I have an RPi board setup with a picamera attached, I am wondering if this fun board could be used to act as a flash device for taking some pictures in a very dark or absolutely dark room? I think somebody mentioned that the LEDs were very bright, but how bright?
I have an RPi board setup with a picamera attached, I am wondering if this fun board could be used to act as a flash device for taking some pictures in a very dark or absolutely dark room? I think somebody mentioned that the LEDs were very bright, but how bright?
Ray
As far as I know, the Raspberry Pi can't control these LEDs directly. You need some sort of microcontroller between the RPi and the LEDs to provide the precise timing signals.
I think the brightness levels are listed in the datasheet. While these LEDs are bright, they aren't nearly as bright as a camera flash. I believe they also take longer to turn on than a flash.
When working with these LEDs, I generally keep the brightness turned down to about a third of their total brightness. The LEDs are uncomfortable to look at when they're close and set to their highest brightness level. While these LEDs are bright, I don't think they're particularly brighter than many other LEDs.
I just noticed Parallax is giving away one of their Fun Boards with each purchase.
I thought it was pretty cool to see my photo from post #63 (and #48) used in the banner. I think it's kind of ironic that the photo on the right (which I took) doesn't show the Parallax board but the board I designed. Not that I mind.
Our boards are pretty similar in design. It looks like the Parallax board is a bit taller to make more room for the silkscreened text. My design has curved sides so the the PCBs kind of interlock when set next to each other. I like the curved sides but I don't think this shape would be very easy to mass produce.
It looks like the distance between the edge of Parallax's board and the holes for the headers are spaced appropriately to allow linking the boards with jumpers.
If any of you have multiple Fun Boards and have added the headers, I'd be curious to see if you can link the Parallax boards together with jumpers.
You are either a heck of a nice guy (and you do seem to be) or have a great sense of humor. (or both) It just hit me that Parallax used your image with your boards for their ad.
That's cheating Parallax..
Edit: Reading your post closer, I see you mentioned that.. LOL.
You can blame me for the size of the board -- I did it as a project for my Nuts & Volts column. After the excitement of the IronMac shield at DefCon, Ken did a bit of analysis of web traffic and found that there was a lot of searching for WS2812s on the Parallax site. I already had this design in hand, so Daniel Harris spruced it up for production. God knows the Propeller is the best platform for controlling WS2812s; it just makes sense for Parallax to sell them.
As far as I know, the Raspberry Pi can't control these LEDs directly. You need some sort of microcontroller between the RPi and the LEDs to provide the precise timing signals.
I think the brightness levels are listed in the datasheet. While these LEDs are bright, they aren't nearly as bright as a camera flash. I believe they also take longer to turn on than a flash.
When working with these LEDs, I generally keep the brightness turned down to about a third of their total brightness. The LEDs are uncomfortable to look at when they're close and set to their highest brightness level. While these LEDs are bright, I don't think they're particularly brighter than many other LEDs.
Hello!
Correct. Neither the Raspberry Pi or the Netduino version 1 can do this. The Propeller version one certainly can. Oddly enough the Arduino can also. I've looked at the two I have here, (Would one of the brass PM me please so I can explain how that happened.) and they look considerably better then the set of breadboard friendly pixels from Adafruit I do have. Those are http://www.adafruit.com/products/1312 and look like this:
Oddly enough its a case of greater minds think alike. It seems someone at both shops or even yourself Duane, or you JonnyMac, came up with a good idea for the ones that Parallax sells. And independently and also earlier, our friends at Adafruit came up with those. (Which I've run on the Propeller.)
Now we do know that the Basic Stamp hasn't the capability to drive these directly. But what about indirectly? The Stamp would produce the data the user wants, and the Propeller would take it and translate it into a form that the pixel does understand? I can write the Stamp code very easily, it is the Prop code that I confess I can't.
I work with legenday Hollywood make-up/effects master, Steve Wang, and on projects he's built for Riot Games there was NO POSSIBLE WAY the Arduino would have worked. We're doing complex, multi-layered animations while refreshing the LED string at 300Hz. The Arduino can handle very simple WS2812 applications (within the constraint of memory, speed, and code complexity), but it doesn't come close to the Propeller in this regard.
