Comments for Hypomnemata http://blog.appliedplatonics.com Applied Platonics' Lab Notebook Thu, 22 Dec 2011 19:43:26 +0000 hourly 1 http://wordpress.org/?v=3.3.1 Comment on TI Launchpad: no Arduino killer by calin http://blog.appliedplatonics.com/2010/06/26/ti-launchpad-no-arduino-killer/#comment-305 calin Thu, 22 Dec 2011 19:43:26 +0000 http://blog.appliedplatonics.com/?p=191#comment-305 Just a heads up to anyone using this, you get a 5 volt output directly next to the usb thingy, its marked as tp1. Just a heads up to anyone using this, you get a 5 volt output directly next to the usb thingy, its marked as tp1.

]]> Comment on TI Launchpad: no Arduino killer by paul http://blog.appliedplatonics.com/2010/06/26/ti-launchpad-no-arduino-killer/#comment-292 paul Wed, 12 Oct 2011 08:39:05 +0000 http://blog.appliedplatonics.com/?p=191#comment-292 Hey Josh, LTNS :) This TI board looks more interesting than the $4.30 launchpad. It costs $29 but has lots better stuff: https://estore.ti.com/MSP-EXP430FR5739-MSP-EXP430FR5739-Experimenter-Board-P2430C42.aspx - cpu has 16k of ferromagnetic (nonvolatile) ram plus 1k of regular sram, plus some UARTs, timers, etc and it has a 32x32 hardware multiplier so it can do public key crypto or moderate DSP - board has 3d accelerometer, temperature sensor, 8 leds, 2 switches, and place to put a light sensor It is at least comparable to the fancier arduino boards in cpu power, and the FRAM is a unique feature. I wish TI would get its act together with these boards in some other respects of course. Hey Josh, LTNS :)

This TI board looks more interesting than the $4.30 launchpad. It costs $29 but has lots better stuff:

https://estore.ti.com/MSP-EXP430FR5739-MSP-EXP430FR5739-Experimenter-Board-P2430C42.aspx

- cpu has 16k of ferromagnetic (nonvolatile) ram plus 1k of regular sram, plus some UARTs, timers, etc and it has a 32×32 hardware multiplier so it can do public key crypto or moderate DSP

- board has 3d accelerometer, temperature sensor, 8 leds, 2 switches, and place to put a light sensor

It is at least comparable to the fancier arduino boards in cpu power, and the FRAM is a unique feature. I wish TI would get its act together with these boards in some other respects of course.

]]> Comment on Hack of the day: LED HSV wheel by jbm http://blog.appliedplatonics.com/2009/05/14/hack-of-the-day-led-hsv-wheel/#comment-252 jbm Fri, 13 May 2011 06:35:18 +0000 http://blog.appliedplatonics.com/?p=9#comment-252 No, actually, 8 still isn't PWM on the newer boards. I'll have to change the code back, oi. Apparently I was more clever a few years ago. Thanks for actually testing this, which I clearly didn't actually do (I've lost track of my Radio Shack LED, have a bunch of Chinese ones now...). The voltages there aren't maximums, but are just how much voltage it takes to light the LED. You definitely don't want to run the LED like this forever, but it shouldn't be a problem for a quick demo. To do this more correctly, you need resistors on each color's input, to limit their currents. These resistors are dropping the rest of the voltage, which determines the current flowing through the color, which determines the brightness. I can find (or write) a better explanation if you're really interested. No, actually, 8 still isn’t PWM on the newer boards. I’ll have to change the code back, oi. Apparently I was more clever a few years ago. Thanks for actually testing this, which I clearly didn’t actually do (I’ve lost track of my Radio Shack LED, have a bunch of Chinese ones now…).

The voltages there aren’t maximums, but are just how much voltage it takes to light the LED. You definitely don’t want to run the LED like this forever, but it shouldn’t be a problem for a quick demo. To do this more correctly, you need resistors on each color’s input, to limit their currents. These resistors are dropping the rest of the voltage, which determines the current flowing through the color, which determines the brightness. I can find (or write) a better explanation if you’re really interested.

]]> Comment on Hack of the day: LED HSV wheel by Cody http://blog.appliedplatonics.com/2009/05/14/hack-of-the-day-led-hsv-wheel/#comment-251 Cody Fri, 13 May 2011 05:35:10 +0000 http://blog.appliedplatonics.com/?p=9#comment-251 Hey, thanks very much for this code. I bought one of these LEDs today and you saved me the trouble of figuring out the code on my own (though it seems kind of fun, but messy). But I thought I should mention, the modified code didn't seem to work, I'm guessing that only pins 9, 10 & 11 are PWM, since that's what the label on the board says. (So that was a good reason to bend the anode around into 8.) (Upon further investigation I see this is specific to my older ATmega8 board.) Also, I'm kind of worried about LEDs burning out--the package said 2.6V max on the red, 4V max for the blue and green, and it looks like PWM full on is 5V? Hey, thanks very much for this code. I bought one of these LEDs today and you saved me the trouble of figuring out the code on my own (though it seems kind of fun, but messy).

But I thought I should mention, the modified code didn’t seem to work, I’m guessing that only pins 9, 10 & 11 are PWM, since that’s what the label on the board says. (So that was a good reason to bend the anode around into 8.)

(Upon further investigation I see this is specific to my older ATmega8 board.)

Also, I’m kind of worried about LEDs burning out–the package said 2.6V max on the red, 4V max for the blue and green, and it looks like PWM full on is 5V?

