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Obviously, the drawRGBBitmap function is not implemented in ST7735_t3. As a beginner, I felt a bit overwhelmed, but I copied the functions from the Adafruit_GFX and copied them into the ST7735_t3. Now I actually get a coloured bitmap image on my small display. Perhaps the creators of the...

I would like to display a colour image on a 1.8' 160x128 display. The display works and is in colour. However, I don't know how to upload a colour bitmap image. The function I used throws an error. See the screenshot

thank you

How can I address the onboard LED using code, is it bound to a pin?

Thank you for your detailed thoughts and suggestions.

I am now quite satisfied with the development of my spectrometer. The program examples that I found here or on the Internet didn't help me much because I didn't understand most of them. I don't read out the chip's pixels linearly because I couldn't do this at the speed specified by the chip...

Yes, that's right, the button will take you to your website. There, quite far down in the history section, you will find the information about version 1.58: Updated toolchain to gcc 11.3.1 for Teensy LC, 3.x, 4.x Thank you

In version 1.58.1, the hardware versions 4 and 4.1 are not mentioned in the info. While they are mentioned in the version history. Which one should I use for a 4.1?

Because I tried this: https://forum.pjrc.com/threads/52569-TCD1304-with-teensy-3-2 He had tried to use the fastest way to read out the ADC As you have already read in my question: https://forum.pjrc.com/threads/73676-USB-Timer-AnalogRead-Interrupt I get strange effects when I use my program...

Thank you for the clarification. And how can I translate this information into Teensy 4.1?

I understand it to be an indication of the ADC. But with my Teensy 4.1 I get the message that: 'ADC0_RA' was not declared in this scope; did you mean 'ADC1_R6'. I want to use pin A8. Where does the result for A8 come from in this function? Could someone please explain this function to me...

I now have another strange effect on my project. I have the generation of pulses under control, but the readout still gives me problems. I can send the data to the serial (USB) port, there everything is still ok. But as soon as I actually read on the other side of the port, my pulse generation...

It is true: I ran two tests again. Once with the ADC library and once without it. The ADC library omits some values. Without the library all values come through. Who is responsible for this library, is there a error reporting web page? Or a newer version? These are the missing values: 63 127...

That's interesting, of course. However, it would then be the case that my ADC measurement is interrupted prematurely, and therefore the decisive bit was not read. However, I would not like to use delay. Is this a hardware problem, or a kind of library problem?

I had written my own VB program to display the point cloud, which I plan to use to display the spectrometer data. However, I then had the data entered in a list box, from which I then imported the data into Excel via C&P. There I then looked at the distribution. That means you are also missing...

I noticed the thing during my spectrometer tests, because I create a point cloud so far. Over the whole width of the representation these interruptions were to be seen. Afterwards I looked at these data statistically, and found out that these lines are always in the distance of about ? 64 units...

The noise generator should have an impedance of 50 ohms. I would accept a non-linearity of the ADC, because this could be corrected. Also a somewhat slow calculation could be compensated by waiting. But that certain bits (2^6) are out is a more serious problem. Would you please check the...

I have made measurements with the built-in ADC. When I displayed the data graphically, I noticed that certain values are missing or are displayed as "0". Interestingly these values are in the binary-typical distance of 64 to 65. Possibly it is a quantization problem. The following measured...

Yes, I had seen this post before. But unfortunately I am quite a beginner when it comes to C++ and Teensy. For this reason I don't understand the program described there at all. I could possibly copy it, but I would not learn anything from it.

Thanks @PaulS. I just hooked my analog oscilloscope to the signal and I don't see any interruptions in the voltage. I actually hadn't thought of the effect you mentioned here. My digital Osci should have Bandwidth: 100 MHz Channels: 4 CH Real time sampling rate: 2 GSa/s Capture rate: 120,000...

What is wrong with my code. I noticed strange effects on the oscilloscope. With a period of several seconds my clock signal breaks down. I noticed this only by chance, normally I didn't pay attention to such late signals at all. No matter if I toggle the output or set it HIGH or LOW...

The loop() function also returns nothing, so it is void. Or what do you mean?

Thank you, I will try this again. As far as I remember I had already tried to do the AnalogRead in the void loop. I will try that with the flag.

If I can't generate the signals with the Teensy without being disturbed, I guess I have to use an external generator. #include "TeensyTimerTool.h" #include <ADC.h> ADC *adc; using namespace TeensyTimerTool; static int cnt = 0; // ticks of clock static int diode = 0; // index...

