Recent content by sniper887

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    PicAxe peak-detecting NiMh battery charger

    After having trouble making switchmode battery chargers, I decided to build one using an LM317 adjustable regulator and series resistor as a constant current source. Gets hot but works well. Schematic designed on Eagle. PCB produced with Oshpark. #terminal 4800 init: ;set up inputs and outputs...
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    Battery charger issue

    I'm getting strange behavior with this NiMH battery charger circuit where it will start charge even with no battery inserted. It worked fine for months but a couple days ago started with this problem. I haven't yet removed the circuit board from the charger to debug and see what the ADC is...
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    More Picaxe Battery Charger Issues

    Picture of a couple of them built.
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    More Picaxe Battery Charger Issues

    Here's the schematic:
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    More Picaxe Battery Charger Issues

    How's this for a buck converter setup? I'm not sure how to hook up the Picaxe inputs to the circuit. I have one for the current-sense resistor I moved to between the 5V supply and the battery being charged, and one for the negative terminal of the battery. I just put in series resistors to (in...
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    More Picaxe Battery Charger Issues

    Original thread with background on this problem: I've tried the suggestions and had a couple of the circuit boards work, and some not work. I've tried diodes on the output, both in series with the battery being...
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    Picaxe battery charger issues.

    What I saw on the O'scope.
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    Picaxe battery charger issues.

    I have attempted to build a battery charger for AA size NiMH batteries and have been running into an issue. With the current setup if I connect a battery the Picaxe repeatedly resets, unless I add a 10 or 15 ohm resistor in series, then it works properly. I'm thinking when the MOSFET turns on it...
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    WS2812 RGB LED with integrated driver.

    Would a Picaxe be able to control one of these? Its communication protocol doesn't seem to work like any others I've seen like i2c, SPI or serial.
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    Can an incorrect download circuit damage a PicAxe?

    I built a SMD circuit with a Picaxe 20M2 and the SMD programming jack sold with them on techsupplies. The programming circuit is correct, but the programming jack was installed 180 degrees out, meaning GND and serial out were reversed, and serial in was in the same place. I figured out the error...
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    Multiple use of Lookup

    Working on the code for my TLC59108 RGB LED project, I wanted to reference the same lookup table, but in different spots for different LED boards. The idea is having the colors run from one LED board to another. I've tried to have one part of the code gosub to the subroutine with the lookup...
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    I2C over twisted pair

    I have been working on a multiple RGB LED project, with an 08M2 I2C master, sending signals over 4 conductor cable to TLC59108 LED drivers on separate boards, daisy-chained together. The problem I'm having is on the LED board furthest from the master. It usually works but occasionally will stop...
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    Picaxe 18X I2C communications with PCA9622 I2C PWM LED driver, ROYGBIV color fade

    Took me a while to crack this, getting the I2C commands to work on the PCA9622. This circuit controls a single RGB LED and fades through the colors of the spectrum. Now to find something to light up with it. With the WRITEI2C commands the PCA9622 wouldn't work unless I took out the register...
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    External I2C ADC led driver

    This is a constant-current LED driver I made using the Picaxe 18X, ADS1115 external I2C analog to digital converter, and an IGBT to do the switching. Wanted to make it so it fits into a light socket with a socket to outlet adaptor. I've determined the LEDs need more heat sink area than they...