]]> Comment on Hack of the day: LED HSV wheel by jbm http://blog.appliedplatonics.com/2009/05/14/hack-of-the-day-led-hsv-wheel/#comment-249 jbm Fri, 25 Mar 2011 21:07:06 +0000 http://blog.appliedplatonics.com/?p=9#comment-249 <strong>EDIT: Don't listen to me. I was cleverer than I remember. Pin 8 doesn't support PWM on the Arduino, so it has to be the anode.</strong> The common anode is the longest pin, one of the ones in the middle. The code assumes you've bent it such that it goes into the next slot over (Totally obvious, right? Sigh. Sorry about that.)<del datetime="2011-05-13T06:36:24+00:00"> Try replacing the lines at the top of the file with this version:</del> <!-- // Don't swap red and anode, no matter how aesthetically pleasing it makes the code. // It confuses people because they have to move pins around, and it's not well-documented. // Sorry about that. int red_pin = 8; int common_anode = 9; int blue_pin = 10; int green_pin = 11; --> // That should fix it. EDIT: Don’t listen to me. I was cleverer than I remember. Pin 8 doesn’t support PWM on the Arduino, so it has to be the anode.

The common anode is the longest pin, one of the ones in the middle. The code assumes you’ve bent it such that it goes into the next slot over (Totally obvious, right? Sigh. Sorry about that.) Try replacing the lines at the top of the file with this version:

// That should fix it.

]]> Comment on Hack of the day: LED HSV wheel by Robert Merritt http://blog.appliedplatonics.com/2009/05/14/hack-of-the-day-led-hsv-wheel/#comment-248 Robert Merritt Thu, 24 Mar 2011 06:07:53 +0000 http://blog.appliedplatonics.com/?p=9#comment-248 I'm lost at the same spot but can't figure out what you did. what am I doing wrong. And btw/ big thanks for the code! I’m lost at the same spot but can’t figure out what you did. what am I doing wrong. And btw/ big thanks for the code!

]]> Comment on Greenwire (PCB fix-up) Workshop by Volksduinos in the Wild: Lasers pew-pe | Hypomnemata http://blog.appliedplatonics.com/2010/06/24/greenwire-pcb-fix-up-workshop/#comment-246 Volksduinos in the Wild: Lasers pew-pe | Hypomnemata Wed, 16 Mar 2011 06:16:46 +0000 http://blog.appliedplatonics.com/?p=183#comment-246 [...] First up: the laser drive circuit, as a teaser.  This is a part of a Noisebridge project that’s still a bit nascent, but it’s handy to know how to drive a higher current device from the Volksduino board.  Miloh is hooking up his Volksduino to a laser diode, adding some repurposed hard drive platters, and building a raster scanning laser display.  Note that this is a Volksduino v1.0, which was used in the Greenwire (PCB Repair) workshop. [...] [...] First up: the laser drive circuit, as a teaser.  This is a part of a Noisebridge project that’s still a bit nascent, but it’s handy to know how to drive a higher current device from the Volksduino board.  Miloh is hooking up his Volksduino to a laser diode, adding some repurposed hard drive platters, and building a raster scanning laser display.  Note that this is a Volksduino v1.0, which was used in the Greenwire (PCB Repair) workshop. [...]

]]> Comment on TI Launchpad: no Arduino killer by jbm http://blog.appliedplatonics.com/2010/06/26/ti-launchpad-no-arduino-killer/#comment-245 jbm Mon, 14 Mar 2011 03:50:06 +0000 http://blog.appliedplatonics.com/?p=191#comment-245 One thing TI got totally correct on Launchpad: the pin spacing is all 0.1"/2.54mm. Anyone can go to Radio Shack and pick up a standard prototyping board, and it will fit. If only they sold strips of header pins there, it'd be perfect. One thing TI got totally correct on Launchpad: the pin spacing is all 0.1″/2.54mm. Anyone can go to Radio Shack and pick up a standard prototyping board, and it will fit. If only they sold strips of header pins there, it’d be perfect.

]]> Comment on TI Launchpad: no Arduino killer by Clavis http://blog.appliedplatonics.com/2010/06/26/ti-launchpad-no-arduino-killer/#comment-244 Clavis Mon, 14 Mar 2011 03:38:49 +0000 http://blog.appliedplatonics.com/?p=191#comment-244 Another idea about the TI Lanchpad going , if they can just provide a simple i/o board with low value. hobbyist developer maybe could more focus on the how to extend the sensor and link the MCU on the small project (eg: build the proto-shield on it), and do not worry about the make MCU / USB-COM circuit by they own. Another idea about the TI Lanchpad going , if they can just provide a simple i/o board with low value. hobbyist developer maybe could more focus on the how to extend the sensor and link the MCU on the small project (eg: build the proto-shield on it), and do not worry about the make MCU / USB-COM circuit by they own.

]]> Comment on Hack of the day: LED HSV wheel by Matt http://blog.appliedplatonics.com/2009/05/14/hack-of-the-day-led-hsv-wheel/#comment-241 Matt Mon, 31 Jan 2011 03:41:25 +0000 http://blog.appliedplatonics.com/?p=9#comment-241 Oops I figured it out. Got the spec sheet on RadioShack.com and figured out how this all works. In any event, I should have mentioned first off that I really appreciate this code! Off to map values from TouchOSC to this :-) Oops I figured it out. Got the spec sheet on RadioShack.com and figured out how this all works. In any event, I should have mentioned first off that I really appreciate this code! Off to map values from TouchOSC to this :-)

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