Search results

  1. C

    Teensy 3.2 (and 3.1) occasionally not running on power up!

    I can confirm I've also seen a similar problem. In my case, the teensy 3.1 was mounted on a PCB, with 3.3V fed from a linear regulator (ST117 iirc) in turn fed from 5V from a MC34063 switching regulator, down from 12V DC. This came into the board via a typical 2A off the shelf AC/DC converter...
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    Teensy 4.0 I2S MIC Breaks FastLED

    Hi, I haven't yet used a Teensy 4, nor an I2S microphone, however, I have spent a lot of time debugging FastLED with audio library issues on Teensy 3. WS2813's (and family) have very strict timing requirements. In the normal running, FastLED will release control of the processor in between...
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    Teensy or Arduino?

    Hi, Put simply, the Teensy 4 is orders of magnitude faster than the Arduino Mega. It has more hardware resources available, faster clock speeds, more electronic interface options (SPI, I2C, UART, etc). If the Mega works for what you want to do, then there is not much need to change. But if you...
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    Teensy 4.1 and 2 x MAX31855 thermocouples SPI problem

    Can you verify with a DMM (preferably an oscilloscope) that the CS lines stay high? This certainly sounds like bus collision! The only other hardware issue I can think of, is that the MAX31855 isn't tri-stating the SPI lines (ie, it's pulling the lines high or low). With only the one IC, you get...
  5. C

    prevent RGB led from lighting up on boot up

    Try adding a pull-down resistor between the respective PWM pins, down to GND. 1k or so should be fine.
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    FastLED, WS2812b and UART Interrupts

    So this crossed my mind - the issue being that the calls to weren't running in an interrupt, so could be interrupted by anything. Based on that, I devised a work-around. I used an IntervalTimer to generate a software interrupt, and stuck in that (inheriting an...
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    FastLED, WS2812b and UART Interrupts

    Further investigation has revealed that (as I somewhat expected), it wasn't anything to do with the UART (this was merely a symptom of course). Stripping back my sketch, it appears the simple creation of an AudioOutputAnalog object is enough to cause the issue - I don't understand why though...
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    FastLED, WS2812b and UART Interrupts

    I've got a project receiving UART data on UART0 (Serial1) whilst driving a string of WS2812b's, using FastLED, on a Teensy 3.2. The UART runs at 460800 bps, I'm driving 15 LEDs. My understanding of the default timing of FastLED and WS2812b's is as follows: 1) Disable interrupts 2) Output data...
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    Pushing firmware to Teensy 3

    John, we also use T3.2 in a commercial product - this is something I have looked at but put it in the 'too difficult' pile (for now). If you do find any information or make any progress you're willing to share, please keep me posted! -- Iestyn
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    ILI9341_t3 font editor

    That's excellent! Really nice work. It's not too much trouble to build it, but not all users of Teensy will necessarily use Visual Studio, so may make it more accessible for those users.
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    NST3.2 (Not So Teensy 3.2)

    This sounds like a good idea - for hobbyists, they can be trusted with the switches, but speaking as a commercial user, I'd be worried that my customers can mess about with the switches (either accidentally or purposefully).
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    Teensy 4.0 (hypothetical) pin assignments

    It's too late in the day and my head is too fried to process the sheer quantity of trade-offs to make. But the only consideration I might suggest would be that whilst the new audio hardware signals (S/PDIF, Redundant I2S pins etc) are useful to some users, if you're not using the T4 for audio...
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    How to wirelessly interconnect Teensy devices?

    In which case, my recommendation would be an ESP32 or ESP8266 slaved to the Teensy, using MQTT. Will be more than capable of pushing those kind of rates out, with plenty of headroom and flexibility. Have a read into it; you will find you'll need a 'broker' of some description to host the system...
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    How to wirelessly interconnect Teensy devices?

    Hi there! You're right - there's a lot of options available. To try and narrow it down, a few questions: 1) What sort of data rates are you looking to push through the links? 2) How many devices are you trying to network? 3) Are these going on battery power? If so, what sort of standby power...
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    I want to use UART/USART with Teensy++ 2.0. But I'm beginner.

