I've looked at the datasheet but never worked with this chinese IC. As is written, "100pF is used to reduce radio interference to communication ports".
The values of the pull-up resistors and the capacitor are influencing the rising and falling edges of the CLK and data signals. If capacitors are bigger, the rising time will be longer. When such a requirement appears in a datasheet, it might be a problem of oscillations on the bus which can be reduced by placing capacitors, but not necessarily to be so. You have to check with a scope if your bus looks well or not. The connection length between IC and your microcontroller may be important. So, if you do not have a software problem ( which is most plausible to be) try to use twisted wires clk+gnd, dio+gnd without 100pF capacitors and 10K pullups near the TM1637. Reducing the pullup to 5k1 may help. On Tue, Jul 5, 2022 at 7:35 PM [email protected] <[email protected]> wrote: > > Hi Rob, > > Thanks for that quick answer. I will try with and without those > capacitors, but it is still strange that they appear to be mandatory if you > red the datasheet.... > Anyway, thanks, and I'll keep you posted > > Kind regards, > > David > Le mercredi 29 juin 2022 à 19:31:29 UTC+2, [email protected] a écrit : > >> Hi David, >> >> I do not remember anymore but I think I read it somewhere. I do see in >> the init function that there are pull-up resistors on the module and if you >> also have capacitors on those line that may impact the speed. >> >> I did find this which also says that the capacitors may impact the speed. >> >> >> >> You can try if it works with or without the capacitors. >> >> Kind regards, >> >> Rob >> >> >> >> ------------------------------ >> *Van:* [email protected] <[email protected]> namens >> [email protected] <[email protected]> >> *Verzonden:* woensdag 29 juni 2022 16:42 >> *Aan:* jallib <[email protected]> >> *Onderwerp:* [jallib] Re: Lirary for TM1637. >> >> Hi Rob and all, >> >> I wonder about the comment in the header of the lib stating that the >> capacitors on DIO and CLK lines should be removed from the modules, while >> the TM1637 datasheet mentions that two 100 pF should be placed on those >> lines. >> Why whould I need to remove them ? >> >> Thanks for your opinions, and have a nice day >> >> David >> >> Le samedi 27 juin 2020 à 15:57:32 UTC+2, [email protected] a écrit : >> >> Hi all, >> >> I created a library for the TM1637. >> >> For more info (with video) see: >> http://www.justanotherlanguage.org:3389/node/320 >> >> The library will be available in the next bee package. >> >> Kind regards, >> >> Rob >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jallib" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/jallib/71f26cac-ce26-4306-a622-362df6abe10en%40googlegroups.com >> <https://groups.google.com/d/msgid/jallib/71f26cac-ce26-4306-a622-362df6abe10en%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/jallib/447d9b4b-726f-4b6c-ab12-9d0af76794f4n%40googlegroups.com > <https://groups.google.com/d/msgid/jallib/447d9b4b-726f-4b6c-ab12-9d0af76794f4n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "jallib" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jallib/CAM%2Bj4qvM8%3D_cLeoUfzEbzghfW3jVAdZg-S4G0qtNTzJ3mOjecg%40mail.gmail.com.
