switching from Uno to nano

Projects General Guidance
1

Hey all,
I'm an arduino newb, but a DIY vet. Long story short I'm working on starting a business to help support myself and my Mother. I'd like to start making up some Temp and RH data loggers to sell, since having this information in an indoor garden (or lots of other situations) can be invaluable in a lot of cases, but many growers don't have finances to go buy a pre-built logger, I'm hoping people get as excited about this as I was when I first saw it working. Here's my question:

Would there be any real downside to swapping out the UNO for a Micro or Nano?

I built my data logger with an Uno R3 (a clone I think, Elegoo) and it worked fine. I started with the uno bc it seemed to be the most popular. Now that I've worked with the board and learned more about the other boards, and seeing that they're much more similar than I thought, I'm considering using a different board for the model I sell.

I figured that if the Nano/Micro were cheaper, yet can do the job as well as the uno, it's a no brainer!

2

A Nano is just a stripped-down Uno so no problem, but it may be a half-baked approach, in that they are still development devices. If you are serious about some sort of mass production, you might look at using the guts of the Uno on a custom PCB, or maybe a similar MCU in a simpler package.

3

I figured that if the Nano/Micro were cheaper, yet can do the job as well as the uno, it's a no brainer!

The Micro uses another processor (ATmega32U4) than the UNO/Nano, so you might need to change code if you move to that board.

4

My personal projects always start on an Uno and then move to a Nano. The Uno is easier to handle and has pins to use with jumper wires to a breadboard. When all is working I move to a Nano with no pins and use small wires soldered into the proper holes to make the permanent connections.

We also make a commercial product that uses the Nano and soldered wires. Be sure to leave access to the USB connector so you can replace the program when bugs are discovered.

Paul

5

As above if you want to make some sort of product, I'd seriously think about having a custom pcb made, with the required components of the nano, and whatever other components you need. It would be a lot more reliable in the long run for day to day use.

To answer your question, there's no real downside, except less pins. But if you dont need them, it doesn't matter does it :confused: lol

6

What other hardware are you using for your data logger? Are you currently using any shields or breakout boards?

7

SaintSkinny:
I'd like to start making up some Temp and RH data loggers to sell, since having this information in an indoor garden (or lots of other situations) can be invaluable in a lot of cases, but many growers don't have finances to go buy a pre-built logger,

I find that rather difficult to believe. I severely doubt you could even construct one for $20 (US), let alone cheaper!

SaintSkinny:
Would there be any real downside to swapping out the UNO for a Micro or Nano?

Virtually none.

SaintSkinny:
I built my data logger with an UNO R3 (a clone I think, Elegoo) and it worked fine. I started with the UNO bc it seemed to be the most popular. Now that I've worked with the board and learned more about the other boards, and seeing that they're much more similar than I thought, I'm considering using a different board for the model I sell.

I figured that if the Nano/Micro were cheaper, yet can do the job as well as the UNO, it's a no brainer!

Well, I suppose the UNO is more heavily marketed by the Arduino project, but really it is only for experimental or demonstration use, except perhaps where a particular shield allows it to perform the whole of your application. For actual "real world" applications, the Nano is the most appropriate.

Nick_Pyner:
A Nano is just a stripped-down UNO so no problem, but it may be a half-baked approach, in that they are still development devices.

What a curious suggestion! :astonished:

In what respect is it "stripped-down"? The only difference is the use of a dedicated-purpose USB bridge rather than the 16U2 in the UNO, but it is rare indeed for anyone to actually utilise the secondary processor. A Nano is electrically almost identical to a Duemilanove.

Nick_Pyner:
If you are serious about some sort of mass production, you might look at using the guts of the UNO on a custom PCB, or maybe a similar MCU in a simpler package.

It would have to be mass production - in the thousands - to justify the cost of inventory to customise the Nano itself. Far more practical to use Nanos (albeit "clones") as daughterboards to your custom PCB, generally cheaper and easier assembly.

Paul_KD7HB:
Be sure to leave access to the USB connector so you can replace the program when bugs are discovered.

Well, if you did not want the USB function, you would be using a Pro Mini. In this particular case, it is the download portal - though removing a SD card is another approach.

wkdkris:
As above if you want to make some sort of product, I'd seriously think about having a custom PCB made, with the required components of the Nano, and whatever other components you need. It would be a lot more reliable in the long run for day to day use.

Just how do you imagine it would be more reliable? :roll_eyes:

wkdkris:
To answer your question, there's no real downside, except less pins. But if you don't need them, it doesn't matter does it

Less pins? Do you actually know what a Nano is? (Hint: The Pro Mini/ Nano has two extra, analog input only, pins compared to the UNO.)

8

Nick_Pyner:
If you are serious about some sort of mass production, you might look at using the guts of the Uno on a custom PCB, or maybe a similar MCU in a simpler package.

wkdkris:
As above if you want to make some sort of product, I'd seriously think about having a custom pcb made, with the required components of the nano, and whatever other components you need. It would be a lot more reliable in the long run for day to day use.

