i2c bus hangs in master RPi access to MSP430G uC ~1 in 1000 accesses





.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ margin-bottom:0;
}







3















... resetting the MSP430 clears the hung state. I've slowed down the i2c clock freq, beefed up the PSupply, changed pull-up resistors - no change. However I made the "errors" increase significantly by busying the ARM with 2 calculation-intensive programs. I use Python in RPi, using smbus, SMBUS and
i2c_LCD_driver and try/except routines in the RPi to catch the bad access and reset the MSP - after that, accesses every 5 seconds continue fine until the next hang, ~1000 accesses later. I use C for the ISRs to manage interrupts in the MSP430.



I know both devices have hardware state machines that manage the i2c. Given that I can hang the bus by overworking the RPi, my suspicion was/is the implementation of the canned i2c python code. Is anyone aware of any weird
stuff about the Broadcom Serial Controller (BSC) i2c controller in the ARM that would hang a slave's state machine based on busy-ness of the OS managing the BSC ... or other cases of very intermittent bus hangs ?









share







New contributor




JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.



























    3















    ... resetting the MSP430 clears the hung state. I've slowed down the i2c clock freq, beefed up the PSupply, changed pull-up resistors - no change. However I made the "errors" increase significantly by busying the ARM with 2 calculation-intensive programs. I use Python in RPi, using smbus, SMBUS and
    i2c_LCD_driver and try/except routines in the RPi to catch the bad access and reset the MSP - after that, accesses every 5 seconds continue fine until the next hang, ~1000 accesses later. I use C for the ISRs to manage interrupts in the MSP430.



    I know both devices have hardware state machines that manage the i2c. Given that I can hang the bus by overworking the RPi, my suspicion was/is the implementation of the canned i2c python code. Is anyone aware of any weird
    stuff about the Broadcom Serial Controller (BSC) i2c controller in the ARM that would hang a slave's state machine based on busy-ness of the OS managing the BSC ... or other cases of very intermittent bus hangs ?









    share







    New contributor




    JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.























      3












      3








      3


      1






      ... resetting the MSP430 clears the hung state. I've slowed down the i2c clock freq, beefed up the PSupply, changed pull-up resistors - no change. However I made the "errors" increase significantly by busying the ARM with 2 calculation-intensive programs. I use Python in RPi, using smbus, SMBUS and
      i2c_LCD_driver and try/except routines in the RPi to catch the bad access and reset the MSP - after that, accesses every 5 seconds continue fine until the next hang, ~1000 accesses later. I use C for the ISRs to manage interrupts in the MSP430.



      I know both devices have hardware state machines that manage the i2c. Given that I can hang the bus by overworking the RPi, my suspicion was/is the implementation of the canned i2c python code. Is anyone aware of any weird
      stuff about the Broadcom Serial Controller (BSC) i2c controller in the ARM that would hang a slave's state machine based on busy-ness of the OS managing the BSC ... or other cases of very intermittent bus hangs ?









      share







      New contributor




      JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.












      ... resetting the MSP430 clears the hung state. I've slowed down the i2c clock freq, beefed up the PSupply, changed pull-up resistors - no change. However I made the "errors" increase significantly by busying the ARM with 2 calculation-intensive programs. I use Python in RPi, using smbus, SMBUS and
      i2c_LCD_driver and try/except routines in the RPi to catch the bad access and reset the MSP - after that, accesses every 5 seconds continue fine until the next hang, ~1000 accesses later. I use C for the ISRs to manage interrupts in the MSP430.



      I know both devices have hardware state machines that manage the i2c. Given that I can hang the bus by overworking the RPi, my suspicion was/is the implementation of the canned i2c python code. Is anyone aware of any weird
      stuff about the Broadcom Serial Controller (BSC) i2c controller in the ARM that would hang a slave's state machine based on busy-ness of the OS managing the BSC ... or other cases of very intermittent bus hangs ?







      i2c





      share







      New contributor




      JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.










      share







      New contributor




      JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.








      share



      share






      New contributor




      JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      asked 1 hour ago









      JoeMJoeM

      161




      161




      New contributor




      JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.





