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    FVR 1.024 positive reference question

    Hi all, The online manual for the FVR command says "Note that the 1.024V reference may not be accurate if used as the Vref+ of the ADC (only 2.048 or 4.096 should be used for this purpose). " Can anyone elaborate on...
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    Receiving Hisense TV IR signals. Is this possible?

    Hi all, Is there a way for any type of picaxe to receive Hisense volume IR commands? I know the irin command receives "Sony" commands but is there maybe a tricky way to get other brands of remote control to work? I only need to receive two buttons from a Hisense TV remote. Volume up and...
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    external resonator on 28x2 chip

    Hi all, I purchased a 64Mhz resonator, and installed it on my 28x2 picaxe. I used setfreq em64 command in the editor. It accepted a download and it works. But then I remembered that the chips have a 4x PLL phase lock loop and I SHOULD have installed a 16Mhz resonator instead. From the manual...
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    Serial graphing program

    Hi all, I have 8 ADC channels sending a serial string out to the PC. It all works well through the terminal program. Has anyone heard of or found a (free) program that can plot the 8 values on a moving real time graph?
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    12c communications

    Hi all, I'm working on having two picaxe chips (20x2) communicate with i2c. Things are going well but I have a problem. The master runs this demo code (the final product will have 8 different variables that will change depending on some other sensors): b1=1 b2=2 b3=3 b4=4 init: hi2csetup...
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    i2c pullups

    Hi all, I want to use a 5V picaxe with a 3.3v i2c device. If I set the pullup i2c resistors to 3.3v instead of 5v I believe it should work. But I just wanted to make sure that the Picaxe works correctly in that it "pulls down" the line to communicate (as required by the standard), and never...
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    Can't download new program after setting setfreq M64

    Hi all, I have a program that is working fine in my Picaxe 20x2 but I can't update the program any more. The picaxe won't take a new download. After the setfreq M64 command, I immediately have a serrxd command. I think what is happening is that the processor is working so fast that it gets to...
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    ADC external comp pins

    Hi all, I want to use the comparator pins on a 40x2 chip for reading adc10 voltages using an external precision voltage source for best accuracy. The manual says the adcconfig Vref+ pin is A.3 and the Vref- pin is A.2, but in the picaxe pinouts section here...
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    HX711 load cell connecting to Picaxe

    Hi all, I've ordered a HX711 load cell ADC for a strain gauge I wish to measure. I believe I have to use the hspiin and hspiout commands or maybe the shiftin shiftout commands, but am not quite sure where to start. Has anyone used this chip before and could you share your code? From the manual...
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    1.5v voltage drop when powering 20ma load

    Hi all, I am running a 20ma laser diode directly from pin c.7 of a Picaxe 20x2. I have measured the current at 18ma. It works but there is a 1.5V drop at the pin while powering the laser. So the output is 3.5V instead of the expected 5V. The input to the picaxe is a stable 5V. Is this...
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    vref FVR and ADC10

    Hi all, Quick question: If while using a readadc10 command, I set the FVR to 1.024 Volts, and my input on the ADC pin happens to go over 1.024 volts (but less than VCC) I won't damage the picaxe right? It will just saturate the internal op-amp right? Just making sure!
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    simple volume control using floating pins

    Hi all, I am thinking of ways to implement digital volume control on a microphone amplifier in the simplest way possible. I am thinking of using say 4 or 5 picaxe pins, and connecting them DIRECTLY to the DC biased low line level audio signal through various resistor values. The program...
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    strange debug behaviour on 18M2

    I have been trying to chase down an issue in my programming. Not sure if I have found the bug yet but during my testing, I found something strange going on with the DEBUG command. To see if my hardware is OK, I wrote a short program below.... as you can see, it polls the state of four inputs...
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    Servos..... (quick question??)

    Hi all, I have some very simple code running on an 08M: moveservo: wait 1 'high 2 wait 1 servo 0,200 wait 1 servo 1,100 wait 1 goto moveservo If I run the code as-is, the servo pulses are continuous, and the servos are held in position. If I "un comment" the third line "high 2" the servos...
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    Submarine camera for very deep water photography.

    So to preface, in 2006 I launched two high altitude weather balloons equipped with cameras, Picaxe, GPS and UHF radios. I tracked them from Melbourne, Victoria to the NSW border. It was a great little project, and a few people got involved along the way. Now I am thinking of doing some deep sea...
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    Serial to RS485 problems

    Hi all, I have built a network of picaxe 14M chips that communicate between each other through a MAX487 RS485 chip. They all work nicely and I can "see" the messages being sent and received using a terminal program. However, when I use a PC to send an instruction through the 485 bus, the...
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    24 channel temp logger

    Hi all, It's been a while since I posted last! Still see many of the "old guys" here.... I'll get straight into it: I have a project where I have to log 24 separate temperature points every 5 seconds or so..... So I am thinking 24 x DS18B20 and a 40X2 would work.... with serout to a serial...
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    need advice on sensing buried cable robot

    So we are building a house that needs a septic system installed, which involves sub-surface irrigation pipes, and a grass field that must be mowed regularly. (17metres x 18metres) I want to build a lawn mower robot ;-) , to mow the lawn automatically. At this stage we are laying the sub surface...
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    timeout doesn't work

    Hi all, It's been a long time since I've posted on the forum! I've just picked up a 08M2 for the specific feature of it having a serial timeout but it does not seem to be working for me. Here is a simple program: main: serin [1000,continue],3,N600,("ll"),b1 goto main continue: debug goto main...
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    Calculating checksums for serial communication (yuk!)

    OK coffee out and head scratching begin. This is a tough one, and I would really appreciate any feedback at all. I'm trying to get my head around getting the picaxe to calculate checksums for a bit of hardware I am designing. The Picaxe will be controlling an observatory dome and will be...