Recent content by Goeytex

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    Flux left on circuit boards

    I suspect that scraping the flux off removed a tiny solder bridge on the board. It is unlikely that the flux itself could carry enough current to fully turn on a transistor at relatively low switching speeds. That being said, it is still a bad practice ( unprofessional) to leave flux on a...
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    Code to control output On and Off pulse times with pots

    Yes, a complete and detailed description of the project is necessary in order for anyone to provide good advise. Honestly, I see no way with a single Picaxe to to measure flywheel velocity and to use that data as feedback to precisely regulate the speed of a BLDC motor, assuming...
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    Code to control output On and Off pulse times with pots

    Two Questions 1. What are the minimum and maximum RPMs that you need to measure? 2. What type of motor is turning the flywheel ? BLDC 1 or 3 phase? A Picaxe is limited to WORD variables . So Assuming a chip frequency of 8MHz, Pulsin will time out and return a zero after 65535 * 5 us (...
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    Code to control output On and Off pulse times with pots

    Are you building an ignition controller or an RPM limiter? If you are I have some Picaxe code that may interest you. Let me know and I will dig it out. of my archives. Counting revolutions is a slow and fairly inaccurate way of measuring RPM. By the time you count enough revolutions to get...
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    AXE027 alternate

    You have a device with a fake FTDI chip. The fakes have an OTP ROM and cannot be programed with FTPROG. This is not because FTPROG does not support programming these fakes intentionally. It is because the fakes either have a read only (ROM), or they use a completely different method of...
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    My brain is fried... a wireless network

    One the members here, "srnet" put a Picaxe and an RF22 on a Cubesat. It reliably transmitted data from earth orbit. I have used Si4432 modules with Picaxe. These use SPI to communicate between the microcontroller and the RF module and can be a bit tricky to configure. The range...
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    Other options to wirelessly program PICAXE?

    Wireless programming can be tricky with a Picaxe ( Or any other Microcontroller). With the Picaxe, it requires RF modules that act as a transparent UART and that also support break signaling. Since ERF modules are no longer available the choices are slim. I have had wireless programming...
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    4-20mA project

    My guess is that you do not have the grounds for the separate supplies tied together. Run a wire from the Pot's ground side directly to Picaxe 0V Pin. ( I would recommend a 10K Pot instead of a 1K) Measure the voltage from the Picaxe 0V Pin to PinC.1. While turning the POT full range...
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    Higher Wattage 12v Card LED strobe unit

    Attached is a example diagram of how I would do it. I have used Dual Mosfet drivers and low RDSOn FETS. This gives superior performance and efficiency. However, if you only need to turn the LED's on and off occasionally then you can get by without the Mosfet drivers and can use Logic Level...
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    ASCII Characters in sertxd Output ?

    Since you did not say, I am guessing from a previous post that you are using a Picaxe 18M2 If you cannot figure out a way to place the suggested resistor, then you might try placing a "Low C.3" as the very first line of the program. This will set the sertxd Pin as an output and make it low...
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    N38400_32 BaudMode between 18M2 and 20M2 with qualifier

    The diagram below may help a bit for checking baudrate. Have the Picaxe send two bytes ("UU") or (85,85) and then measure per the diagram below. #Picaxe 18M2 Setfreq M32 Low C.6 '// Make Serout Pin as output and set low Do Serout C.6, N38400_32,(85,85) pause 16 '// 2 ms...
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    Reading a negative voltage with ADC

    Here's an idea that should not be too painful. Make a patch cable as diagrammed below.
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    Doing Work for Students

    I just got a private message from a complete newcomer offering to pay me for writing the Picaxe Basic code for a school project for him and his group. He indicated that the project would be going to exam. Here was my reply If you are contacted, I suggest you reply in a similar manner.
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    Controlling 12v circuit from a high or low pin

    See Attached for diagram EDIT: Changed FET to TO-220 through-hole type for easy mounting.
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