Chip Choice for datalogging board

Projects General Guidance
1

I am making a custom datalogging board currently, and I'm wondering what you guys would choose as the chip you would use for the microcontroller?

I am considering a ATMEGA328P, or a ATMEGA4809 so far, but open to anything!

It's a Uno R3 footprint board, so nothing too oversized.

I also would really like it to have default support in the IDE so it's not too complicated for people who want to program it, or available through the boards manager.

It will have a micro SD card and RTC on the board, no WiFi at this point.

2

It all depends on the peripherals You didn't tell about.

3
  • This might be a good starting point.

serial_logger_pcb
serial_logger_pcb800×721 197 KB

1 Like
4

Per my original post:

and:

If it's a Uno R3 footprint, it has to have the same pinout as a Uno R3 so that all current shields are compatible.

5

Ok, that's awesome!

A massive amount of changes I'd do to that so it can be a drop in for a Uno R3, but definitely can use some of that circuitry!!!

6

schematic
schematic1657×1282 24.4 KB

IMG_3194
IMG_31941657×1282 12.5 KB

1 Like
7

Double posting?

8

No.

Please scroll to the top of the page and fully read my original post, it contains everything you said was missing.

10

Just looking at the chips you listed, the ATmega4809 uses roughly half the power at the certain clock speeds, as the ATmega328P.

The ATmega4809 using ~10mA @ 20MHz (1mA @ 2MHz).
The ATmega328P using ~13mA @ 20MHZ (2mA @2MHz).

11

Yes.

That's good for a datalogger, but don't forget a SD card absolutely saps power, so the board won't be awesome for battery powered projects...

12

If you are making a new product why not considering an arm cortex m0/m0+ ( 32 bit, super powerful, super periferals, available from different manufacturer, different memory sizes... forgot the price even lower )

2 Likes
13

If you do choose the ATmega4809, you can always change to AVR128DA48 later on.
They have an identical pinout, you will just need to get your board added into DxCore.

14

The 328P is obsolete use the 328PB instead, it also uses less power.
It you want something interesting consider the LGT8F328P

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15

You could check out the ATtiny3217(32KB of FLASH, 2KB of SRAM and 256B of EEPROM) or the ATtiny3227(32KB of FLASH, 3KB of SRAM and 256B of EEPROM).

They are more function packed then the ATmega328P or ATmega328PB and are cheaper then buying the new AVR family.

16

I quite like the 328PB, I've used it on a couple boards already

17

The one I made i added a 128 x 64 OLED display connector. The display sits above the other circuitry. I use a very light ASCII only display driver.
I also have an on board battery for the RTC.
I did not put the processor on the board but have a header so one can connect to whatever processor is needed.

2 Likes
18

I think @Railroader wants to know what kind if signals you want to log...
And whether you plan to have a display or control buttons or a cable to get the data off the logger...

19

Ah, ok. I'm going to be logging temperature, humidity, barometric pressure, wind speed, wind direction, rain rate, rain amount, UV levels, light levels, and lightning detection.

It might be nice to store it on a large storage device such as a micro SD card as I'll be getting the data off once a year. If I do that, I'll probably still want to get the data without removing the sd card so that measurements are not missed during that period of time. I may have a broken out control button, but that's not fully decided, mostly depends on how I decide to store the data.

No screen.

20

Analog inputs? Or SPI? Or something else?

21

Some analogue, some digital, SPI, and I2C. Basically a bit of everything