Recent content by Circuit

  1. C

    Darlington Array connections to output devices

    This was a most helpful pointer; when I tried the TBD62083A back in 2017 I was so impressed by the improved performance that I swapped over to using them exclusively (and I am left with piles of unused ULN2803s - I think I have around fifty sitting in drawer!). I mainly use them for firing...
  2. C

    Use of RFID RC522

    The interface to the RC522 is straightforward; the code necessary to operate it is not. I have several RC522 now operational but not with PICAXE - which was my original intention - but with another system that is based on 32-bit PICs. It is quite a programming challenge to write PICAXE code...
  3. C

    Digital logic on noisy lines

    Oh dear, I need to rethink... Well that is an embarrassing schoolboy error indeed. Okay, rather than delete my enquiry with sheer embarrassment, how about if I keep the same idea but connect the 10 K pull-ups to 12 volts+ve? And, of course, pull-ups on the receiving PICAXE pins. (Crikey, I am...
  4. C

    Digital logic on noisy lines

    I need to send 8 lines of digital logic over some long wires; 20 to 100 metres perhaps, as part of a security system. PICAXEs will be at either end. The lines are in a domestic environment but may be passing a variety of other cables, mainly mains cables, washing machines and so forth, and...
  5. C

    08M2 EEPROM Life span

    Hence the parameter "Mean TIme Between Failures"...
  6. C

    Interrupt to non volatile memory

    A recent posting that covers some of these aspects with an input from Hippy on wiring and software; https://picaxeforum.co.uk/threads/08m2-eeprom-life-span.28641/ Edit; whoops! I see that you were asking a question there also.
  7. C

    08M2 EEPROM Life span

    Probably not directly useful to the questioner, but worth noting for others perhaps who may look to this issue; if there is a battery-backed DS1307 clock chip in the circuit then the RAM on that can be very useful for storing values between power-downs without fear of wearing the storage out as...
  8. C

    PICAXE Macros

    Hippy, that is a most welcome document - I have already reformatted it into an eight page .PDF and printed it as an A5 booklet, stapled and sitting on my desk ready for careful reading and further thought. Thank you for this excellent narrative. It would be excellent to see an update of the...
  9. C

    Logging Data from serial port

    As a true RS232 signal swings +/-15 volts I would clamp the input voltage to the PICAXE Vcc with a couple of diodes and limit the current with a resistor as follows; If you look in PICAXE manual 3 page 44 it shows the "PICAXE recommended" handling of RS232.
  10. C

    Starting a stepper motor project, need one question answered regarding travel limits

    I used Elements + and stacking with my Canon 5DIII before I bought the Panasonic ZD200 earlier this year. The focus stacking in the modified Photoshop works extremely well and this should serve you nicely; to work well, though, you need a pretty capable processor and lots of RAM otherwise the...
  11. C

    Starting a stepper motor project, need one question answered regarding travel limits

    The TMC2103 drive can do what you want - it detects stall currents and will report back to the PICAXE chip; the downside is the 103 page datasheet! This is a challenging little chip to choose if you want to use the advanced features. Stalling stepper motors against end-stops without stall...
  12. C

    Body diode in MOSFET

    I am proposing to switch 12V AC at around 500mA using this a PICAXE in this configuration; This involves using the body diode of the MOSFET to conduct and I find it difficult to get full specs on the body diode from many MOSFET datasheets. Clearly, the maximum current capability of the body...
  13. C

    Triggering PICAXE inputs with photointerrupters

    I need to use photointerrupters as limit switches on a PICAXE project. The ideal size of device for my project appears to be met by the GP1S094HCZ0F from Sharp. (datasheet- http://docs-europe.electrocomponents.com/webdocs/0d1b/0900766b80d1bdb9.pdf ). The sheet shows the wiring thus; I have...
  14. C

    H-Bridge design - is p-channel/pnp high-side switching advantageous?

    I am proposing to control a simple D.C. very low current (circa 50mA) motor with an H-Bridge controlled by four outputs from a 14M2 chip - no PWM, just on/off and direction. I want the whole thing rather compact and therefore I don't want to use half of an L293D, but just a simple H-Bridge with...
  15. C

    Newbie - assistance please - AXE118 Project Board

    Roger, if you look at your kit again you will see that a lot of it is self-explanatory. Firstly, look at the "contents" section of the datasheet that came with the kit. Here you will see the listing of the parts and some clues as to how to identify them; the resistors have coloured bands that...
Top