I have now made a few tests with the three methods. Unfortunately I always get disturbances from 130µs on, as soon as AnalogRead is called. Yellow is the disturbed clock signal

This is what I have so far. With a VB.Net test program I can actually already see the data of the photodiodes and display it as a curve. Unfortunately, the AnalogRead function is so slow, that at the moment I only read every 16th diode, and on the next pass the next diodes. Always in the...

Thank you.

6 bit would be too little for me. 10 bit could be enough for the time being. I have 3648 active photodiodes. These are read 135 times analog within one second. But if I take the triple because of the sampling theorem, I come to 405Hz. So 3648 photodiodes with 405Hz results in about 1.5 million...

Until now, we had not talked about the performance of the laser at all. Whether 100mW is needed or not, we will see. Imagine you are looking at a piece of fabric. For you it has the color green. That is what you can see with a 7341. And that's fine, of course. But if you want to know how the...

Yes, I still think about that. As I said, it would be a dream to get a direct live measurement of the spectrum. Using a stepper motor to rotate the grating would be possible, but the mechanical effort in that case would of course be much greater. I work in a chemical laboratory with different...

First, of course, it would be great if I could get a spectrum at all. My dream is a Raman spectrometer, with which I would be able to analyze surfaces of plastics, for example. If such a device could be produced as a DIY in a small format, it would certainly be an interesting possibility for...

Thank you, to all who have already participated here. I think I could save a lot of transmission volume anyway, especially when it comes to data from a spectrometer, if I only send what has really changed. So similar to the compression with films or photos, if one always sends only the address...

And do you know how to receive this 480Mps on PC side? Do I have to go through Windows APIs to get it?

It is possible that the speed will be quite sufficient for this project. However, my question is also to be understood in general. "So which would be the fastest method to transfer data?" VB.Net is simply because I have been working with it for many years, at least at my workplace. At home, of...

Sure, that would be great if I could transfer data that quickly, of course. But now it is often the case that you would also have to receive this data accordingly on the PC side. Are there any drivers that I could use from VB.Net. So far I have only worked with the serial interface on the PC...

Since I want to build a spectrometer, I also want to display the data nicely on my PC. I don't want to burden the Teensy with such work, to control a display whose resolution and other performance would not be very comfortable anyway. I find the normal serial baud rates quite antiquated. My...

For my TCD1304DG experiments I am testing the speeds of the ADC measurements. I have now used the simplest ADC method, analogRead inside the void loop. I was surprised that the processor clock rate has almost no influence on the sampling frequency. I have a toggle output for my osci before and...

Danke @luni

Thank you.

Are you the @luni who wrote the TeensyTimerTool.h? Thank you, for your contribution. You are right, I should try to create the second pulse in the interupt routine, then it is synchronized right away. The signal gets harmonics, but they still remain acceptable. Do you want to tell me what your...

@joepasquariello Perhaps I had misunderstood you. All I found useful under the term QuadTimer was this timer library. That's why I thought that you could program the internal timers of the processor to run synchronously at 2MHz. But now I understand you to mean that I should get external timer...

You're right, I hadn't realized it was float. 2MHz seems to be the maximum. How can I achieve synchronization. Wouldn't I have to start the timers at the same time? Is that possible if I create them as an array? As soon as I use two timers, with their own interupts, the signal becomes...

I have tried the TeensyTimerTool.h now. With it I get just 500KHz. Can I still turn something at the timer configuration, so that I come to higher frequencies? The signal looks clean, but what would you expect at 500KHz? #include "TeensyTimerTool.h" using namespace TeensyTimerTool; int fMPin...

As I mentioned above, I want to read out a TCD1304DG. This is a linear image sensor. I want to build a spectrometer from it. The optical parts are available to me. I haven't made a decision yet on which ADC I would use. For example, I don't know yet up to which sampling rate the Teensy's...

Thank you @joepasquariello for responding. I will look at your suggestion with the interval timers I have now also experimented with different clock speeds and it is indeed the case that the faster the processor runs, the more stable values I get. I think I need a cooler. Now to get an analog...

Hello This is my first post. I am rather a beginner in the microcontroller world, also have little experience with C++, having only used VisualBasic up to VS2019, as well as assembler (many years ago). I am currently trying to control a TCD1304DG. Using the delay commands worked quite well...