If all goes well, I was planning on switching to running it on a PCB. For now I'm thinking I'll just use the uno or nano and put the remaining components on a pcb.
What do you all think about these doohickeys?

drummin89:
What other hardware are you using for your data logger? Are you currently using any shields or breakout boards?

I'm using a DHT22 and a Micro SD module for my personal logger. The things I want to change are adding an RTC and a display.

When I build some to sell I was thinking about using this SD shield That has a built in RTC (I was originally looking at using seperate modules for RTC and SD until I found these)

Being a complete newb, I want to make sure I got the lingo correct. is breakout board basically another word for breadboard friendly Module?

another thing I want to ask about is shields, can you use more than one shield on a board? IE would I be able to stack an LCD shield on an SD shield on the Uno?

pylon:
The Micro uses another processor (ATmega32U4) than the UNO/Nano, so you might need to change code if you move to that board.

I was a bit confused on the names, my bad. I meant the Nano or Mini

9

lots of good comments in this thread
Since you are just starting out I would suggest moving to the Nano
it offers the USB and is almost identical to the Uno all the same procedures you were doing now Movinig a mini removes the USB so it makes it harder to program but it may save you pennies

When selling product and you're making more of it it would behoove you to actually make a custom PCB
Making your own circuit board gives you a lot of flexibility

10

SaintSkinny:
If all goes well, I was planning on switching to running it on a PCB.

Despite what you might have read above, that has to be a good idea, but you might be at cross purposes.

When I build some to sell I was thinking about using this SD shield That has a built in RTC (I was originally looking at using seperate modules for RTC and SD until I found these)

For the above reasons the separate modules on PCB would be the way to go. You can get an SD module for under a dollar. That shield has a DS1307 RTC and, while time stamping may not be that critical, I'm sure their poor accuracy makes them a seriously bad idea for anything you might want to put on the market, while a DS3231 module hardly costs anything more.

Being a complete newb, I want to make sure I got the lingo correct. is breakout board basically another word for breadboard friendly Module?

Yes, by virtue of having pins at 0.1"

another thing I want to ask about is shields, can you use more than one shield on a board? IE would I be able to stack an LCD shield on an SD shield on the Uno?

Yes, that is why they are made the way they are. Needless to say, there are practical limits, not the least being available power, but some shields get power from VIN, or even have their own power input

11

well.... the UNO has 32 pins on the platform, A4/A5 are doubled and found over on the opposite corner near D13
the NANO has 30 pins, and adds functionality by bringing out 2 additional analog lines from the MCU. increasing the analog to 8 pins.
the head to head is that the UNO has 2 more pins on the board
the NANO has 2 fewer pins, but 2 additional inputs.

If cost is a concern, then a mini without a USB would be the lower cost way to create a lower cost package.
I have used the mini and an RTC boar and an SD board on a project I had made years ago.
it was cheaper, easier and faster for me to use those boards than to try to buy the parts and put them on my own board.

if we were sitting around tossing ideas about the best way to move this project, I would offer that buying the micro, an SD card holder and an RTC and then putting them into an enclosure would be one way to take advantage if what is available and then to see if the market wanted more.
once you have sold a few, and people want more features, you can add functions. at some point, it makes economic sense to commit to a purpose build PCB, but that will come as a natural point in time.

12

dave-in-nj:
if we were sitting around tossing ideas about the best way to move this project, I would offer that buying the micro, an SD card holder and an RTC and then putting them into an enclosure would be one way to take advantage if what is available and then to see if the market wanted more.
once you have sold a few, and people want more features, you can add functions. at some point, it makes economic sense to commit to a purpose build PCB, but that will come as a natural point in time.

That's a great idea. I've gotta start somewhere, and I have a feeling some of my first customers will likely be some of my friends in the DGC. Talking to some of my grower buddys they seem to think garden automation is a better route to go.

13

I don't think you have explained whey they would want to purchase your data-logger for at least double the price of the one I cited in reply #6? :open_mouth:

14

Paul__B:
I don't think you have explained whey they would want to purchase your data-logger for at least double the price of the one I cited in reply #6? :open_mouth:

It'll have a screen for one. One of the biggest differences would be, assuming I can get it to work, is I'm trying to have my logger spit out the Vapor Pressure Deficit (VPD) along with the Temp and RH...but the Data logger is only the first step, I'll be doing environmental controllers and garden automation as well. I may put the option out to sell it as a diy kit, too.

The reason I was thinking about starting off with the data logger was financial. I'm a caregiver for my Mom (she had a couple battes with AML [a type of leukemia] and a Bone Marrow/Stem cell transplant)but don't get paid for it. Things have been really rough and I'm trying to start this business to take the burden off of her. After all she's been through, I just want her to be able to relax and not constantly stress about money.

I've been considering the possibility of having the controller actually log when it turns the appliance on and off, so when it's graphed it gives that little bit of extra insight.

15

any comment on these guys?

700×700 79.1 KB

Heres the link to the product page.
It'd be down the road a bit, just thought I'd get some opinions. Looks like a good way to program the chip before going to PCB on a small scale.