Recent content by MarkT

Ideally all the wires from mcu to motor driver should go through the same ferrite so it removes common-mode interference but doesn't add differential mode interference. Definitely add 10nF to 100nF on those limit switch inputs next to the mcu, change 10k to 2k2 as well perhaps.

If the system is starved of blocks odd things can happen if something is freeing blocks at all, don't take the fact it "works" with 11 to mean its properly working, for if it were 12 would definitely work too.

Connecting a motor direct to pin 8 of the Teensy? That doesn't sound safe, back EMF, burn out the pin through overcurrent, ESD through handling the motor - several ways this could be bad news.

Yes, its an unmodified Audio adapter D that I've had for a while but only just soldered headers too and started using. Since the QA403 has high input impedance the caps distortion should be relatively low. I hope they are C0G/NP0 type, because they need to be into a low impedance load as...

Yes I think 80kHz for the measurement bandwidth - which may be a little unfair. Well you could measure it directly by sending to USB and capturing the raw data without using any DAC for a definitive answer - the SGTL DAC is clearly dominating the difference between Hires and not.

AudioSynthWaveformSineHires seems to make a very small difference of 0.5dB or so:

Good point. Will retry later.

I took the Waveforms Audio example, set the frequencies to 1000Hz, wave type to sine, and maxed the levels with sgtl5000_1.lineInLevel(0); sgtl5000_1.lineOutLevel(13); And looked at the line outputs with my QA403 audio analyzer: Which is a bit shy of the -100dB THD and -85dB THD+N...

It probably sent part of the chip into CMOS latchup...

Yes, you are missing SYS_FS and MCLK_FREQ, also in CHIP_CLK_CTRL which sets the clock, this in combination with the RATE_MODE determines the sample rate, see datasheet table 18. I think you'll need to reduce the MCLK frequency sent to the chip to get the lowest sample rates though. But why not...

Well the schematic does not show the power supply arrangements or decoupling for one thing. Where does the +/-15V come from for instance? I do note the TL072 trying to drive 470nF through 16 ohms - likely to oscillate, opamps can't drive heavy capacitive loads without a fair bit of resistance...

The T4 is absolutely _not_ 5V tolerant, 3.3V is the limit for all pins - this is clearly stated in the data for the device. You require level converters to talk to a 5V chip (if you haven't fried the T4 already).

Recommend testing every USB cable you get whether it has data and if not marking it conspicuously...

Why would you need to use non-blocking WS2812 update? They update fast enough, you only have human input to respond to so interrupts won't be needed.

Or this: https://www.canford.co.uk/CANFORD-HSS-HELICAL-DOUBLE-SCREENED-SINGLE-CABLE