Multi-SPI devices on same bus, different CS of course - HELP

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Re: Multi-SPI devices on same bus, different CS of course -

By Ecoli-557
- Wed Aug 31, 2016 8:48 am #54175 OK guys, it has been confirmed by testing and experimentation. I should have known this sooner, I know better than that...... The capacitance of the breadboard is significant at the higher frequencies - duh!
My solution instead of wasting time and money on prototype boards is to re-work the NodeMCU such that the male pins which normally are on the bottom of the module are now on the top (photo below).
ANY SPI-based device must also have their SPI bus pins up in the air and connected by soldered wires for the signals.
By doing this, you can have multiple devices on the same bus on your breadboard and continue to experiment away.

I still have problems with the basic interpreter but that maybe more my fault - although I have asked Mike to look into SPI transactions which can help enormously for those of us who are learning his Basic.
This is done by compiling in Arduino and taking advantage of sumotoy's libs, but it does not have all the niceties that Mike has added <grin>.

Hope this helps others......
Regards to All.
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Re: Multi-SPI devices on same bus, different CS of course -

By forlotto
- Wed Aug 31, 2016 11:19 pm #54215 Interesting, I am curious if you meant to say resistance is higher or if you actually mean capacitance is higher if so please explain what lead you to believe this. Normally any time the connection is smaller or weaker you introduce resistance not sure about capacitance and your use of it not exactly and electronics engineer either though ...

Hrmmm one would think then that by eliminating the bread board and just using dupont jumper wire and solder you could achieve the same effect.

I personally build harnesses for all my stuff rather than bread board I've used protoboard dunno never really had good experience with bread board so I either solder or wire. Certain things like 16p dip sockets I push into the bread board and it just pops right out maybe its just the cheap versions of breadboard I bought or my sockets anyways back to the issue at hand just a personal thing others have much success where I fail so don't let this discourage you get out your bread board and get that electronic motor running!

Thank you very much for sharing I will continue to watch and see for any developments I like what you did with your nodemcu though looks like a pretty good rework job.

I am holding out to see what kind of things you can find with the LCD good work though once again I liked this one and I also like the power plug modification which I still need to look at a little more in depth as time provides.

Take care and thanks for all that you share glad to have you aboard the espbasic forums we have a pretty good group of folks here glad you could join in keep the posts coming very enlightening.
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