I can write the Stamp code very easily, it is the Prop code that I confess I can't.
I would suggest that with just a little more practice, you could in fact write Propeller code as easily as your write BASIC Stamp code. For me, it's tricky writing Stamp code now (I do for my customers at EFX-TEK) because I'm always splitting apps into multiple processes; it has become my mindset.
Now we do know that the Basic Stamp hasn't the capability to drive these directly. But what about indirectly? The Stamp would produce the data the user wants, and the Propeller would take it and translate it into a form that the pixel does understand? I can write the Stamp code very easily, it is the Prop code that I confess I can't.
Apparently, this board can drive the WS2812B LEDs and it has the advantage of using 5V logic directly. You could probably use one of these between a BS2 and a chain of WS2812B Fun Boards.
I'm in the process of modifying the code previously used in the Eddie robot to work with the Activity Board. I thought a couple additions to the code would be fun. One possible fun addition would be to add WS2812 support. This would allow a Propeller board loaded with the code to control WS2812 LEDs with some simple serial commands.
A Basic Stamp could then send serial commands to the Propeller board and the Propeller board would take care of lighting the LEDs.
I like both Duane's and Parallax's design, for putting 5V in the center post. Seems like a more logical arrangement to avoid reverse polarity, but I'm guessing Adafruit did theirs (ground in the center) for a reason. Would be interesting to know if that's the case.
According to Adafruit's Neopixel page, an Arduino Uno can drive up to 500 LEDs at 30 fps. Mind you, that's probably with their library, which has a lot of ASM code in it. I can imagine for many SFX projects 30 fps is no where near fast enough, but for the typical user, it's probably adequate.
Is this issue with the Propeller because it has 3.3V logic? I know a logic shifter is easy to built, but given this comes up time and time again, I can't understand why Parallax doesn't create a simple multi channel shifter breakout board. Sparkfun's various shifter breakouts seem popular enough that they've continued making and selling them year after year.
According to Adafruit's Neopixel page, an Arduino Uno can drive up to 500 LEDs at 30 fps. Mind you, that's probably with their library, which has a lot of ASM code in it. I can imagine for many SFX projects 30 fps is no where near fast enough, but for the typical user, it's probably adequate.
To be fair, Jon's WS2812B code also has ASM in it. The driver itself is completely written in PASM. Nothing wrong with assembly language.
To be fair, Jon's WS2812B code also has ASM in it. The driver itself is completely written in PASM. Nothing wrong with assembly language.
That's not the issue. My driver runs in its own cog and consumes no time from the mainline code to update LEDs. In controllers like the Arduino that use interrupts to update the LEDs, there will ultimately be a practical limit to the time one can spend in the interrupt.
And, FWIW, the Propeller Assembly to run those LEDs is FAR easier to read and tweak that the teeth-gnashing code required in most Arduino models.
That's not the issue. My driver runs in its own cog and consumes no time from the mainline code to update LEDs. In controllers like the Arduino that use interrupts to update the LEDs, there will ultimately be a practical limit to the time one can spend in the interrupt.
And, FWIW, the Propeller Assembly to run those LEDs is FAR easier to read and tweak that the teeth-gnashing code required in most Arduino models.
No doubt that is all true. My point was just that both solutions involve assembly language.
If I were doing a task-intensive project with lots of inputs or outputs, I wouldn't use an Arduino, ASM or not, or even a Mega (maybe a Due, but I think that's cost overkill).
I did a MIDI project with an Arduino Uno and it was a very painful experience. Ran into all the interrupt and timer limitations inherent in the architecture. The project involved real-time pseudo-music generation, IR control, multiple non-blocking timer delays, interrupts, and several other features. The same project done with a Propeller took two evenings, as opposed to the 10 or 11 for the Arduino.
No question the LED module is the type of project ideal for the Propeller, which could control the lights, play music, read buttons and other sensors for input, and display some video all at the same time.
