kd5rxt-mark

The I/O pins on the Teensy 4 are not 5VDC tolerant as inputs (3.3VDC max input level without causing damage), & only put out a nominal 3.3VDC as outputs. Most of the "Arduino compatible" relays require a 5VDC level signal to drive them, so...

Did you consider filing a bug report with Arduino ?? Mark J Culross KD5RXT

@Dsolberg8132: The following should work better (note changes in BOLD - sorry for the lack of formatting . . . can't do color/bold inside of CODE tags !!): switch (msg.buf[1]) { case 0x75: output_voltage = (msg.buf[6] * 256 +...

@ctadlock: I don't know what "that guy" is that you refer to. You asked a question (how does the bootloader chip distinguish ??), and the answer (by the FLASH size) is actually provided in several different forms & in several different places...

That page references the thread where development of the bootloader chip was discussed (you did read that thread, right ?!?!?). The definitive method of distinguishing between T4.0, T4.1, & TMM can be found in <Post #200>. Hope that helps . . ...

As I understand it, if you use a smaller FLASH, then it simply would not be a T4.1. Mark J Culross KD5RXT

@ctadlock: @jmarsh gave that answer in <post #2> above. Mark J Culross KD5RXT

@IWantYourCookies: I would suggesst that you add a line to your setup() function something like this (which will wait for a maximum of 3 seconds for the serial monitor to be connected, then proceed): while (!Serial && millis() < 3000) {}. Then...

@Dsolberg8132 (Don K9AQ): I don't know if it will help you directly, but take a look at <this> post, specifically the can_sniff_RX_isotp() function for ideas on how to access the data bytes in an extended frame. That particular sketch was...

According to <this> file (which provides the CAN protocol for the Huawei R4875G1), the 0x1001117E status is as follows: This is an unsolicited message reporting the DC current, encoded in the last four bytes Maybe the function of this...

@Dsolberg8132: Glad to be able to help a little every now & then. Mark J Culross KD5RXT

@Dsolberg8132: If you look in the FlexCAN_T4.h file, the definition of the CAN_message_t appears as follows: typedef struct CAN_message_t { uint32_t id = 0; // can identifier uint16_t timestamp = 0; // FlexCAN time when message...

@jerryk: Without seeing specific examples and/or information showing where you placed your syntax errors, there are a few very likely possibilities: 1) make sure you are modifying the correct usb_inst.cpp file a) there are separate core...

Translate P#24: This thread is the best place to sell an unused Teensy 3.2 because the updated link on the Teensy 3.2 page is here.I added a new update about your 100 leftover boards. Hope it helps you and anyone who still needs to find an extra...

@stellartom: Are you using the Arduino IDE to compile your sketch ?? If so, what "USB Type:" are you selecting in the "Tools" menu ?? Mark J Culross KD5RXT

@loopstudio: It is almost impossible to help without a few more details. - which example(s) did you find ?? - can you post the sourcecode for the sketch that you are using ?? - can you post pictures of your hardware ?? - which Teensy version are...

@charnjit: I was able to successfully compile your code here (Arduino IDE 1.8.19 + TD1.60b1 & Arduino IDE 2.3.4 + TD 0.60.1), with either "Serial + MIDI" or just "MIDI" selected as the "USB Type" & T4.1 as the "Board:". I did comment out the...

@HopWorks: Since you are planning to make use of the T4.1, you might want to use the T4.1's onboard microSD socket in place of adding an external SD card reader. The onboard interface should be much faster & would have the additional benefit of...

@Known_me: Are you implementing this on a Teensy ?? This forum is for the discussion and support of the Teensy family of products. If you are using strictly MATLAB, your question might be more appropriately posted on their forum. Mark J...

The example sketch TimeTeensy3 has information that should be what you are looking for. Note that the current time also gets sent by your PC to the Teensy every time you download your code. Mark J Culross KD5RXT

@Steve_AU: Have you seen <this> posted write-up on using DMA on the Teensy 4 ?? The post is from a few years back, but should still be pertinent. You may want to browse the entire thread for more details as well. Mark J Culross KD5RXT

@Deftaudio: The "pure hardware" reference implied that the bodge wires would carry the signals from the mistaken pins to the intended pins (30 => 0, & 32 =>1), then you could use the normal MIDI calls to make use of the standard MIDI serial port...

I forgot to include the pertinent portion of my PCB schematic for reference. Mark J Culross KD5RXT P.S. Note that I am using MOSI1, MOSI1, CS1, & SCK1 on the T4.1, but that was to allow the RA8875 display & the Teensy Audio Adapter to be on...

