to 740mA.

the LEDs are from mouser, stock #604WP7113SEC/H for the red, and #828OVLGY0C9B9 for the yellow. both have 2.0-2.2Vf, and 20mA typical If.

I am planning on getting some sort of generator rigged up to power this so i don't have to keep cycling the NiCDs constantly.

 

[Omar.M]

Charlie,
I just would like to tell you about my "PIC Journey" which I started not too long ago, and I was in the same boat as you.
Being young, I could not afford the expensive programmers and so I searched and searched. I've learned that, as others have said, you can get really affordable programmers and chips-- there is probably a good enough solution out there for you.

Let me suggest to you this programmer:
"PIC-PG2C" (**broken link removed**)
You can find this around E-Bay and other hobby sites for about 15 dollars.

Most of these programmers use the same, free software (any of these will do):
http://freenet-homepage.de/dl4yhf/winpicpr.html
(Nigel wrote this. Gives you the option of bugging him-- but you didn't hear that from me =P)
http://www.ic-prog.com/

And on top of that-- you can rely on building your own programmer if you wish with a handful of components (and for schematics, just hit up Google). Just to give you an idea, this is how ghetto they get:
**broken link removed**

So Charlie, let this be a lesson to you. There are usually always options available-- just keep your doors open.
Also, I am pro-PIC because that is how I started and haven't had the time to switch onto AVRs (at least try them out enough to recommend them to others). But like Jake (Sceadwian) suggested, you can always try AVRs. To make the programmers, you really only need a few components and can throw one together in no time.
Hope things work out for you too,
-Omar

 

[logto]

i think a cheap MCU like pic12c508 or 89c2051 than add a 74hc595 is the best mothd