    Let's get this straight. Are you just wanting to have the PC send and receive serial data to the Teensy? If so, you need nothing more than the teensy itself and a USB cable; the teensy 'talks' USB serial and power is supplied through that cable.
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    Teensy 3.2 as FTDI programmer for ESP12E

    The ESP8266 can be a pain to program, with a teensy in-between or not. My first step would be to ask what rate you're programming at and try reducing.
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    OctoWS2811 random flashing colors

    You can use fastled with the audio library. :)
  18. C

    Trace Width for MK64FX512VMD12

    It all comes down to trace impedance, which in turn is based on a variety of factors including: Target board copper thickness (2 oz/ft is the 'standard', however 1 oz/ft is commonly available and cheaper, however will increase trace resistance) Board layer and layer stack-up. Is it a two layer...
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    Teensy 3.2 boot problem with 3.3V power (200 board statistic)

    We have observed a similar issue with a MC34063 DC-DC converter set for a 5V output on the PCB, fed into a 3.3V linear regulator. Fortunately our boards are powered individually, so usually takes just unplugging and replugging to bring them back to life. I too, could not find an issue with rise...
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    Datatype selection

    I'd echo tonton's suggestion above - I got into the habit of using explicit datatypes as he's described above some time ago, and long gone are my days of worrying about cross-platform compatibility and/or forgetting what size different data types are on different platforms. To get some accurate...
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    OctoWS2811 random flashing colors

    Gonna need some more information about what you're trying to do. Can you post a sketch? Hardware setup - pin connections, etc?
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    Audio Play Sd Wav, Sd_t3 issues

    Any ideas on this one anyone? Is there a way of re-initialising all of the Audio library objects perhaps? Current workaround is just to soft reset the teensy, but it's a far from ideal solution.
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    Audio Play Sd Wav, Sd_t3 issues

    Hi all, I've been banging my head against a wall on and off for weeks on this one. I have some Teensy 3.2's playing sound with the AudioPlaySdWav objects; two of them, fed into a mixer, fed to a DAC, using the normal SD card library. Shimples. Except, occasionally, at random intervals (could...
  24. C

    New project code named: teensquitto

    I think having an init call would make most sense. It's going to be very frustrating for a user who doesn't understand this functionality, if their application code on their teensy is constantly resetting because their ESP has a power issue or something! :)
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    I want to give PJRC my money, not faceless corporations!

    Hobbytronics are a UK retailer that supply the entire range :) See
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    New project code named: teensquitto

    This is very powerful - remarkably transparent. An excellent way of easily adding MQTT to teensy! Congratulations :) Forgive me if I've skipped past it somewhere, but do you have this up on GitHub or similar anywhere?
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    Any Plans for a Teensy Board with Bottom Pads on Top?

    Without wishing to make too strong a case, I thought I might just describe my usage of the Teensy 3.2 in a product. We required access to more GPIO than what was accessible via the through hole pins headers, and didn't have the space on the PCB to cater for the 'long' form factor used on the...
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    [posted] Teensy has joined the space program

    That's really interesting! Thanks for sharing!
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    [posted] Teensy has joined the space program

    That's awesome! Ishkabbible; do you mind me asking who you work for and how you got into working with OSIRIS-REx? Dream job stuff right there!
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    Teensy Programming without Windows Drivers

    Perfect. I figured that was the case. I'll give this a shot.
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    Teensy Programming without Windows Drivers

    Hi all, perhaps the topic name wasn't the best. Currently we are using TyQt to program a number of teensy's on a computer with the arduino environment. Problem being that windows seems to spend ages installing drivers for each new teensy that is connected, so takes a while before TyQt can pick...
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    Best way to get aa teensy (3.2) in a low height enclosure?