@AJL Electronics: In my current TeensyMIDIPolySynth project, I make use of the TFTM070-5 from buydisplay.com (see spec below), which is connected to & driven by a T4.1. On my original wire-wrapped prototype of the project, the display worked...

@Thundercat: Not sure what you are referring to as "RF hash" (what would be the source of that, assuming you are talking about induced noise ??). In my current TeensyMIDIPolySynth (TMPS) project, I do, in fact, have MIDI OUT pin 2 connected to...

@JulienS: So, you would probably be safe to conclude that the Teensy is not UL certified. A quick Google search reveals that UL certification is reported as being very expensive. I am certainly not intending to speak in any way that might be...

Not sure which UL certification (https://www.factoredquality.com/resource/all-you-need-to-know-about-ul-certifications) you are specifically looking for & specifically why, but the three certifications that are listed for the Teensy 4.1 can be...

Check <this> thread for a similar discussion that might be what you are looking for (can't be sure that I understand your question correctly). Mark J Culross KD5RXT

Now that I'm back where I have access to my Teensy development environment, you can completely ignore all of my previous posts . . . as I suspected & forewarned, my earlier observations probably have absolutely nothing to do with whatever is...

Unlike the specific line that I referenced enum { cells = board * cell }; // board * celle, that line enum { packets = board * 16 }; // board * pacchetti is not a #define multiplied by a #define. Again, I admit that this may have absolutely...

Sorry, you did specifically reference "cores", & I completely glossed over that, mistakenly focusing instead on the "libraries" aspect. Mark J Culross KD5RXT

Is <this> what you are looking for ?? Hope that helps . . . Mark J Culross KD5RXT

I have no idea if this makes any difference at all and/or if this is in any way related to what you are experiencing, but the syntax on your "enum" declarations is not typical. Typically, the syntax is as follows: DECLARATION: enum...

@Akram: with the resistance value that you measured (a somewhat higher value, rather than a value close to 0 ohms) probably indicates the lack of a dead short, so that seems to be good. However, the fact that you measure no voltage out of the...

@Akram: Here are a few quick things to try (in this order): Have you checked for a short on the 3.3VDC power supply as described <here> ?? Have you measured the 3.3VDC supply when plugged into power ?? Did you try the <factory reset>...

Speaking strictly for myself (not intending to answer for Paul), do you realize how totally unrealistic (can't think of a better adjective at the moment . . . not enough coffee this morning) that your request really is ?? Paul's boot mechanism...

Check <this> older thread which may have some info that may be helpful to you. Mark J Culross KD5RXT

@jerryk: There's some discussion in <this> older thread that covers how to create a custom USB build type. Aparently, there is additional guidance in the core file which you will be editing to make it happen. Mark J Culross KD5RXT

@PeteH: The likelihood of anyone being able to help with troubleshooting goes up tremendously if you post your code (make sure to use the </> code tags to keep the readability of what you post intact). Without that, the best anyone can do is...

Excellent catch by @defragster !!

Continuing with suggestion #2 above, if you also declare an additional variable volatile unsigned long previous_end_of_int, then inside your interrupt function right after setting start_of_int to the current millis() value, copy end_of_int to...

Code ??

Here are a couple of quick possibilities to guage how long your interrupt function is taking to execute: 1) Toggle a GPIO pin on at the beginning of your interrupt routine and toggle it off at the end, then monitor that GPIO pin with an...

Take a look at <this> post & the other posts in the same thread . . . was addressing a different condition, but involved a similar discussion. Mark J Culross KD5RXT

@charnjit: For changing between & playing multiple WAV files, [ICODEAudioMemory(24);][/ICODE] seems low. Have you tried bumping up the amount of audio memory allocated ?? Have you tried adding a periodic call to AudioMemoryUsage(); &...

@Davidelvig: In my TeensyMIDIPolySynth (TMPS) project, I use the AudioAnalyzePeak (for example, naming it peak1) audio object, calling peak1.read() every 100ms to get the value. I know that I'm wasting some headroom by doing so, but I try to...

Back in the days of old (yes, I am that old), we used to use CD4066 digital switches to be able to route signals from anywhere to anywhere under microprocessor (8051 and/or 8085) control. I don't know what a modern-day equivalent of the CD4066...

Sorry for the long post, but I can assure you that its length is merely to fully convey a potential work-around to the inability to upload to the Teensy without pressing the PROGRAM button !! I occasionally have similar problems uploading to...

Maybe I'm missing something, or maybe I'm incorrectly over simplifying, but couldn't you just read the analog input & run that thru the map(val, in_min, in_max, out_min, out_max) function, where you set the in_min & in_max in your calibration...

@Scone2523: posting what you ended up getting to work may be beneficial to anyone else who may stumble across this thread in the future. Mark J Culross KD5RXT