      New contributor





      JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






      JoeM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






















          1 Answer
          1






          active

          oldest

          votes


















          1















          I've slowed down the i2c clock freq




          I am using RPi3B+ stretch 2019apr python 3.5.3.



          I surprisingly and sadly experienced, and read that Rpi3B+ stretch python 3.5x I2C is buggy.



          I could never have slowed down the default I2C 100kHz. I tried to change speed up to 400kHz and down to 50kHz. But hardware did not respond - no nothing changed. :(



          I read that it is a hardware bug. Are you sure you have actually successfully changed the speed? I vaguely remember that I could indeed change the speed when I was in jessie or earlier days.



          I also found that python 3.5.3 block read does not fully implement to entertain all the parameter patterns. My projects were "hung" and much time wasted. :(



          I am anxiously waiting for the coming soon Rpi4 to hopefully resume my couple of long stalled I2C related projects. In the meaning time I am switching to SPI (I2C MCP23017 to SPI MCP23S17, etc)



          References



          RASPBERRY PI3 I2C BAUD RATE SETTING Postby samtal » 2018-Aug-04 Sat 1:45 pm



          / to continue, ...






          share|improve this answer


























            Your Answer






            StackExchange.ifUsing("editor", function () {
            return StackExchange.using("schematics", function () {
            StackExchange.schematics.init();
            });
            }, "cicuitlab");

            StackExchange.ready(function() {
            var channelOptions = {
            tags: "".split(" "),
            id: "447"
            };
            initTagRenderer("".split(" "), "".split(" "), channelOptions);

            StackExchange.using("externalEditor", function() {
            // Have to fire editor after snippets, if snippets enabled
            if (StackExchange.settings.snippets.snippetsEnabled) {
            StackExchange.using("snippets", function() {
            createEditor();
            });
            }
            else {
            createEditor();
            }
            });

            function createEditor() {
            StackExchange.prepareEditor({
            heartbeatType: 'answer',
            autoActivateHeartbeat: false,
            convertImagesToLinks: false,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: null,
            bindNavPrevention: true,
            postfix: "",
            imageUploader: {
            brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
            contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
            allowUrls: true
            },
            onDemand: true,
            discardSelector: ".discard-answer"
            ,immediatelyShowMarkdownHelp:true
            });


            }
            });






            JoeM is a new contributor. Be nice, and check out our Code of Conduct.










            draft saved

            draft discarded


















            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fraspberrypi.stackexchange.com%2fquestions%2f96748%2fi2c-bus-hangs-in-master-rpi-access-to-msp430g-uc-1-in-1000-accesses%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown

























            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            1















            I've slowed down the i2c clock freq




            I am using RPi3B+ stretch 2019apr python 3.5.3.



            I surprisingly and sadly experienced, and read that Rpi3B+ stretch python 3.5x I2C is buggy.



            I could never have slowed down the default I2C 100kHz. I tried to change speed up to 400kHz and down to 50kHz. But hardware did not respond - no nothing changed. :(



            I read that it is a hardware bug. Are you sure you have actually successfully changed the speed? I vaguely remember that I could indeed change the speed when I was in jessie or earlier days.



            I also found that python 3.5.3 block read does not fully implement to entertain all the parameter patterns. My projects were "hung" and much time wasted. :(



            I am anxiously waiting for the coming soon Rpi4 to hopefully resume my couple of long stalled I2C related projects. In the meaning time I am switching to SPI (I2C MCP23017 to SPI MCP23S17, etc)



            References



            RASPBERRY PI3 I2C BAUD RATE SETTING Postby samtal » 2018-Aug-04 Sat 1:45 pm



            / to continue, ...






            share|improve this answer






























              1















              I've slowed down the i2c clock freq




              I am using RPi3B+ stretch 2019apr python 3.5.3.



              I surprisingly and sadly experienced, and read that Rpi3B+ stretch python 3.5x I2C is buggy.



              I could never have slowed down the default I2C 100kHz. I tried to change speed up to 400kHz and down to 50kHz. But hardware did not respond - no nothing changed. :(



              I read that it is a hardware bug. Are you sure you have actually successfully changed the speed? I vaguely remember that I could indeed change the speed when I was in jessie or earlier days.



