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  1. V

    Multiple download cable connection

    I’m looking into parallel processing using two PICAXE 28X1, with one as Master and the other as Slave. Both have serial download cable ports and it’s a pain switching from one port to the other to reprogram Master or Slave. I was thinking of doing something like this: Pins 14 and 15 are on an...
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    Running average

    I'm trying to add a running average on a PICAXE 28X1. I have two options: 1) Keep track of the average (A) and number of data points (N), or 2) Keep track of the number of data points and a running total (T). With either option, I can end up with an overflow error (i.e $FFFF goes to $0000)...
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    DS3232 and battery backup.

    I’ve added a DS3232 RTC (http://datasheets.maxim-ic.com/en/ds/DS3232.pdf) to my picaxe project , and everything’s working supper, except when removing power to the Vcc pin of the DS3232. When I put power back on this pin, the time goes back to midnight, January 1, 2001. I...
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    4MHz to 8MHz and pulsin

    If I change the Picaxe clock speed from 4MHz to 8Mhz and Pulsin is calibrated to 4MHz, should I devide calibrated pulsin results by 2? :confused:
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    PWM vs. ADC

    I’m using a PICAXE 28X1 and reading ADC current thru a load. I’m also using PWM to vary current thru the load (see att 1). The PIC reads current using a 0.05 ohm shunt going to an op-amp (gain 10). I think I’m getting some kind of interference between PWM and ADC reading. The PWM interface...
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    Measuring current

    I’m trying to measure current using the voltage drop across a resistor. It’s basically a battery charger. The simplified circuit is attached. “A” is common "–" between picaxe and battery. I need to measure the voltage drop across A and B, but B is more negative than A. Any idea how I can...
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    PWM shape

    Anyone know the approximate shape of a PWM signal from a 28X1? Say at 5KHz (pulse width of 0.2ms), what would be a typical rise and fall time?
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    Measuring low RPM

    I have a set up that sends a +5V pulse to a Picaxe 28X1 for every revolution of a wheel on an axel. I would like to measure Revolutions Per minute (RPM), in the 30 to 600 range (i.e. 0.5 Hz to 10 Hz). I was hoping to use Pulsin, but that has a maximum of 0.65535 secs. I figure this command...
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    PWM problem

    I’m a newbie with this stuff and I need help. I’m trying to use a Picaxe 28X1 to drive a PWM switch. I’m using a small 12VDC fan as test load. I made this circuit on a solderless board (attached 1). The Picaxe drives an opto (4N35), which drives an IFR540 from a regulated +5V supply...
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