I wanted to use Pins, can someone sent me help per dm
This is not practical; rather, you connect both NodeMCU and UNO with the PC using two UB Ports and then connect the boards for data communication. (Practically, the IO lines of NodeMCU are 5V tolerant; so, there will be no need of logic shifters.)
Only the RX pin actually is on most nodeMCU's . True that in a practical sense that means you can connect TX to RX & RX to TX, but only on the primary pair of the nodeMCU not the pair that becomes active after Serial.swap() And do not think any of the other GPIO pins on the nodeMCU are 5v tolerant. They are not !
I don't think that is even possible. There is no 5v pin on the nodwMCU, just 3.3v & Vin. Vin is what it claims, a voltage input.
Don't know what you need to power that with. The link refers to a shield, but no pin configuration, just jumper settings.
Don't know, if the shield requires 5v, it will be tricky, but what does the shield do ? what do the sensors return ?
And you are referring to those as such ? D0 & D8, not 0 & 8 !
But the SPI pins on a nodeMCU are not the same as on an UNO.
check here so you will need to change that as well. The shield will obviously not match the pinout of the nodeMCU.
I think the sensors will probably work on 3.3v
Does it work now ? I normally use the other SPI (I think ..? i don't use SPI a lot...)
No it's interesting enough, but i have to ask you if it's working now, you could have told me that straight away.
Anyway, looking at the schematic it appears that there are parts running at 5v like ADP7102ARDZ, but that appears to be a voltage regulator powering the whole thing at 3.3v But there is also IOREF which is connected the TXB0108PWR which is connected to the SPI pins of the shield. It was a bit of a search through the layout files but then i found it. Now i suspect that IOREF provides a reference voltage (5v) for the SPI pins if it would be connected to an UNO , while U5 is actually powered with 3.3v.
So basically all we have is 3.3v , and the IOREF pin should be connected to it.
We don't have 5v, and in the datasheet of the ADP7102 it states:
VIN = (VOUT + 1 V) or 3.3 V (whichever is greater)
That would mean we are 1 volt short with our 3.3v, but i guess we could just bypass the regulator, i mean remove it and connect pins 1 & 8 on the IC should do the trick. I don't know what happens if you connect 3.3v to the point (hole/via) marked that, i mean i am not sure what that does to the regulator, but it should power the shield properly, as long as the regulator does not disturb that. The datasheet states :
VOUT to GND −0.3 V to +20 V
as a maximum rating, so it should be ok.
The regulator is rated for 300mA so i am confident that the nodeMCU should be able to power it all.
Which means what exactly, that the sensors are not providing data ?
So we are getting rid of the UNO.
Glad to hear it!
Hey Paul can you check my reasoning, should the regulator on the shield be removed or just connect 3.3v to the via/hole ?
I'm afraid I can't say - I did not look at or find the schematic and full details to that ADC module.
Does it use the 3.3 V in any way as a voltage reference?
All components are powered with 3.3v except for the 3.3v regulator that is powering them. that takes Vout + 1v and is normally connected to 5v. The SPI port is powered with 3.3v for VccA and connected to IOREF for VccB
I thought i included all links.
I am not doubting you!
I thought of a 3rd option and it's a pretty good one. Create a 5v output on the nodeMCU ! Tap on at the pin of the regulator. That is actually the best source for the 5v input for the shield. IOREF should still be connected to 3.3v
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