    Could you just use an enclosure with a lid, mount the board in the bottom of the box and remove lid for access? What sort of enclosure did you have in mind?
  33. C

    Disable Uart TX to use as GPIO

    Something I've been working on uses a multidrop serial connection, so each device needs to set it's UART TX pin to high impedance when it's not transmitting to avoid bus contention. I just do this by calling pinMode right after Serial.begin, on T3.2. Serial2.begin(57600); pinMode(10, INPUT)...
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    Voltage droop - Teensy LC

    I'd say Frank is spot on. You could start by only illuminating the LEDs to a lower level (eg, 127 instead of 255 for full brightness). In combination with a bulk cap of a few hundred uF, that might rectify the issue somewhat, although the state of your battery will affect the reliability.
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    Defective Teensy 3.2's ?

    From previous discussion, I believe PJRC load up the blink sketches by hand as the last step of manufacturing (and of course, in doing so, they test it). Possibly some mixed in returns or similar... You say "Hooking them up through a USB tester, I can see that there is 0 voltage running through...
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    Voltage droop - Teensy LC

    Hey, Could you provide us with a drawing or schematic of your setup?
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    ILI9341_t3(n) and snooze, power consumption in hibernate

    Sorry, I still appear to be missing something here. Why would disabling the CLK pin reduce current draw from 35mA to 0.3mA?
  38. C

    ILI9341_t3(n) and snooze, power consumption in hibernate

    Just to confirm as I have a similar setup using snooze and ILI9341 but hadn't actually verified the power consumption yet... Are we suggesting that leaving the SPI CLK pin high is preventing the teensy from hibernating? If so, why would that be?
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    Hardware Serial Flush

    /=====Update=====/ Now Resolved. As per usual, the issue was in my application code, where an occasional corrupted serial byte could cause the application to access memory beyond the size of an array. Remember kids, sanitise your input. Hi All, I'm currently debugging a Teensy 3.2...
  40. C

    triggering audio files with button from SD card

    This. Your current code executes several delays of 5000ms each loop, regardless of the result of the if statement.
  41. C

    Audio Library T3.2 Frequency

    Audio Library T3.2 CPU Frequency Hi All, I could certainly ascertain this experimentally but figured I'd ask here in case anyone knows the answer off the top of their head. What CPU speeds are supported by the Audio Library? Looking to keep power consumption of a device down where possible...
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    Request Teensy LC with More Memory

    Obviously I don't speak for Paul or PJRC, but there's often a lot of requests for variants of these products. I believe some tough calls had to be made when the LC was put together to keep the cost as low as possible whilst still retaining performance. The issue being that the LC needed to fit...
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    How interface 74ls245 with 74ls373

    Hi, this is a forum for PJRC products, which to the best of my knowledge doesn't include any kit with 8085. However, it is a good source of knowledge so someone MAY be able to help you. In order to do so, however, they're going to need a lot more information. What you're trying to achieve, your...
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    If you're just doing USB serial, CRC shouldn't really be necessary because it's all packaged up in the USB protocol anyways? :)
  45. C

    SPI with simulated chip select

    If you're worried about it, you could use a pull down resistor on the CLK inputs. This would keep them pulled down to GND unless pulled high by the buffers.
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    SPI with simulated chip select

    So, one option could be to use an SN74AHCT126, which is a 4-buffer package with output enable pins. You'd tie your clock pins to the input of each of the buffers, with the outputs going to the SPI devices. The use the enable pins as chip select pins. Buffers with a low logic OE will be tristate...
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    Good MCU-MCU Protocol to use?

    What sort of distances are you communicating over? You mentioned the amount of data in each loop, but how often are you expecting this data to be transmitted? (what's you actual average expected data-rate?)
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    Disassembly / Other IDEs

    Hi Michael; Yes it's these types of instructions that I intended to talk about; I did assume that it would generally pick those up automatically so thanks for that. I'll give it a shot and see what comes of it.
  49. C

    Disassembly / Other IDEs

    Great, thanks for the help all. It sounds like objdump will probably do what I have in mind. This project isn't intended as an in-depth analysis of GCC or optimisation; rather, as part of an overall Audio processing project, I hope to demonstrate how performance on different processor...
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    Disassembly / Other IDEs

    I'm hoping that I may be able to view the type of disassembly where it breaks down the higher level instruction lines and shows how they were implemented. Is that the -S configuration you're referring to.