Here is another WS281x driver. I originally did it for Pololu.com LEDs; it drives parallax chips just fine. It is intended for strings of LEDs; you can configure the number of strings and the number of LEDs per string. It has a nice kind of moving effect. I am not posting a video because, try as I might, I cannot get a digital camera to work with it.
The light-emitting portion of the pololu devices are physically MUCH larger than the Parallax; you pays yer money and you takes yer choices. At the very top of the program are two commented CONs; you have to uncomment one or the other.
I generated timing by counting instructions; that is different from JonnyMac who used waitcnt's.
You guys were having way too much fun in this thread, so I added some WS2812's to my Adafruit order last week.
I ended up getting one string of 60, and some multi-pixel modules. They did not stock Parallax's nice single LED module (or Duanne's) but did have sticks of 8, and some cool rings!
I see you have this pretty much under control. I have just started to use the ws2812, I got the color down, but now I want change the brightness of the led. I am using the ws2812.h I was wondering if it can be done through it?
I see you have this pretty much under control. I have just started to use the ws2812, I got the color down, but now I want change the brightness of the led. I am using the ws2812.h I was wondering if it can be done through it?
Just use the COLORX macro in ws2812.h. The fourth parameter is the brightness.
Is Parallax still throwing in a free one with each order? I placed an order tonight that included a ten pack and want to make sure if there is a free one I do not toss it like some people have almost done!!!
Is Parallax still throwing in a free one with each order? I placed an order tonight that included a ten pack and want to make sure if there is a free one I do not toss it like some people have almost done!!!
According to the "Parallaxian" they sent out (with a picture of my design), the offer ended December 23.
Did any fellow Parallaxians receive a free LED module after this date?
The second photo is my Activity Board with some WS2812B boards I made a while ago.
With headers added to the individual boards, the boards can be linked together into rows using jumpers. .
Maybe Parallax should include an easy way (and reasonably priced way) to purchase extra jumpers to use with these boards?
Hello!
I'll have photos of a PAB wearing these devices soon, but I can confirm that the two of them do work with the original code from yourself Jon, set to four by the way. Picture this in the first and second photos that Duane took, instead of four of the new ones from Parallax there are two of the bread board friendlies from Limor and company, and two of the new ones from Parallax
At first glance they look the same running as if the whole was all made by Parallax (which is next) but that's the beauty of the WS2812B devices. Depending on what does work,for example I might rearrange things so that the two from Parallax are arranged like the third photo with the two Parallax ones on the bottom swapped for the friendlies from Limor and the Parallax ones stuck on top like that.
I started my Computer Business way back in 1998. Since then I have fortunately amassed a nice collection of jumpers. I never knew what I would use all of them for but I now have something to use them on. I think a more permanent solution might be to use dual row headers.
If any of you have multiple Fun Boards and have added the headers, I'd be curious to see if you can link the Parallax boards together with jumpers.
BTW, The Parallax boards do link together with jumpers. Not as nicely as my design though. I designed my boards with the intention of linking them together with jumpers. Parallax's boards a just a smidge too wide to link together in a flat straight line. The Parallax boards still link together just fine, they just have a bit of a bend to them when linked with jumpers.
I used ten of Parallax's boards to display the encoder error in the video embedded in this post. The linked together boards can be seen in the video.
I think the person who included the photo of my boards thought the boards in the photo were the ones made by Parallax. I did send Parallax an email offering to replicate the photo with Parallax boards but I didn't hear back from them. I have a feeling my email fell through the cracks during the holiday rush.
I started my Computer Business way back in 1998. Since then I have fortunately amassed a nice collection of jumpers. I never knew what I would use all of them for but I now have something to use them on. I think a more permanent solution might be to use dual row headers.
As I mentioned in post #63, ElectroDragon sells 100 jumpers for $1.10. Jumpers are also useful for linking together LED arrays. Now that I have a bunch of jumpers on hand, I'm surprised how often I find a use for them.
These things are definitely cool to play with. Just curious, is there a way to make them work without a Propeller or an Arduino that is inexpensive, easy and a small footprint? I have something I want to do with some one offs and do not want to waste a Propeller on just one LED.
is there a way to make them work without a Propeller or an Arduino that is inexpensive, easy and a small footprint?
