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    20M2 32KHz external resonator

    The plan is to build a clock with a 20M2 I have laying around. I searched around a bit, but I keep coming back to this thread: http://www.picaxeforum.co.uk/showthread.php?7142-Very-Accurate-18X-Timing I'm a bit puzzled. How do I use this with the 20M2, and will I still be able to use the...
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    PICAXE USB serial download cable for 1.8v and 3.3v circuits.

    I want to read/write(but mainly read) from the serial console of my Raspi and Kindle, which run at 3.3v and 1.8v respectively. What is the simplest way to do this with the 5v USB serial cable that I have for my PICAXE? I think that for writing, I can use a voltage divider of 2 resistors. What...
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    I²C read flag?

    I have an application where I'm using pulsin and run the 20X2 in I²C slave mode as well. The idea is that the I²C master reads out the pulse length, but accuracy is bad when the read happens during the pulse. What I'd like to do is, only doing a pulsin after a read. So, say there is a read...
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    20X2 internal pullups for I2C

    I'm currently using the internal pullups on my I2C lines, but the guide just says they are "weak pullup resistors", are they suitable for this job? I can successfully communicate with the PICAXE(slave mode), but I notice that if I read values from it in a tight loop, I get bogus values. Could...
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    Measure resistance on an AC circuit

    Hm, sorry, I didn't exactly find what I was looking for. The thread you linked to seems to use a PWM signal, which goes between 0 and x, not between x and -x, which brings me to the other thing I found: If you just measure a short pulse occasionally, you wont degrade your probe that fast...
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    Measure resistance on an AC circuit

    I found out how to make my own moisture sensor, but it needs to run on AC, to avoid electrolysis. I also figured out I need a precision rectifier to be able to measure the resistance over the moisture sensor. The problem is that I'm a little confused how the ground works with respect to the AC...
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    Servo control circuit

    It's working! Thanks for your patience and support.
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    pulsin inaccuracy

    I'm positive the board is thoroughly cut under the PICAXE. Could you clarify the second check? In my interpretation, there is absolutely no connection between the programming header and B.2, so if what you say is true, it could very well be the problem.
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    pulsin inaccuracy

    No, this is what I'm testing: It doesn't even make it to 0.6V, more like 0.1V-0.3V. Could it be that… it's… broken? :( I tested B.3 as well, and that too gives 4.x volt.
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    pulsin inaccuracy

    I started soldering my servo board, piece by piece. What I have now is just the serial connection(works), the I2C connection and power(works) and finally a PWM input with 10K pulldown. Pulsin prints values ranging from 100 to 230 most of the time, which is about the expected range for a servo...
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    Servo control circuit

    I created a stripboard layout, so unless someone notices a big flaw in it, I'm going to solder it to the board tomorrow, and then pray it works. Thanks for all the feedback so far.
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    330 Ohm protective resistor

    Sorry. I was trying to understand the broader concept of applying resistors, but I apparently conflated several uses of a resistor. I tried to understand the servo and led case in the manual, to apply it to my case, where I need to protect the PICAXE from the higher voltage from the 5V source.
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    330 Ohm protective resistor

    I have read in several places that it is recommended to put a 330 Ohm resistor on, for example, a led or servo, attached to the PICAXE. I am trying to understand some basic electric principles here. I read a bit about Ohms law, and from what I understand, I need to know the resistance of the...
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    Servo control circuit

    Well, because, to be honest, I don't like the upload system(or it does not like me, I'm not sure) and JPEG is an inferior format for graphics. But if it makes you happy, I downloaded the PNG, converted it to JPG, uploaded it, and crossed my fingers. [edit] I also think I noted a flaw already...
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    Stripboard components with unsuitable leads

    How do you connect them? Just glue and wire, or is there something more sophisticated you can do? I want to solder an RJ11-style socket to a stripboard, but it has the pins in two small alternating rows.
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    How do I read the 4053 datasheet?

    I've been putting files in my Dropbox, because I can't get uploads to work. Now I at least managed to get an error message from the basic uploader, telling me my file can be 460x280px. That seems to work, but is not very useful. Anyway, I'm glad we're on the same page now. Any thoughts about...
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    How do I read the 4053 datasheet?

    For my servo control project, I need to switch between manual control(RC receiver) and autopilot(PICAXE), but it seems reading 4 PWM servo inputs into the PICAXE is not a good idea. So therefore I got a 4053, so that I can read one input into the PICAXE, and let it switch 3 outputs between...
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    Where to get a simple scope?

    It seems that to do anything serious with the PICAXE, one needs a oscilloscope. Maybe a nice addition to the starter pack? I looked around, and at first I found only bulky boxes of €200 and more, or very old and broken versions of the same concept for €50 or more, but then I found a USB one for...
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    Generating stripboard layouts

    Now that my servo controller project is making some progress, I started to think about how to lay out the schematic I have in mind on the stripboard I bought. It's not entirely trivial to make sure all the correct lanes are connected, and only those. That is why I started writing a piece of...
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    Servo control circuit

    Hi, I'm a programmer who's almost completely new to building my own circuits. The plan: Build a servo controller that can be controlled via I2C, with backup from a receiver. I found an existing circuit for the first part, and it doesn't seem to complicated to add a few servo inputs as well...
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