Atmega clones / alternatives?  - Page 1
Forum section: electronics / general

author: Fflint
author_rank: Frequent Contributor
timestamp: December 29, 2022, 12:55:13 am
content: I'm looking for information if there are any clones of atmega644/Atmega1284 etc that are actually available (like gd32 for stm32) or perhaps alternatives? I need 44 (or more pins) 8mhz clock, 64kb eeprom, 1~2kb ram. I can /, *seem to find anything like it.

author: neil555
author_rank: Contributor
timestamp: December 29, 2022, 02:04:38 am
content: I don't think there are any clones, as for alternatives, whats your use case and how many do you need?Mouser have 387 ATMEGA1284RFR2-ZU's in stock if that helps.https://www.mouser.co.uk/ProductDetail/Microchip-Technology/ATMEGA1284RFR2-ZU?qs=hq%2FeQWvt0cplE0%252B3WWjaTQ%3D%3D

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 29, 2022, 05:55:41 am
content: Sort of, but you'll probably have to go digging for them:http://www.lgtic.com/lgt8fx8p/Offhand, there seems to be a fair number of boards (e.g. basic breakout / "nano") using them, and I guess some hits on Aliexpress etc. for e.g. lgt8f328p. So I mean, if you want to give it a try...Last I looked, AVR-DA were modestly in stock, maybe it's worth adapting the project to that. Or XMEGA. Granted, probably all the stocks are different from when I last looked -- the next best lesson would be to be flexible in your options. Granted, there's a fair difference between classic MEGA, X and Dx: it wouldn't exactly be a trivial porting process. Similar in many respects, but NOT compatible.More applicable, the (MEGA) -4 series is just stripped-down -8 and such, innit? If a 644 will work, a 648 will surely work (with minor porting). I suppose not 328, but maybe some optimizing and compression can be done to conserve space, if it's only marginally over 32k. Between those, and footprint options, you should have a couple dozen parts to choose from, some of which are likely in stock.Tim

author: Fflint
author_rank: Frequent Contributor
timestamp: December 29, 2022, 09:48:21 am
content: Quote from: neil555 on December 29, 2022, 02:04:38 amThanks, I haven't seen this one. It actually does meet my requirements (as mentioned before, 44 pin at least, 10mhz, 64k Rom, 1~2k ram) ideally avr code could run on it.The reason I ask for clones/alternatives is that although the model you mentioned is available on mouser today it might be gone tomorrow while certain clones (like stm32 clones gd32) are persistently available at low prices.So that's what I'm looking for. To port one or two atmega644 designs (that just pretend to be basic logic - the most specific requirement is the pin count and the clock).Quote from: T3sl4co1l on December 29, 2022, 05:55:41 amI have heard about lgt8f328p, but the amount of flash isn't sufficient at only 32k. Something like that would be great if it had 64k (128k even better).Regarding other microchip products, their availability is so hit and miss I would much prefer to avoid them altogether. This is not a commercial project (you could call it a hobby project), but once I port the software to the new chip there is potential for maybe 10 units per month to be required for years(attractively priced) . As it is not commercial I can't buy few hundred at start. I'm looking for something that is likely to be available.Additionally I think once current stocks run out we're not going back to the previous availability of various microcontrollers.The only way we're going to see cheap microcontrollers is the way RPi Rp2040 was done. New design made in a modern process.This is why I mentioned gd32. It is a great example. It is different enough to not be a drop in replacement (ij timing critical stuff at least) so it seems to be continually available cheaper than stm32.

author: bidrohini
author_rank: Regular Contributor
timestamp: December 29, 2022, 01:58:00 pm
content: Never heard of any clones of Atmega

author: Lindley
author_rank: Regular Contributor
timestamp: December 29, 2022, 03:10:59 pm
content: Quote from: Fflint on December 29, 2022, 09:48:21 amIn these times of chip shortages who knows when production /supply will be terminated ?As you expect your project to continue for some years perhaps now is the time to convert your code to something like the RP2040 as even if it is superceeded, the program code will likely work with such a popular package.At just $1 for the RP2040 chip or $4 for the Pico module in one offs the price seems right.https://thepihut.com/products/raspberry-pi-rp2040-microcontrolleThough there are some differences like only 30 i/o to your 32 i/o there are often simple workarounds if you give the idea some thought. Plenty of forum help to overome any such problems.

author: SiliconWizard
author_rank: Super Contributor
timestamp: December 29, 2022, 07:04:39 pm
content: Quote from: bidrohini on December 29, 2022, 01:58:00 pmWhich is interesting, considering how popular they have been and how so many chips have been cloned.They don't seem too hard to implement either.

author: thm_w
author_rank: Super Contributor
timestamp: December 29, 2022, 09:39:52 pm
content: You couldn't read a few threads down?https://www.eevblog.com/forum/microcontrollers/lgt8f328p-clone-of-atmega328-with-lots-of-extras-anybody-use-them/https://www.eevblog.com/forum/microcontrollers/chinese-atmega88-clone/

author: westfw
author_rank: Super Contributor
timestamp: December 30, 2022, 02:27:12 am
content: QuoteYou realize that the ATmega1284 is essentially a 40-pin chip, right? The SMT parts have two extra sets of power pins...There are the LGT parts, which supposedly includes a 48pin version.https://www.aliexpress.us/item/3256804680821882.htmlI have not heard as much about them as the 32pin "Arduino Nano sized" chips. They are "improved" and not exact clones.And there are rumors of ATmega chips that fail to meet low-power specs of "real" ATmegas; I don't know if anyone ever decided whether they were "clones" or just "out of spec" gray-market chips. They seem to show up most often in the Arduino-sized chips - perhaps the sellers think that hobbyist users are less likely to noticed discrepancies...

author: bidrohini
author_rank: Regular Contributor
timestamp: December 30, 2022, 03:44:02 pm
content: Hi, I think you can take a look at this thread regarding LGT8F328phttps://www.eevblog.com/forum/microcontrollers/lgt8f328p-clone-of-atmega328-with-lots-of-extras-anybody-use-them/