Not really. You need some sort of microcontroller to send the appropriate signals to the LED.
There are lots of different small inexpensive microcontroller boards for sale. Adafruit sells their Trinket and you can get clones of Arduino Pro Mini or Nano boards from a lot of different places for a few dollars.
It's possible to separate the WS2812B from a microcontoller after the control signals have been sent and the last color instruction will stay in effect as long as the LED has power. So you could use the Fun Board without a microcontroller as long as it stays powered. You wouldn't be able to change the color without reconnecting it to the microcontroller.
Comments
Ray
Here's the same photo I shared earlier showing how the jumpers are used to join the boards.
ElectroDragon sells 100 jumpers for $1.10. I've been surprised how often I use jumpers now I have lots of them.
The PCBs above are my own design but I'd be very surprised if the jumpers didn't also work with Parallax's board.
As far as I know, the Raspberry Pi can't control these LEDs directly. You need some sort of microcontroller between the RPi and the LEDs to provide the precise timing signals.
I think the brightness levels are listed in the datasheet. While these LEDs are bright, they aren't nearly as bright as a camera flash. I believe they also take longer to turn on than a flash.
When working with these LEDs, I generally keep the brightness turned down to about a third of their total brightness. The LEDs are uncomfortable to look at when they're close and set to their highest brightness level. While these LEDs are bright, I don't think they're particularly brighter than many other LEDs.
I thought it was pretty cool to see my photo from post #63 (and #48) used in the banner. I think it's kind of ironic that the photo on the right (which I took) doesn't show the Parallax board but the board I designed. Not that I mind.
Our boards are pretty similar in design. It looks like the Parallax board is a bit taller to make more room for the silkscreened text. My design has curved sides so the the PCBs kind of interlock when set next to each other. I like the curved sides but I don't think this shape would be very easy to mass produce.
It looks like the distance between the edge of Parallax's board and the holes for the headers are spaced appropriately to allow linking the boards with jumpers.
If any of you have multiple Fun Boards and have added the headers, I'd be curious to see if you can link the Parallax boards together with jumpers.
You are either a heck of a nice guy (and you do seem to be) or have a great sense of humor. (or both) It just hit me that Parallax used your image with your boards for their ad.
That's cheating Parallax..
Edit: Reading your post closer, I see you mentioned that..
Hello!
Correct. Neither the Raspberry Pi or the Netduino version 1 can do this. The Propeller version one certainly can. Oddly enough the Arduino can also. I've looked at the two I have here, (Would one of the brass PM me please so I can explain how that happened.) and they look considerably better then the set of breadboard friendly pixels from Adafruit I do have. Those are http://www.adafruit.com/products/1312 and look like this:
Oddly enough its a case of greater minds think alike. It seems someone at both shops or even yourself Duane, or you JonnyMac, came up with a good idea for the ones that Parallax sells. And independently and also earlier, our friends at Adafruit came up with those. (Which I've run on the Propeller.)
Now we do know that the Basic Stamp hasn't the capability to drive these directly. But what about indirectly? The Stamp would produce the data the user wants, and the Propeller would take it and translate it into a form that the pixel does understand? I can write the Stamp code very easily, it is the Prop code that I confess I can't.
Within limits of memory and what you want to do.
I work with legenday Hollywood make-up/effects master, Steve Wang, and on projects he's built for Riot Games there was NO POSSIBLE WAY the Arduino would have worked. We're doing complex, multi-layered animations while refreshing the LED string at 300Hz. The Arduino can handle very simple WS2812 applications (within the constraint of memory, speed, and code complexity), but it doesn't come close to the Propeller in this regard.
I would suggest that with just a little more practice, you could in fact write Propeller code as easily as your write BASIC Stamp code. For me, it's tricky writing Stamp code now (I do for my customers at EFX-TEK) because I'm always splitting apps into multiple processes; it has become my mindset.
https://www.adafruit.com/products/1501
A Basic Stamp could then send serial commands to the Propeller board and the Propeller board would take care of lighting the LEDs.
