Search found 1864 matches

by victor_pv
Wed Feb 21, 2018 5:13 am
Forum: Projects
Topic: BluepillF4 Rev A. Tests, issues, options.
Replies: 1
Views: 110

BluepillF4 Rev A. Tests, issues, options.

I am starting this thread to document the tests we 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. Ma...
by victor_pv
Tue Feb 20, 2018 5:04 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 769
Views: 15555

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: 769
Views: 15555

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: 769
Views: 15555

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: 289

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: 769
Views: 15555

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 ...
by victor_pv
Mon Feb 19, 2018 3:52 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 769
Views: 15555

Re: F405 & F411 versions of the BluePill

There still might be some changes, I just received the micro USB connectors from AliExpress today, and they don't match exactly the Molex 47642-0001 footprint: the rear "hook" pins are closer to the PCB edge by 1 mm :x However, it perfectly matches the one on the original Bluepill! I asked the vend...
by victor_pv
Mon Feb 19, 2018 1:59 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 769
Views: 15555

Re: F405 & F411 versions of the BluePill

Normally the datasheet for each MCU series shows the differences with other common ones. I.e, in the F722 datasheet, the changes for LQFP64 package are in page 17: F722 datasheet from what I have seen: F405: Assemble all components as listed, including the 2x2.2uF capacitors F103: Replace both 2.2uF...
by victor_pv
Mon Feb 19, 2018 5:32 am
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 769
Views: 15555

Re: F405 & F411 versions of the BluePill

I just finished reflowing 2 boards without MCU, RGB, Charger, and 2nd LDO. I found out I didn't have any ferrites because an order I placed a while back with some was wrong, so I had to use 0R in place of all ferrites. I also didn't have enought 10uF capacitors to reflow more than 2 boards for the s...
by victor_pv
Sat Feb 17, 2018 1:20 am
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 769
Views: 15555

Re: F405 & F411 versions of the BluePill

I got a nice box from Mouser today with all the components I was missing. Tomorrow I hope to cut the stencil, reflow a board with all top components except the MCU and check it all up for shorts or anything like that, then solder the MCU. Other than the track we need to cut and watching out for shor...