Docmentation of Solder Bridges

[Andrew Neil]

There have been several threads lately where the posters have seemed completely unaware of what a "solder bridge" is, and how to use it.

Example:

https://community.st.com/t5/stm32-mcus-products/uart-in-stm32-l432kc/m-p/689335/highlight/true#M253126

Perhaps this is something that needs to be explicitly explained & illustrated?

[BarryWhit]

How can you build a bridge out of solder?!? don't be silly. Not enough tensile strength. :thinking_face:

[waclawek.jan]

> Perhaps this is something that needs to be explicitly explained & illustrated?

I don't think so.

I'm afraid the users you're referring to did not take the pain to open the respective manual and read it. What are the chances they would read yet another document?

JW

[Andrew Neil]

Not a separate document - it should be in the same document.

But, if they haven't even opened that document ...

[Andrew Neil]

Another today:

https://community.st.com/t5/stm32-mcus-boards-and-hardware/program-not-running-when-powering-from-external-source/m-p/724001/highlight/true#M21559

[Andrew Neil]

Another one today:

https://community.st.com/t5/stm32-mcus-boards-and-hardware/stm32l552-nucleo-board-hse-error/m-p/729990/highlight/true#M21883

As these processors get more and more complex, it becomes more likely that they will be programmed by "pure software" people - who are less likely to be familiar with these hardware details.

[Andrew Neil]

Another today:

https://community.st.com/t5/stm32-mcus-products/to-determine-the-component-of-quot-sb1-quot-in-stm32f407g-disc1/td-p/736738

[waclawek.jan]

We could perhaps concoct some FAQ. Several related Q come into mind, such as

- where's the documentation

- where's the schematics

- where is example code

- where is the original binary which came preprogrammed

- why some pins don't work (because they are connected to on-board resources).

together with some historical-contextual remarks.

JW

[Andrew Neil]

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@waclawek.jan wrote:

We could perhaps concoct some FAQ.

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aka "Knowledge base" articles?

eg, "Solder Bridges: What They Are and How To Use Them"

I made a start here (focussing on the "what"):

https://community.st.com/t5/stm32-mcus-products/to-determine-the-component-of-quot-sb1-quot-in-stm32f407g-disc1/m-p/736824/highlight/true#M264800 

[waclawek.jan]

Nice, but I'm not sure newcomers these days have the attention span to follow that. And that's a single A to a single Q... I was thinking about a "I've bought a devboard now what" or even "I want to buy a devboard, any recommendations?" one.

> In some cases, rather than just use a "blob" of solder, a zero-ohm resistor (aka "zero-ohm link") will be fitted:

I wouldn't say "in some cases". It's actually hard to mass-manufacture a solder blob, so IMO all ST boards have 0Ohm resistors (often unmarked) on the factory-closed SBs; but it's okay to use solder blob when the user wants to close them (in other words, users don't need to be intimidated by the 0Ohm resistors, they are OK but not necessary).

JW