Recent content by nbw

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    Using a double-DAC MAX519, with I2C

    OK... latest update [it will make you laugh] I tried Hemi's code again, still got the flashing. The red LED flashing was kind of in time to the other two LEDs slowly PWMing up. Made me wonder what if. Using a current limiting resistor, I connected the red LED direct to 5V. It flashed. It's a...
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    Using a double-DAC MAX519, with I2C

    Hmm. When one, ahem, re-reads the datasheet... it does in fact 'suggest' on the 519 that pins 13 and 15 are references for the DAC 0 and 1 inputs. Tomorrow night I'll re-try the MAX519, seeing as the 3-PWM-from-14m2 could be a dead end. Third option.... maybe use an old 18X (with a PWM) as a...
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    Using a double-DAC MAX519, with I2C

    Just gave it a quick try - I had a few minutes - the C.0 port still does the weird flashing thing. I slowed it down to 4000Hz - it still flashes but I noticed something a bit different. The red LED (flashing one) has an off state. Then quickly increases a little bit in brightness over a...
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    Using a double-DAC MAX519, with I2C

    Thanks for that - I'll give it a go. I'm out on a date tonight so short of time - I hope she appreciates she's using valuable PICAXE testing time haha!
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    Using a double-DAC MAX519, with I2C

    I had those not connected; my understanding - maybe wrong? - was that they were used if you wanted to drive higher voltages outside of the DAC range? I'll re-check. I've disconnected the MAX519 for now while I attempt to get all 3 PWMs on the 14m2 going, but easy enough to re-breadboard
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    Using a double-DAC MAX519, with I2C

    Doing some research, multiple pwms has caused people issues in the past... I'm looking for some "simple" hpwm code to see if I can sneak a third pwm on my 14m2 that way.........
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    Using a double-DAC MAX519, with I2C

    Also tried it on C.0. Noticed something interesting. In the above code loop the red LED flashes slowly at the start of the loop, then noticeably speeds up towards the end.
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    Using a double-DAC MAX519, with I2C

    Hmm odd. I connected three LEDs with current limiting resistors to PWM outputs B.2, B.4, C.2 on my 14m2. The ones on B.2 and B.4 function fine. The one on C.2 flashes when I PWM it - even with the other two out of the code. I'll check in the Manual if there's a limit on how many I can use...
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    Using a double-DAC MAX519, with I2C

    Oh, well I've learned something new today. I thought there was only one PWM module, but connected to a variety of pins?!!? But, checking... yes, I'm out of date. Using 3 of the PWMs on the 14m2 would work well, I have enough pins I/O for the rest. Would be interested to know what I'm doing wrong...
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    Using a double-DAC MAX519, with I2C

    Hi everyone, I have a simple project that I haven't quite managed to get working - I did a search on similar Maxim chips (517,518) but can't get sample code working there either. It's a simple project, a large brass and copper art piece in the form of a goldfish. The electronic part is the eye...
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    FVR and battery voltage

    Right, got it working now! Larger resistor voltage divider, and wrapped my head around the FVR concept. I'm going to take a look at AllyCat's "divider-free" approach as it won't kill me to learn a second thing this week. Thanks all above :-) ^^^^
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    FVR and battery voltage

    OK, I went for Rtop of 27.7K, Rbott of 18.04K (1% resistors). Gives a very close ratio to Hippy's suggestion, with reduced current draw. So say 4.5V will be reduced to 1.755V at my ADC pin. That's fine. Is it then simply a matter of initiating the FVR to the 2.048V reference, quickly reading...
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    FVR and battery voltage

    I'm going to use hippy's suggested ratio, then double it as you suggest to lower current draw... thanks
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    FVR and battery voltage

    Thanks Hippy, I shall make a cup of coffee and digest your thoughts there - thanks! Straightaway I can amend the voltage divider as you suggest, and increase the resistors proportionally to reduce current drain. I'll let you know how I get on. I'm not sure still exactly how fvrsetup comes into...
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    FVR and battery voltage

    Hi everyone. It's been about 5 years since I've been on here. I need a bit of guidance with FVRSETUP etc. Here's the project: a simple clap switch (works fine) based on an 08m2. It's run off a 4.2V Li-ion battery, and I'd like to keep an eye on the battery voltage, so I can alert if the battery...
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