Search found 1868 matches

by victor_pv
Sat Feb 24, 2018 4:51 am
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 773
Views: 15884

Re: F405 & F411 versions of the BluePill

I got sdio working fine in 4bit mode at 24Mhz with an F1. I need to check the erratas but if I remember right there was an errata that limited the max speed. If not, I'll try to bump it to 36Mhz. Also need to test comparing the data read and written to make sure there are not bit errors, but given t...
by victor_pv
Fri Feb 23, 2018 11:57 pm
Forum: OSX
Topic: Can upload with bootloader but no COM ports afterwards
Replies: 5
Views: 42

Re: Can upload with bootloader but no COM ports afterwards

What board are you using, and what board did you select in the IDE? Different boards have different circuits to cause a re-enumeration for the host, and the code needs to control that. Most generic boards (i.e. bluepill) do not have any circuit for that, and we use a trick with the MCU pins to do it...
by victor_pv
Fri Feb 23, 2018 5:04 am
Forum: New users MUST post here first, and let us know a bit about you and your projects
Topic: chrissv: Playing with "Blue Pill"
Replies: 10
Views: 101

Re: chrissv: Playing with "Blue Pill"

I believe he is asking how to use the SerialUSB when uploading with the serial bootloader. I don't remember for sure, but I think you will need to declare a SerialUSB in your code, and start the port with .begin() Call it anything you want other than Serial or Serial1...N because those are taken for...
by victor_pv
Fri Feb 23, 2018 3:58 am
Forum: Projects
Topic: BluepillF4 Rev A. Tests, issues, options.
Replies: 2
Views: 168

Re: BluepillF4 Rev A. Tests, issues, options.

F1 libmaple core, SDIO 1bit mode with 103RCT MCU. I still have random problems, but could be in the code and not the board. It could also be that the capacitor for the board needs to be larger, and I need to receive ferrite beads or inductors, currently using a 0R to power the SD connector, so there...
by victor_pv
Wed Feb 21, 2018 5:13 am
Forum: Projects
Topic: BluepillF4 Rev A. Tests, issues, options.
Replies: 2
Views: 168

BluepillF4 Rev A. Tests, issues, options.

I am starting this thread to document the tests we are completing with the board, the issues we find and possible solutions, and the configuration options in the boards. Let's keep this thread short and only with facts, and keep all discussions around the designs etc in the main thread for the board...
by victor_pv
Tue Feb 20, 2018 5:04 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 773
Views: 15884

Re: F405 & F411 versions of the BluePill

I found this post in which it's mentioned that was not possible to route AGND to the headers: http://www.stm32duino.com/viewtopic.php?f=19&t=2633&p=37893&hilit=ferrite#p37893 I think in that case it's safe to just replace the AGND FB with a 0R or a solder bridge, and may even help to keep noise unde...
by victor_pv
Tue Feb 20, 2018 4:15 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 773
Views: 15884

Re: F405 & F411 versions of the BluePill

racemaniac wrote:
Tue Feb 20, 2018 4:01 pm
I can't check right now, but isn't one of the grounds exposed the agnd? (i thought it was one of the compromises towards backwards compatibility we made)
Nothing is labelled as AGND in the board, but I can't check the schematic to confirm right now.
by victor_pv
Tue Feb 20, 2018 3:55 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 773
Views: 15884

Re: F405 & F411 versions of the BluePill

I started with the F103 for 2 reasons: -The F103 has mature core with plenty of libraries, sketches etc, and I know how everything works better than the F4. -The MCU is half the price, so if I burn 1 it won't hurt as much. So far I tested the button with a 2k resistor, and works just fine. I believe...
by victor_pv
Mon Feb 19, 2018 11:13 pm
Forum: Custom design boards
Topic: STM32-UNO(ARMDuino)
Replies: 10
Views: 305

Re: STM32-UNO(ARMDuino)

Nice work. R6 is definitely wrong. Rather than a pull down it should be a pull up, and the correct resistor value is 1k5. Otherwise it may work on some computers and fail on others. I just replaced the wrong resistors in a couple of bluepills after then would randomly fail half way during sketch upl...
by victor_pv
Mon Feb 19, 2018 5:33 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 773
Views: 15884

Re: F405 & F411 versions of the BluePill

I updated the list. Thinking about the user button, I have a concern on R5 being 0R. If it's populated and an unaware user connects PB8 to GND for whatever reason in his circuit, or drives PB8 down for some use, and then press the button, it can cause a short. Imagine a case where he chooses to use ...