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  1. M

    Calculating integers far greater than 65535.

    Hi Marks, Thanks for your input with this project and your fancy code. BREAK OUT THE BEERS!!!! 🥳🥳🥳 Your code works an absolute treat! It is so accurate, that it is now necessary for me to proceed to creating the test PCB jig in order to confirm the accuracy of this circuit/setup to the...
  2. M

    Calculating integers far greater than 65535.

    Marks, AllyCat & Hippy, Thanks for that, yes, 'COMMON MODE' was previously mentioned and silly old Mort didn't trigger to it and take in Marks comments at POST #54. In a way this shows the difference of 35 years of mostly self education/research/asking questions online VS a formal education...
  3. M

    Calculating integers far greater than 65535.

    Hi All, For those of you playing along at home... The below readings were accurately taken with the original circuit modified for testing purposes with a 2.5V reference. 'This program takes 1000 samples from the LTC2485 and then provides the average values. Startup: #com 1 #terminal 4800...
  4. M

    Calculating integers far greater than 65535.

    Hi marks, Want to have a go explaining working down to 330 ohms from a MAX 24bit value being equal to 16,777,215 decimal? Regards, Mort.
  5. M

    Calculating integers far greater than 65535.

    I can't provide ACTUAL's atm. This is because the PCB has not been manufactured yet. To provide relative 'accurate' actual reads, I need to print and build this circuit to a PCB. Currently it is in 'better than usual' breadboard form, but still not at all good enough to provide a good ADC read...
  6. M

    Calculating integers far greater than 65535.

    As previously posted, the earlier values reported were incorrect with a number of factors not being accounted for. Since then, this circuit/setup and tolerances have been dramatically improved. The suggestion of R1 also being 330 ohms is valid, however this then presents an unacceptable current...
  7. M

    Calculating integers far greater than 65535.

    The theoreticals in a ‘perfect world’ 0.1ohms = ADC 1118 or %10001011110 or $45E and measures 0.00025VDC or 250uV 330.0 ohms = ADC 3,689,400 or %1110000100101110111000 or $384BB8 and measures 1.10VDC recurring. The resolution Is easily available to achieve 0.1 ohm steps. With R1 being 0.01%...
  8. M

    Calculating integers far greater than 65535.

    It is a 24bit value we are working with. Bit 5 of first byte through to bit 6 of 4th byte. The pair of 10k resistors at the ADC are not at all significant in the circuit or equations, but do need to remain there for protective purposes. Also, if anyone is interested (please speak up) I am...
  9. M

    Calculating integers far greater than 65535.

    Yes, sorry Hippy, I am pretty sure I have given you a bum steer with earlier values and took them without factoring in slight inaccuracies in R1=1K and R2 being 329.2 ohms measured. But, if you work with the theoretically accurate known values noted earlier, perhaps we/you can get to where I am...
  10. M

    Calculating integers far greater than 65535.

    The ADC values are essentially a ratio metric digital representation of a voltage. This particular project will only ever have a MAX R2 resistance of 330 ohms. Just to provide you an appreciation of this circuit/setup, theoretically a MAX decimal value of 24-bits is 16,777,215 (a far cry above...
  11. M

    Calculating integers far greater than 65535.

    Yes, they don’t add up to me either. Give me a few days and I will post again specifically providing new figures all round. ie Exact R values ADC’s etc. Regards, Mort.
  12. M

    Calculating integers far greater than 65535.

    And yes you are correct in your idea. The Code I wrote was more or less demonstrating what I thought was the right initial approach to the drama at hand. Regards, Mort.
  13. M

    Calculating integers far greater than 65535.

    Hi Hippy. Perhaps easy for you my friend. I am running out of hair :) Regards, Mort.
  14. M

    Calculating integers far greater than 65535.

    Hi, You are correct, however, if the routine continuously gets repeated... Regards, Mort.
  15. M

    Calculating integers far greater than 65535.

    I must have read that wrong. 8,333,034 / 3300 = 2525.16 (3300 0.1ohms in 330ohms) 6130 * 3300 = 20,229,000
  16. M

    Calculating integers far greater than 65535.

    If I understand what you are asking... 16,777,215 is MAX ADC value 6130 = 0.1ohms 8,333,034 = 330ohms. Reference to this... Init: HI2cSetup I2CMASTER, $48, I2CFAST, I2CBYTE main: hi2cin (b1,b2,b3,b4) sertxd("LTC2485: ",#b1," ",#b2," ",#b3," ",#b4,cr,lf) pause 200 'This brief delay is...
  17. M

    Calculating integers far greater than 65535.

    Ok... I have decided to go pretty extreme with this project and to put it bluntly, I feel I have now chewed off more than I can swallow (in the programming side of things). The ADC chip I have gone with is a LTC2485. A 24-bit ADC that returns a result via I2C. This chip is rather impressive...
  18. M

    HX711 load cell issues

    Hi, I would suspect reducing the gain should provide a different result even if it is incorrect. I am wondering why you have placed pull down resistors on the CLOCK and DATA lines? To confirm all is at least well from DATA out of the module, if you were to disconnect the DATA line from the...
  19. M

    HX711 load cell issues

    Hi, That is a mighty fine effort, being that you consider yourself a 'beginner programmer'. Good job! Regards, Mort.
  20. M

    Calculating integers far greater than 65535.

    Your code is pretty cool. Thanks for going to the effort, I genuinely do appreciate it. I am pretty sure (although still browsing the finer details of numerous datasheets, now inclusive of Hippy's suggestion of HX711) I am going to go with an external ADC. Thus far the MCP3421 in singled-ended...
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