Search found 110 matches

by chuckbook
Thu Jan 16, 2020 11:57 am
Forum: Pyboard D-series
Topic: Pyboard D RTC accuracy
Replies: 5
Views: 126

Re: Pyboard D RTC accuracy

This sounds too good to be true. Doesn't the DS3231 datasheet claim +/-2 ppm which (roughly) means +/-1 min/a?
Anyhow, this is still a very good result.
by chuckbook
Mon Dec 30, 2019 8:06 pm
Forum: MicroPython pyboard
Topic: pyb.ADCAll() side effect
Replies: 13
Views: 2111

Re: pyb.ADCAll() side effect

1. Note that core_vbat refers to the RTC backup battery. To read supply voltage use vref.
2. core_temp is stored in cor_dat[3]!
3. On a PYBD will never be bigger than 3.3V (well +/- some error) due to the LDO used for Vdd.
by chuckbook
Sun Dec 15, 2019 5:25 pm
Forum: General Discussion and Questions
Topic: Changing LED colour on USR button press
Replies: 3
Views: 163

Re: Changing LED colour on USR button press

try this: import pyb sw = pyb.Switch() leds = [pyb.LED(1), pyb.LED(2), pyb.LED(3)] led_state = 0 def cycle(): global led_state print(led_state) led_state = (led_state % 3) if led_state == 0: led_state = 1 leds[0].on() leds[1].off() leds[2].off() elif led_state == 1: led_state = 2 leds[0].off() leds[...
by chuckbook
Tue Oct 22, 2019 9:44 am
Forum: Pyboard D-series
Topic: WBUS-DIP28 reset pin does not reset the Pyboard
Replies: 5
Views: 612

Re: WBUS-DIP28 Please could someone try this

NRST isn't connected to WBUS-DIP28 by design (and the route should not be in the schema). It might be a bit inconvenient but DIP28 NRST can be connected to PYBD NRST by a bodge wire or, and this made more sense to the designer, handle DIP28 NRST through another GPIO. With NRST being hard wired betwe...
by chuckbook
Tue Oct 22, 2019 9:05 am
Forum: Pyboard D-series
Topic: Gerber files for d series?
Replies: 5
Views: 497

Re: Gerber files for d series?

The PYBD was designed to allow a regular DIP-16-600 footprint if only X-SKIN is used. Y-SKIN ports are also placed to form a regular DIP-16-600 footprint but interleaved and rotated by 180 deg to the X-SKIN ports. Note that pins 16, 15 and 13 are different for the X and Y SKIN footprints. This allow...
by chuckbook
Thu Oct 10, 2019 9:23 am
Forum: MicroPython pyboard
Topic: THE FINAL SOLUTION: TRUE RTC ON PYBOARD
Replies: 2
Views: 415

Re: THE FINAL SOLUTION: TRUE RTC ON PYBOARD

RTC backup battery works pretty well on PYBV11 but there are some caveats: RTC driver inside MPY has a multi level fallback strategy to handle various hardware options and even HW faults if 32kHz crystal isn't installed, broken or shows a power-up delay above a certain limit, RTC clock uses LSI osci...
by chuckbook
Fri Oct 04, 2019 9:18 am
Forum: Development of MicroPython
Topic: ulab, or what you will - numpy on bare metal
Replies: 62
Views: 4252

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

Don't get confused about the absolute size of the code. There are a lot of additional features included. I just wanted to demonstrate code size increase for -Os and -O2.
by chuckbook
Thu Oct 03, 2019 5:15 pm
Forum: Pyboard D-series
Topic: I may have bricked I2C(2)
Replies: 13
Views: 886

Re: I may have bricked I2C(2)

If Y9 can't be used as GPIO in input and output mode there is no way it can operate in I2C mode.
As it is pretty hard to kill a GPIO port with voltages of 0V..+5V there might be a change that there is a shortcut somewhere that affects Y9.
by chuckbook
Thu Oct 03, 2019 5:03 pm
Forum: Development of MicroPython
Topic: ulab, or what you will - numpy on bare metal
Replies: 62
Views: 4252

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

Here are the code sizes of -O2 and -Os build options.

Code: Select all

   text    data     bss     dec     hex filename
 463704      40   28052  491796   78114 build-PYBV11_O2/firmware.elf
 424484      40   28052  452576   6e7e0 build-PYBV11/firmware.elf
by chuckbook
Thu Oct 03, 2019 3:32 pm
Forum: Pyboard D-series
Topic: I may have bricked I2C(2)
Replies: 13
Views: 886

Re: I may have bricked I2C(2)

This is exactly the reason why Y9 & Y10 don't have internal pull-ups. If PYBD is integrated in another design it is usually required to put I2C pull-up resistors on the supporting board (or even on a remote board). Using 5V as pull-up source is ok. Pull-up resistor values should be in the range of 1...