USB not working bacause of wrong resistors

Limited support for STM32F4 Discovery, Nucleo and custom F4 boards
Post Reply
BulbChangeExpert
Posts: 11
Joined: Mon Aug 21, 2017 2:49 am

USB not working bacause of wrong resistors

Post by BulbChangeExpert » Mon Aug 21, 2017 3:41 am

Not sure this was already spotted out but "repeating is good" they say.

With the STM32F407VET6 black board i had USB connection troubles, it wont be detected even if configured with BOOT-0 at 1 and BOOT-1 at 0... just "descriptor not responding" and stuff, i immediatelly tougth about an electrical\electronic problem.
Then i started to look at the USB circuit and bam!! Someone putted 22k (KILOOHMS) resistors instead of 22 ohms, already fixed, now the square black thingy has "next step problems" LOL.


Image


Image


Image

zmemw16
Posts: 1369
Joined: Wed Jul 08, 2015 2:09 pm
Location: St Annes, Lancs,UK

Re: USB not working bacause of wrong resistors

Post by zmemw16 » Mon Aug 21, 2017 4:03 am

nice spot :D :D off to check mine, also ZE's & ZG's
stephen

KHODIDAS11
Posts: 6
Joined: Sun Aug 20, 2017 4:35 pm

Re: USB not working bacause of wrong resistors

Post by KHODIDAS11 » Mon Aug 21, 2017 5:13 am

Hi

It works for me, I have succefully done usb serial, and usb acts as a com port. used "SerialUSB.begin();" like serial commnads only.

User avatar
RogerClark
Posts: 6673
Joined: Mon Apr 27, 2015 10:36 am
Location: Melbourne, Australia
Contact:

Re: USB not working bacause of wrong resistors

Post by RogerClark » Mon Aug 21, 2017 5:29 am

Looking at by "Blue" STM32F4 board, it looks like they have fitted 10 ohms "100" in place of the normal 22 ohms. (R49 & R50)

And also the resistor next to them (R51) is "103", so I suspect, like the Blue Pill, that they have probably fitted a 10k USB pullup :-(

It seems to work OK, (at least I can upload via DFU), but I have not tried much else apart from Blink, so I don't know if the Blue F4 will re-enumerate correctly to USB Serial.

When I get time I'll double check the 10K resistor and see if it is indeed the pullup.

Lennyz1988
Posts: 20
Joined: Fri Jun 30, 2017 9:11 am

Re: USB not working bacause of wrong resistors

Post by Lennyz1988 » Mon Aug 21, 2017 7:37 am

I suspected something like this. I also could not get the usb port to work on my pc. I will try to replace the resistors in the afternoon.

http://www.stm32duino.com/viewtopic.php?f=39&t=2386

I must have missed it, but indeed on my board there is also the wrong value. 22k on R18 and R19 instead of 22.

(STM32_F4VE_SCHEMATIC.PDF)

Image

User avatar
RogerClark
Posts: 6673
Joined: Mon Apr 27, 2015 10:36 am
Location: Melbourne, Australia
Contact:

Re: USB not working bacause of wrong resistors

Post by RogerClark » Mon Aug 21, 2017 8:17 am

BTW.

I'm not sure if this has been updated in STM32GENERIC (probably has), but the normal windows drivers that are installed for the F1 bootloader uses libusb-win32 which is not compatible with the F4

AFIK you need to install the WinUSB driver for the STM USB DFU device, via Zadig.

Also a newer version of DFU is needed for the F4 , than for the F1

However I suspect my copy of STM32_GENERIC is out of date and daniel may already have updated all of those files

Lennyz1988
Posts: 20
Joined: Fri Jun 30, 2017 9:11 am

Re: USB not working bacause of wrong resistors

Post by Lennyz1988 » Mon Aug 21, 2017 12:02 pm

Great! After I changed the resistors I finally get the usb working. I also installed the WinUSB driver for the STM USB DFU device, via Zadig. Now I need to figure out how I can upload to the board using this method with Arduino IDE :D

BOOT0 = 1
BOOT1 = 0

Image

BOOT0=0
BOOT1=0

Image

If was like this before:

Image

ag123
Posts: 711
Joined: Thu Jul 21, 2016 4:24 pm

Re: USB not working bacause of wrong resistors

Post by ag123 » Mon Aug 21, 2017 12:15 pm

little wonder why i had lots of problems initially, i solved the problem by using much better *shielded* usb cables, somehow that works, i didn't really looked at the resistors :lol:

BulbChangeExpert
Posts: 11
Joined: Mon Aug 21, 2017 2:49 am

Re: USB not working bacause of wrong resistors

Post by BulbChangeExpert » Mon Aug 21, 2017 12:25 pm

WOW!! my first problem discovered in some HW\SW so far... my granpa would be so proud LOL :mrgreen: :mrgreen:

they must have used a wrong SMD resistor reel, i've read about (every) people beeing capable of connect it

User avatar
RogerClark
Posts: 6673
Joined: Mon Apr 27, 2015 10:36 am
Location: Melbourne, Australia
Contact:

Re: USB not working bacause of wrong resistors

Post by RogerClark » Mon Aug 21, 2017 9:23 pm

@Lennyz1988

I think @stevestrong has been trying to get the F4 to run its DFU bootloader by using some code I found on a STM forum.

However, from what I have read, it's not working at the moment :-(

Re: zadig
I have successfully installed WinUSB using the wdi-simple.exe in the drivers folder. All that needs to change is the "type=1" for the Maple bootloader to "type=0" for the F4

Post Reply

Who is online

Users browsing this forum: No registered users and 2 guests