Hello everyone! 
For a project I'm having I need an AVR chip (probably from the ATmega family), which is fully Arduino-Competable and has more Flash and RAM than the popular ATmega328p, yet less Flash and RAM than the ATmega1284p.
In my project, I mainly use Ethernet and SD card functions so I don't need many pins, just more memory (the FAT16 and Ethernet library are RAM and Flash eaters), so the 328p doesn't have enough RAM and Flash. Yet, I find it a complete overkill to use the ATmega1284p, as I'll need around 40,000 bytes of flash, 4K bytes of RAM and only 4 I/O pins...
Is there any chip which comes between these two microcontrollers?
Thanks!
Dan
How's the price compare to split your task between two 328's, or add an ATtiny to the 328?
Geoff
idodaniel:
Hello everyone!
For a project I'm having I need an AVR chip (probably from the ATmega family), which is fully Arduino-Competable and has more Flash and RAM than the popular ATmega328p, yet less Flash and RAM than the ATmega1284p.
In my project, I mainly use Ethernet and SD card functions so I don't need many pins, just more memory (the FAT16 and Ethernet library are RAM and Flash eaters), so the 328p doesn't have enough RAM and Flash. Yet, I find it a complete overkill to use the ATmega1284p, as I'll need around 40,000 bytes of flash, 4K bytes of RAM and only 4 I/O pins...
Is there any chip which comes between these two microcontrollers?
Thanks!
Dan
Arduino Comparison
But, IMO, just use the Mega... there is always something else that gets crammed into a project and the headroom will be useful. Mega clones are under $10.
Ray
My Projects
strykeroz:
How's the price compare to split your task between two 328's, or add an ATtiny to the 328?
Geoff
I'm generally a proponent for multiple uC's in a new design. Multiple cheap uC's should be considered as part of the hardware architecture as the main program can often be simplified and made more robust in these ground-up designs.
Since the Op seems to have a completed program, s/he may be reluctant to invest the time to redesign ... Clone Mega2560 are available for under $10 USD.
Ray
My Projects
strykeroz:
How's the price compare to split your task between two 328's, or add an ATtiny to the 328?
Geoff
Well, I haven't think of it by now, yet it can be a little problematic - I get data from the Ethernet, stores it in an SD card and then checks the SD card for the data I saved in it every two minutes. Two uCs using the same SD card can cause a lot of issues, I think...
mrburnette:
I'm generally a proponent for multiple uC's in a new design. Multiple cheap uC's should be considered as part of the hardware architecture as the main program can often be simplified and made more robust in these ground-up designs.
Since the Op seems to have a completed program, s/he may be reluctant to invest the time to redesign ... Clone Mega2560 are available for under $10 USD.
Ray
My Projects
Hi!
Well, the prototype of the project is based on the Mega. Yet, I need to make it as a industry-end-level product, which means - I need to solder everything up to a PCB, making it completely standalone. I don't want to use any Arduino, only it's software and firmware, so buying a cheap Mega clone isn't really an option
How about an ATmega644p?
64kB flash, 4kB RAM, 2 UARTs and 32 IO pins. Compatible with Arduino IDE too
idodaniel:
Well, I haven't think of it by now, yet it can be a little problematic - I get data from the Ethernet, stores it in an SD card and then checks the SD card for the data I saved in it every two minutes. Two uCs using the same SD card can cause a lot of issues, I think...
I'm sure that could be a problem. However, you could break the task such that one uC does the network comms and SD reading, the other requests data from that one as required and does whatever the next step is. I'm not sure you'll gain much aside from complexity over just sticking with the larger single uC in this case you're describing though.
Geoff
hansibull:
How about an ATmega644p?
64kB flash, 4kB RAM, 2 UARTs and 32 IO pins. Compatible with Arduino IDE too
Yeah, I think that'll be my uC
Do you know if the 644 support the SD library and the Ethernet library? Those are the main ones I'm using..
Thanks!
Yes, it does. Check out the MightyCore for adding support for the ATmega644p. It contains a working SD and Ethernet library too