Search found 43 matches

by mathieu
Sun Jul 26, 2020 5:37 pm
Forum: General Discussion and Questions
Topic: Best safe practices?
Replies: 3
Views: 251

Best safe practices?

I have a pyboard-D powered by the 5V output of this step-down voltage regulator and connected to an audio amp, an MPU, and a thread of 144 WS2812 leds potentially drawing several Amperes of current. The pyboard reads data from the MPU and generates sound and light effects in real-time. For debugging...
by mathieu
Sun Jul 12, 2020 10:04 am
Forum: Pyboard D-series
Topic: PYBD WBUS connector
Replies: 22
Views: 3249

Re: PYBD WBUS connector

chuckbook wrote:
Sun Jun 28, 2020 2:32 pm
When using small mezzanine connectors it is good practice to route unused pins to dummy tracks with vias close to the unused pads.
That sounds interesting, but could you explain why? Does this improve mechanical robustness? How?
by mathieu
Sat Dec 28, 2019 10:48 am
Forum: General Discussion and Questions
Topic: Surface mount soldering: can anyone help with two chips?
Replies: 10
Views: 1006

Re: Surface mount soldering: can anyone help with two chips?

What coworkers and I did a few times is just to solder all pads without taking care of possible interconnections between adjacent pads. And then to remove the excessive solder with solder wick. Sounds strange, but worked. I second this suggestion, which in my experience works very well. I've done s...
by mathieu
Fri Nov 08, 2019 4:28 pm
Forum: Programs, Libraries and Tools
Topic: Can anybody compile unix port with ulab on a Mac?
Replies: 1
Views: 506

Can anybody compile unix port with ulab on a Mac?

I successfully compiled micropython with ulab for the pyboard-D (SF6), but I can't seem to do the same for the unix port. This is on a Mac with macOS 10.13.6 with the latest XCode tools. Here is my build script: git clone https://github.com/micropython/micropython.git git clone https://github.com/v9...
by mathieu
Mon Nov 04, 2019 9:17 pm
Forum: Development of MicroPython
Topic: ulab, or what you will - numpy on bare metal
Replies: 106
Views: 12898

Re: ulab, or what you will - numpy on bare metal

In any case, if you can compile a working piece of firmware with the latest source as @jimmo suggested, would you mind reporting back here? If it is still not working, then I would be interested in finding out where the problem lies. I did compile a working version based on micropython 1.11 (6f75c4...
by mathieu
Sun Nov 03, 2019 3:02 pm
Forum: Development of MicroPython
Topic: ulab, or what you will - numpy on bare metal
Replies: 106
Views: 12898

Re: ulab, or what you will - numpy on bare metal

I would suggest changing all occurrences of "float" to "mp_float_t", that will allow it to compile for all targets with the FP precision supported/configured by the target. Done. I have also uploaded compiled firmware for pybv11, and pybd_sf6 to https://github.com/v923z/micropython-ulab/releases. I...
by mathieu
Fri Nov 01, 2019 3:00 pm
Forum: Development of MicroPython
Topic: ulab, or what you will - numpy on bare metal
Replies: 106
Views: 12898

Re: ulab, or what you will - numpy on bare metal

Done. I have also uploaded compiled firmware for pybv11, and pybd_sf6 to https://github.com/v923z/micropython-ulab/releases. Thanks again! I just tried on pybd_sf6 and everything seems to work fine, except that: - By default I can connect to the board using rshell. - But after I modify boot.py to i...
by mathieu
Fri Nov 01, 2019 1:06 pm
Forum: Pyboard D-series
Topic: Possible issue with WS2812 driver on pyboard-D
Replies: 4
Views: 914

Re: Possible issue with WS2812 driver on pyboard-D

It would be good to know if the fix is down to the baudrate change or separating initialisation from instantiation. Just checked and the single-line declaration also works. This must be linked to the approximate baudrate (see http://docs.micropython.org/en/v1.9.3/pyboard/library/pyb.SPI.html ). Ano...
by mathieu
Thu Oct 31, 2019 10:21 pm
Forum: Development of MicroPython
Topic: ulab, or what you will - numpy on bare metal
Replies: 106
Views: 12898

Re: ulab, or what you will - numpy on bare metal

I am trying to compile ulab for the PYBD_SF6 on macOS following instructions found at https://github.com/v923z/micropython-ulab/blob/master/docs/source/ulab.rst . When I run make BOARD=PYBD_SF6 CROSS_COMPILE=/usr/local/bin/arm-none-eabi- I get the following error: make: *** No rule to make target `l...
by mathieu
Thu Oct 31, 2019 10:11 pm
Forum: Pyboard D-series
Topic: Possible issue with WS2812 driver on pyboard-D
Replies: 4
Views: 914

Re: Possible issue with WS2812 driver on pyboard-D

Replying to my own thread: I was able to fix the issue by replacing, in the ws2812 module,

Code: Select all

self.spi = pyb.SPI(spi_bus, pyb.SPI.MASTER, baudrate=3200000, polarity=0, phase=0)
by

Code: Select all

self.spi = pyb.SPI(spi_bus)
self.spi.init(pyb.SPI.MASTER, baudrate=6400000, polarity=0, phase=0)