According to Adafruit's Neopixel page, an Arduino Uno can drive up to 500 LEDs at 30 fps. Mind you, that's probably with their library, which has a lot of ASM code in it. I can imagine for many SFX projects 30 fps is no where near fast enough, but for the typical user, it's probably adequate.
Is this issue with the Propeller because it has 3.3V logic? I know a logic shifter is easy to built, but given this comes up time and time again, I can't understand why Parallax doesn't create a simple multi channel shifter breakout board. Sparkfun's various shifter breakouts seem popular enough that they've continued making and selling them year after year.
That's not the issue. My driver runs in its own cog and consumes no time from the mainline code to update LEDs. In controllers like the Arduino that use interrupts to update the LEDs, there will ultimately be a practical limit to the time one can spend in the interrupt.
And, FWIW, the Propeller Assembly to run those LEDs is FAR easier to read and tweak that the teeth-gnashing code required in most Arduino models.
I did a MIDI project with an Arduino Uno and it was a very painful experience. Ran into all the interrupt and timer limitations inherent in the architecture. The project involved real-time pseudo-music generation, IR control, multiple non-blocking timer delays, interrupts, and several other features. The same project done with a Propeller took two evenings, as opposed to the 10 or 11 for the Arduino.
No question the LED module is the type of project ideal for the Propeller, which could control the lights, play music, read buttons and other sensors for input, and display some video all at the same time.
The light-emitting portion of the pololu devices are physically MUCH larger than the Parallax; you pays yer money and you takes yer choices. At the very top of the program are two commented CONs; you have to uncomment one or the other.
I generated timing by counting instructions; that is different from JonnyMac who used waitcnt's.
I ended up getting one string of 60, and some multi-pixel modules. They did not stock Parallax's nice single LED module (or Duanne's) but did have sticks of 8, and some cool rings!
First use of new PPDB. At least I know P16 works!
(Using Jon's demo)
According to the "Parallaxian" they sent out (with a picture of my design), the offer ended December 23.
Did any fellow Parallaxians receive a free LED module after this date?
No free modules have been included with any order shipped after this date.
Hello!
I'll have photos of a PAB wearing these devices soon, but I can confirm that the two of them do work with the original code from yourself Jon, set to four by the way. Picture this in the first and second photos that Duane took, instead of four of the new ones from Parallax there are two of the bread board friendlies from Limor and company, and two of the new ones from Parallax
At first glance they look the same running as if the whole was all made by Parallax (which is next) but that's the beauty of the WS2812B devices. Depending on what does work,for example I might rearrange things so that the two from Parallax are arranged like the third photo with the two Parallax ones on the bottom swapped for the friendlies from Limor and the Parallax ones stuck on top like that.
BTW, The Parallax boards do link together with jumpers. Not as nicely as my design though. I designed my boards with the intention of linking them together with jumpers. Parallax's boards a just a smidge too wide to link together in a flat straight line. The Parallax boards still link together just fine, they just have a bit of a bend to them when linked with jumpers.
I used ten of Parallax's boards to display the encoder error in the video embedded in this post. The linked together boards can be seen in the video.
I think the person who included the photo of my boards thought the boards in the photo were the ones made by Parallax. I did send Parallax an email offering to replicate the photo with Parallax boards but I didn't hear back from them. I have a feeling my email fell through the cracks during the holiday rush.
As I mentioned in post #63, ElectroDragon sells 100 jumpers for $1.10. Jumpers are also useful for linking together LED arrays. Now that I have a bunch of jumpers on hand, I'm surprised how often I find a use for them.
Not really. You need some sort of microcontroller to send the appropriate signals to the LED.
There are lots of different small inexpensive microcontroller boards for sale. Adafruit sells their Trinket and you can get clones of Arduino Pro Mini or Nano boards from a lot of different places for a few dollars.
It's possible to separate the WS2812B from a microcontoller after the control signals have been sent and the last color instruction will stay in effect as long as the LED has power. So you could use the Fun Board without a microcontroller as long as it stays powered. You wouldn't be able to change the color without reconnecting it to the microcontroller.