              I also found that python 3.5.3 block read does not fully implement to entertain all the parameter patterns. My projects were "hung" and much time wasted. :(



              I am anxiously waiting for the coming soon Rpi4 to hopefully resume my couple of long stalled I2C related projects. In the meaning time I am switching to SPI (I2C MCP23017 to SPI MCP23S17, etc)



              References



              RASPBERRY PI3 I2C BAUD RATE SETTING Postby samtal » 2018-Aug-04 Sat 1:45 pm



              / to continue, ...






              share|improve this answer




























                1












                1








                1








                I've slowed down the i2c clock freq




                I am using RPi3B+ stretch 2019apr python 3.5.3.



                I surprisingly and sadly experienced, and read that Rpi3B+ stretch python 3.5x I2C is buggy.



                I could never have slowed down the default I2C 100kHz. I tried to change speed up to 400kHz and down to 50kHz. But hardware did not respond - no nothing changed. :(



                I read that it is a hardware bug. Are you sure you have actually successfully changed the speed? I vaguely remember that I could indeed change the speed when I was in jessie or earlier days.



                I also found that python 3.5.3 block read does not fully implement to entertain all the parameter patterns. My projects were "hung" and much time wasted. :(



                I am anxiously waiting for the coming soon Rpi4 to hopefully resume my couple of long stalled I2C related projects. In the meaning time I am switching to SPI (I2C MCP23017 to SPI MCP23S17, etc)



                References



                RASPBERRY PI3 I2C BAUD RATE SETTING Postby samtal » 2018-Aug-04 Sat 1:45 pm



                / to continue, ...






                share|improve this answer
















                I've slowed down the i2c clock freq




                I am using RPi3B+ stretch 2019apr python 3.5.3.



                I surprisingly and sadly experienced, and read that Rpi3B+ stretch python 3.5x I2C is buggy.



                I could never have slowed down the default I2C 100kHz. I tried to change speed up to 400kHz and down to 50kHz. But hardware did not respond - no nothing changed. :(



                I read that it is a hardware bug. Are you sure you have actually successfully changed the speed? I vaguely remember that I could indeed change the speed when I was in jessie or earlier days.



                I also found that python 3.5.3 block read does not fully implement to entertain all the parameter patterns. My projects were "hung" and much time wasted. :(



                I am anxiously waiting for the coming soon Rpi4 to hopefully resume my couple of long stalled I2C related projects. In the meaning time I am switching to SPI (I2C MCP23017 to SPI MCP23S17, etc)



                References



                RASPBERRY PI3 I2C BAUD RATE SETTING Postby samtal » 2018-Aug-04 Sat 1:45 pm



                / to continue, ...







                share|improve this answer














                share|improve this answer



                share|improve this answer








                edited 2 mins ago

























                answered 21 mins ago









                tlfong01tlfong01

                832312




                832312






















                    JoeM is a new contributor. Be nice, and check out our Code of Conduct.










                    draft saved

                    draft discarded


















                    JoeM is a new contributor. Be nice, and check out our Code of Conduct.













                    JoeM is a new contributor. Be nice, and check out our Code of Conduct.












                    JoeM is a new contributor. Be nice, and check out our Code of Conduct.
















                    Thanks for contributing an answer to Raspberry Pi Stack Exchange!


                    • Please be sure to answer the question. Provide details and share your research!

                    But avoid



                    • Asking for help, clarification, or responding to other answers.

                    • Making statements based on opinion; back them up with references or personal experience.


                    To learn more, see our tips on writing great answers.




                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function () {
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fraspberrypi.stackexchange.com%2fquestions%2f96748%2fi2c-bus-hangs-in-master-rpi-access-to-msp430g-uc-1-in-1000-accesses%23new-answer', 'question_page');
                    }
                    );

                    Post as a guest















                    Required, but never shown





















































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown

































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown







                    Popular posts from this blog

                    What other Star Trek series did the main TNG cast show up in?

                    Berlina muro

                    Berlina aerponto